From 58055c822fd487063d4cfc80b87a7d9ff12cbcf8 Mon Sep 17 00:00:00 2001
From: Brian Ng <bng412@gmail.com>
Date: Fri, 7 Apr 2017 14:24:42 -0500
Subject: [PATCH 1/2] Support target versions as strings (#231)

---
 README.md                                     |    4 +-
 data/built-ins.json                           | 1362 +++++++++--------
 data/plugins.json                             |  367 ++---
 package.json                                  |    3 +-
 scripts/build-data.js                         |   12 +-
 src/index.js                                  |  109 +-
 src/targets-parser.js                         |  133 ++
 src/utils.js                                  |   67 +
 test/debug-fixtures/android/stdout.txt        |  218 +--
 .../debug-fixtures/builtins-uglify/stdout.txt |   14 +-
 test/debug-fixtures/builtins/stdout.txt       |  222 +--
 test/debug-fixtures/electron/stdout.txt       |  122 +-
 test/debug-fixtures/plugins-only/options.json |    3 +-
 test/debug-fixtures/plugins-only/stdout.txt   |   21 +-
 .../specific-targets/stdout.txt               |  228 +--
 .../versions-decimals/options.json            |   13 +
 .../versions-decimals/stdout.txt              |   45 +
 .../versions-strings/options.json             |   12 +
 .../versions-strings/stdout.txt               |   36 +
 .../preset-options/electron/options.json      |    2 +-
 .../preset-options/no-transform/options.json  |    2 +-
 .../use-builtins-node-web/options.json        |    4 +-
 .../use-builtins-node/options.json            |    2 +-
 .../use-builtins-require/options.json         |    2 +-
 test/index.spec.js                            |  160 +-
 test/targets-parser.spec.js                   |  117 ++
 test/utils.spec.js                            |   61 +
 yarn.lock                                     |   58 +-
 28 files changed, 1864 insertions(+), 1535 deletions(-)
 create mode 100644 src/targets-parser.js
 create mode 100644 src/utils.js
 create mode 100644 test/debug-fixtures/versions-decimals/options.json
 create mode 100644 test/debug-fixtures/versions-decimals/stdout.txt
 create mode 100644 test/debug-fixtures/versions-strings/options.json
 create mode 100644 test/debug-fixtures/versions-strings/stdout.txt
 create mode 100644 test/targets-parser.spec.js
 create mode 100644 test/utils.spec.js

diff --git a/README.md b/README.md
index b3d9e01f..c3e8bc7b 100644
--- a/README.md
+++ b/README.md
@@ -98,11 +98,11 @@ For more information on setting options for a preset, refer to the [plugin/prese
 
 ### `targets`
 
-`{ [string]: number }`, defaults to `{}`.
+`{ [string]: number | string }`, defaults to `{}`.
 
 Takes an object of environment versions to support.
 
-Each target environment takes a number (you can also specify a minor versions like `node: 6.5`)
+Each target environment takes a number or a string (we recommend using a string when specifying minor versions like `node: "6.10"`).
 
 Example environments: `chrome`, `opera`, `edge`, `firefox`, `safari`, `ie`, `ios`, `android`, `node`, `electron`.
 
diff --git a/data/built-ins.json b/data/built-ins.json
index de589f66..dd478aab 100644
--- a/data/built-ins.json
+++ b/data/built-ins.json
@@ -1,848 +1,850 @@
 {
   "es6.typed.array-buffer": {
-    "chrome": 51,
-    "edge": 13,
-    "firefox": 48,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "edge": "13",
+    "firefox": "48",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "es6.typed.data-view": {
-    "chrome": 5,
-    "opera": 12,
-    "edge": 12,
-    "firefox": 15,
-    "safari": 5.1,
-    "node": 0.12,
-    "ie": 10,
-    "android": 4,
-    "ios": 6,
-    "electron": 0.2
+    "chrome": "5",
+    "opera": "12",
+    "edge": "12",
+    "firefox": "15",
+    "safari": "5.1",
+    "node": "0.12",
+    "ie": "10",
+    "android": "4",
+    "ios": "6",
+    "electron": "1.1"
   },
   "es6.typed.int8-array": {
-    "chrome": 51,
-    "edge": 13,
-    "firefox": 48,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "edge": "13",
+    "firefox": "48",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "es6.typed.uint8-array": {
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-    "firefox": 48,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "edge": "13",
+    "firefox": "48",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "es6.typed.uint8-clamped-array": {
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-    "firefox": 48,
-    "safari": 10,
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-    "ios": 10,
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+    "chrome": "51",
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+    "firefox": "48",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
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   },
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-    "firefox": 48,
-    "safari": 10,
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-    "ios": 10,
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+    "chrome": "51",
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+    "firefox": "48",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
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   },
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-    "ios": 10,
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+    "chrome": "51",
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+    "firefox": "48",
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   },
   "es6.map": {
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+    "opera": "41",
+    "electron": "1.5"
   },
   "es7.string.pad-start": {
-    "chrome": 57,
-    "edge": 15,
-    "firefox": 48,
-    "safari": 10,
-    "ios": 10,
-    "opera": 44
+    "chrome": "57",
+    "edge": "15",
+    "firefox": "48",
+    "safari": "10",
+    "ios": "10",
+    "opera": "44",
+    "electron": "1.7"
   },
   "es7.string.pad-end": {
-    "chrome": 57,
-    "edge": 15,
-    "firefox": 48,
-    "safari": 10,
-    "ios": 10,
-    "opera": 44
+    "chrome": "57",
+    "edge": "15",
+    "firefox": "48",
+    "safari": "10",
+    "ios": "10",
+    "opera": "44",
+    "electron": "1.7"
   }
 }
diff --git a/data/plugins.json b/data/plugins.json
index ef9456b9..bca57cae 100644
--- a/data/plugins.json
+++ b/data/plugins.json
@@ -1,231 +1,232 @@
 {
   "check-es2015-constants": {
-    "chrome": 49,
-    "edge": 14,
-    "firefox": 51,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 36,
-    "electron": 1
+    "chrome": "49",
+    "edge": "14",
+    "firefox": "51",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "36",
+    "electron": "1"
   },
   "transform-es2015-arrow-functions": {
-    "chrome": 47,
-    "edge": 13,
-    "firefox": 45,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 34,
-    "electron": 0.36
+    "chrome": "47",
+    "edge": "13",
+    "firefox": "45",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "34",
+    "electron": "0.36"
   },
   "transform-es2015-block-scoped-functions": {
-    "chrome": 41,
-    "edge": 12,
-    "firefox": 46,
-    "safari": 10,
-    "node": 4,
-    "ie": 11,
-    "ios": 10,
-    "opera": 28,
-    "electron": 0.24
+    "chrome": "41",
+    "edge": "12",
+    "firefox": "46",
+    "safari": "10",
+    "node": "4",
+    "ie": "11",
+    "ios": "10",
+    "opera": "28",
+    "electron": "0.24"
   },
   "transform-es2015-block-scoping": {
-    "chrome": 49,
-    "edge": 14,
-    "firefox": 51,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 36,
-    "electron": 1
+    "chrome": "49",
+    "edge": "14",
+    "firefox": "51",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "36",
+    "electron": "1"
   },
   "transform-es2015-classes": {
-    "chrome": 46,
-    "edge": 13,
-    "firefox": 45,
-    "safari": 10,
-    "node": 5,
-    "ios": 10,
-    "opera": 33,
-    "electron": 0.36
+    "chrome": "46",
+    "edge": "13",
+    "firefox": "45",
+    "safari": "10",
+    "node": "5",
+    "ios": "10",
+    "opera": "33",
+    "electron": "0.36"
   },
   "transform-es2015-computed-properties": {
-    "chrome": 44,
-    "edge": 12,
-    "firefox": 34,
-    "safari": 7.1,
-    "node": 4,
-    "ios": 8,
-    "opera": 31,
-    "electron": 0.31
+    "chrome": "44",
+    "edge": "12",
+    "firefox": "34",
+    "safari": "7.1",
+    "node": "4",
+    "ios": "8",
+    "opera": "31",
+    "electron": "0.31"
   },
   "transform-es2015-destructuring": {
-    "chrome": 51,
-    "edge": 15,
-    "firefox": 53,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "edge": "15",
+    "firefox": "53",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "transform-es2015-duplicate-keys": {
-    "chrome": 42,
-    "edge": 12,
-    "firefox": 34,
-    "safari": 9,
-    "node": 4,
-    "ios": 9,
-    "opera": 29,
-    "electron": 0.27
+    "chrome": "42",
+    "edge": "12",
+    "firefox": "34",
+    "safari": "9",
+    "node": "4",
+    "ios": "9",
+    "opera": "29",
+    "electron": "0.27"
   },
   "transform-es2015-for-of": {
-    "chrome": 51,
-    "edge": 15,
-    "firefox": 53,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "edge": "15",
+    "firefox": "53",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "transform-es2015-function-name": {
-    "chrome": 51,
-    "firefox": 53,
-    "safari": 10,
-    "node": 6.5,
-    "ios": 10,
-    "opera": 38,
-    "electron": 1.2
+    "chrome": "51",
+    "firefox": "53",
+    "safari": "10",
+    "node": "6.5",
+    "ios": "10",
+    "opera": "38",
+    "electron": "1.2"
   },
   "transform-es2015-literals": {
-    "chrome": 44,
-    "edge": 12,
-    "firefox": 53,
-    "safari": 9,
-    "node": 4,
-    "ios": 9,
-    "opera": 31,
-    "electron": 0.31
+    "chrome": "44",
+    "edge": "12",
+    "firefox": "53",
+    "safari": "9",
+    "node": "4",
+    "ios": "9",
+    "opera": "31",
+    "electron": "0.31"
   },
   "transform-es2015-object-super": {
-    "chrome": 46,
-    "edge": 13,
-    "firefox": 45,
-    "safari": 10,
-    "node": 5,
-    "ios": 10,
-    "opera": 33,
-    "electron": 0.36
+    "chrome": "46",
+    "edge": "13",
+    "firefox": "45",
+    "safari": "10",
+    "node": "5",
+    "ios": "10",
+    "opera": "33",
+    "electron": "0.36"
   },
   "transform-es2015-parameters": {
-    "chrome": 49,
-    "edge": 14,
-    "firefox": 53,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 36,
-    "electron": 1
+    "chrome": "49",
+    "edge": "14",
+    "firefox": "53",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "36",
+    "electron": "1"
   },
   "transform-es2015-shorthand-properties": {
-    "chrome": 43,
-    "edge": 12,
-    "firefox": 33,
-    "safari": 9,
-    "node": 4,
-    "ios": 9,
-    "opera": 30,
-    "electron": 0.29
+    "chrome": "43",
+    "edge": "12",
+    "firefox": "33",
+    "safari": "9",
+    "node": "4",
+    "ios": "9",
+    "opera": "30",
+    "electron": "0.29"
   },
   "transform-es2015-spread": {
-    "chrome": 46,
-    "edge": 13,
-    "firefox": 36,
-    "safari": 10,
-    "node": 5,
-    "ios": 10,
-    "opera": 33,
-    "electron": 0.36
+    "chrome": "46",
+    "edge": "13",
+    "firefox": "36",
+    "safari": "10",
+    "node": "5",
+    "ios": "10",
+    "opera": "33",
+    "electron": "0.36"
   },
   "transform-es2015-sticky-regex": {
-    "chrome": 49,
-    "edge": 13,
-    "firefox": 3,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 36,
-    "electron": 1
+    "chrome": "49",
+    "edge": "13",
+    "firefox": "3",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "36",
+    "electron": "1"
   },
   "transform-es2015-template-literals": {
-    "chrome": 41,
-    "edge": 13,
-    "firefox": 34,
-    "safari": 9,
-    "node": 4,
-    "ios": 9,
-    "opera": 28,
-    "electron": 0.24
+    "chrome": "41",
+    "edge": "13",
+    "firefox": "34",
+    "safari": "9",
+    "node": "4",
+    "ios": "9",
+    "opera": "28",
+    "electron": "0.24"
   },
   "transform-es2015-typeof-symbol": {
-    "chrome": 38,
-    "edge": 12,
-    "firefox": 36,
-    "safari": 9,
-    "node": 0.12,
-    "android": 5.1,
-    "ios": 9,
-    "opera": 25,
-    "electron": 0.2
+    "chrome": "38",
+    "edge": "12",
+    "firefox": "36",
+    "safari": "9",
+    "node": "0.12",
+    "android": "5.1",
+    "ios": "9",
+    "opera": "25",
+    "electron": "0.2"
   },
   "transform-es2015-unicode-regex": {
-    "chrome": 50,
-    "edge": 13,
-    "firefox": 46,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 37,
-    "electron": 1.1
+    "chrome": "50",
+    "edge": "13",
+    "firefox": "46",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "37",
+    "electron": "1.1"
   },
   "transform-regenerator": {
-    "chrome": 50,
-    "edge": 13,
-    "firefox": 53,
-    "safari": 10,
-    "node": 6,
-    "ios": 10,
-    "opera": 37,
-    "electron": 1.1
+    "chrome": "50",
+    "edge": "13",
+    "firefox": "53",
+    "safari": "10",
+    "node": "6",
+    "ios": "10",
+    "opera": "37",
+    "electron": "1.1"
   },
   "transform-exponentiation-operator": {
-    "chrome": 52,
-    "edge": 14,
-    "firefox": 52,
-    "safari": 10.1,
-    "node": 7,
-    "ios": 10.3,
-    "opera": 39,
-    "electron": 1.3
+    "chrome": "52",
+    "edge": "14",
+    "firefox": "52",
+    "safari": "10.1",
+    "node": "7",
+    "ios": "10.3",
+    "opera": "39",
+    "electron": "1.3"
   },
   "transform-async-to-generator": {
-    "chrome": 55,
-    "edge": 15,
-    "firefox": 52,
-    "safari": 10.1,
-    "node": 7.6,
-    "ios": 10.3,
-    "opera": 42,
-    "electron": 1.6
+    "chrome": "55",
+    "edge": "15",
+    "firefox": "52",
+    "safari": "10.1",
+    "node": "7.6",
+    "ios": "10.3",
+    "opera": "42",
+    "electron": "1.6"
   },
   "syntax-trailing-function-commas": {
-    "chrome": 58,
-    "edge": 14,
-    "firefox": 52,
-    "safari": 10,
-    "ios": 10,
-    "opera": 45
+    "chrome": "58",
+    "edge": "14",
+    "firefox": "52",
+    "safari": "10",
+    "ios": "10",
+    "opera": "45",
+    "electron": "1.7"
   }
 }
diff --git a/package.json b/package.json
index 72dc6611..9821e5f6 100644
--- a/package.json
+++ b/package.json
@@ -50,7 +50,8 @@
     "babel-plugin-transform-exponentiation-operator": "^6.22.0",
     "babel-plugin-transform-regenerator": "^6.22.0",
     "browserslist": "^2.1.2",
-    "invariant": "^2.2.2"
+    "invariant": "^2.2.2",
+    "semver": "^5.3.0"
   },
   "devDependencies": {
     "babel-cli": "^6.23.0",
diff --git a/scripts/build-data.js b/scripts/build-data.js
index 94ce128d..4f4be72c 100644
--- a/scripts/build-data.js
+++ b/scripts/build-data.js
@@ -211,20 +211,22 @@ const generateData = (environments, features) => {
     environments.forEach((env) => {
       const version = getLowestImplementedVersion(options, env);
       if (version !== null) {
-        plugin[env] = version;
+        plugin[env] = version.toString();
       }
     });
 
-    // add opera
     if (plugin.chrome) {
+      // add opera
       if (plugin.chrome >= 28) {
-        plugin.opera = plugin.chrome - 13;
+        plugin.opera = (plugin.chrome - 13).toString();
       } else if (plugin.chrome === 5) {
-        plugin.opera = 12;
+        plugin.opera = "12";
       }
+
+      // add electron
       const electronVersion = chromiumToElectron(plugin.chrome);
       if (electronVersion) {
-        plugin.electron = electronVersion;
+        plugin.electron = electronVersion.toString();
       }
     }
 
diff --git a/src/index.js b/src/index.js
index fe68ea23..b827a766 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,24 +1,25 @@
-import browserslist from "browserslist";
+import semver from "semver";
 import builtInsList from "../data/built-ins.json";
 import { defaultWebIncludes } from "./default-includes";
 import moduleTransformations from "./module-transformations";
 import normalizeOptions from "./normalize-options.js";
 import pluginList from "../data/plugins.json";
 import transformPolyfillRequirePlugin from "./transform-polyfill-require-plugin";
+import getTargets from "./targets-parser";
+import { _extends, prettifyTargets, prettifyVersion, semverify } from "./utils";
 
 /**
  * Determine if a transformation is required
+ *
+ * NOTE: This assumes `supportedEnvironments` has already been parsed by `getTargets`
+ *
  * @param  {Object}  supportedEnvironments  An Object containing environment keys and the lowest
  *                                          supported version as a value
  * @param  {Object}  plugin                 An Object containing environment keys and the lowest
  *                                          version the feature was implemented in as a value
- * @return {Boolean}  Whether or not the transformation is required
+ * @return {Boolean} Whether or not the transformation is required
  */
 export const isPluginRequired = (supportedEnvironments, plugin) => {
-  if (supportedEnvironments.browsers) {
-    supportedEnvironments = getTargets(supportedEnvironments);
-  }
-
   const targetEnvironments = Object.keys(supportedEnvironments);
 
   if (targetEnvironments.length === 0) { return true; }
@@ -31,90 +32,20 @@ export const isPluginRequired = (supportedEnvironments, plugin) => {
       const lowestImplementedVersion = plugin[environment];
       const lowestTargetedVersion = supportedEnvironments[environment];
 
-      if (typeof lowestTargetedVersion === "string") {
-        throw new Error(`Target version must be a number,
-          '${lowestTargetedVersion}' was given for '${environment}'`);
+      if (!semver.valid(lowestTargetedVersion)) {
+        throw new Error(
+          // eslint-disable-next-line max-len
+          `Invalid version passed for target "${environment}": "${lowestTargetedVersion}". Versions must be in semver format (major.minor.patch)`,
+        );
       }
 
-      return lowestTargetedVersion < lowestImplementedVersion;
+      return semver.gt(
+        semverify(lowestImplementedVersion),
+        lowestTargetedVersion,
+      );
     });
 
-  return isRequiredForEnvironments.length > 0 ? true : false;
-};
-
-const isBrowsersQueryValid = (browsers) => {
-  return typeof browsers === "string" || Array.isArray(browsers);
-};
-
-const browserNameMap = {
-  android: "android",
-  chrome: "chrome",
-  edge: "edge",
-  firefox: "firefox",
-  ie: "ie",
-  ios_saf: "ios",
-  safari: "safari"
-};
-
-const getLowestVersions = (browsers) => {
-  return browsers.reduce((all, browser) => {
-    const [browserName, browserVersion] = browser.split(" ");
-    const normalizedBrowserName = browserNameMap[browserName];
-    const parsedBrowserVersion = parseInt(browserVersion);
-    if (normalizedBrowserName && !isNaN(parsedBrowserVersion)) {
-      all[normalizedBrowserName] = Math.min(all[normalizedBrowserName] || Infinity, parsedBrowserVersion);
-    }
-    return all;
-  }, {});
-};
-
-const mergeBrowsers = (fromQuery, fromTarget) => {
-  return Object.keys(fromTarget).reduce((queryObj, targKey) => {
-    if (targKey !== "browsers") {
-      queryObj[targKey] = fromTarget[targKey];
-    }
-    return queryObj;
-  }, fromQuery);
-};
-
-export const getCurrentNodeVersion = () => {
-  return parseFloat(process.versions.node);
-};
-
-const _extends = Object.assign || function (target) {
-  for (let i = 1; i < arguments.length; i++) {
-    const source = arguments[i];
-    for (const key in source) {
-      if (Object.prototype.hasOwnProperty.call(source, key)) {
-        target[key] = source[key];
-      }
-    }
-  }
-  return target;
-};
-
-
-export const getTargets = (targets = {}) => {
-  const targetOpts = _extends({}, targets);
-
-  if (targetOpts.node === true || targetOpts.node === "current") {
-    targetOpts.node = getCurrentNodeVersion();
-  }
-
-  if (typeof targetOpts.electron === "string") {
-    targetOpts.electron = parseFloat(targetOpts.electron);
-  }
-
-  if (targetOpts.hasOwnProperty("uglify") && !targetOpts.uglify) {
-    delete targetOpts.uglify;
-  }
-
-  const browserOpts = targetOpts.browsers;
-  if (isBrowsersQueryValid(browserOpts)) {
-    const queryBrowsers = getLowestVersions(browserslist(browserOpts));
-    return mergeBrowsers(queryBrowsers, targetOpts);
-  }
-  return targetOpts;
+  return isRequiredForEnvironments.length > 0;
 };
 
 let hasBeenLogged = false;
@@ -123,8 +54,8 @@ const logPlugin = (plugin, targets, list) => {
   const envList = list[plugin] || {};
   const filteredList = Object.keys(targets)
   .reduce((a, b) => {
-    if (!envList[b] || targets[b] < envList[b]) {
-      a[b] = targets[b];
+    if (!envList[b] || semver.lt(targets[b], semverify(envList[b]))) {
+      a[b] = prettifyVersion(targets[b]);
     }
     return a;
   }, {});
@@ -191,7 +122,7 @@ export default function buildPreset(context, opts = {}) {
     hasBeenLogged = true;
     console.log("babel-preset-env: `DEBUG` option");
     console.log("\nUsing targets:");
-    console.log(JSON.stringify(targets, null, 2));
+    console.log(JSON.stringify(prettifyTargets(targets), null, 2));
     console.log(`\nModules transform: ${moduleType}`);
     console.log("\nUsing plugins:");
     transformations.forEach((transform) => {
diff --git a/src/targets-parser.js b/src/targets-parser.js
new file mode 100644
index 00000000..3a1096a1
--- /dev/null
+++ b/src/targets-parser.js
@@ -0,0 +1,133 @@
+import browserslist from "browserslist";
+import semver from "semver";
+import { semverify } from "./utils";
+
+const browserNameMap = {
+  android: "android",
+  chrome: "chrome",
+  edge: "edge",
+  firefox: "firefox",
+  ie: "ie",
+  ios_saf: "ios",
+  safari: "safari",
+};
+
+const isBrowsersQueryValid = (browsers) =>
+  typeof browsers === "string" || Array.isArray(browsers);
+
+const semverMin = (first, second) => {
+  return first && semver.lt(first, second) ? first : second;
+};
+
+const getLowestVersions = (browsers) => {
+  return browsers.reduce(
+    (all, browser) => {
+      const [browserName, browserVersion] = browser.split(" ");
+      const normalizedBrowserName = browserNameMap[browserName];
+
+      if (!normalizedBrowserName) {
+        return all;
+      }
+
+      try {
+        // Browser version can return as "10.0-10.2"
+        const splitVersion = browserVersion.split("-")[0];
+        const parsedBrowserVersion = semverify(splitVersion);
+
+        all[normalizedBrowserName] = semverMin(
+          all[normalizedBrowserName],
+          parsedBrowserVersion,
+        );
+      } catch (e) {}
+
+      return all;
+    },
+    {},
+  );
+};
+
+const outputDecimalWarning = (decimalTargets) => {
+  if (!decimalTargets || !decimalTargets.length) {
+    return;
+  }
+
+  console.log("Warning, the following targets are using a decimal version:");
+  console.log("");
+  decimalTargets.forEach(({ target, value }) =>
+    console.log(`  ${target}: ${value}`));
+  console.log("");
+  console.log(
+    "We recommend using a string for minor/patch versions to avoid numbers like 6.10",
+  );
+  console.log("getting parsed as 6.1, which can lead to unexpected behavior.");
+  console.log("");
+};
+
+const targetParserMap = {
+  __default: (target, value) => [target, semverify(value)],
+
+  // Parse `node: true` and `node: "current"` to version
+  node: (target, value) => {
+    const parsed = value === true || value === "current"
+      ? process.versions.node
+      : semverify(value);
+
+    return [target, parsed];
+  },
+
+  // Only valid value for Uglify is `true`
+  uglify: (target, value) => [target, value === true],
+};
+
+const getTargets = (targets = {}) => {
+  let targetOpts = {};
+
+  // Parse browsers target via browserslist
+  if (isBrowsersQueryValid(targets.browsers)) {
+    targetOpts = getLowestVersions(browserslist(targets.browsers));
+  }
+
+  // Parse remaining targets
+  const parsed = Object.keys(targets).reduce(
+    (results, target) => {
+      if (target !== "browsers") {
+        const value = targets[target];
+
+        // Warn when specifying minor/patch as a decimal
+        if (typeof value === "number" && value % 1 !== 0) {
+          results.decimalWarnings.push({ target, value });
+        }
+
+        // Check if we have a target parser?
+        const parser = targetParserMap[target] || targetParserMap.__default;
+        const [parsedTarget, parsedValue] = parser(target, value);
+
+        if (parsedValue) {
+          // Merge (lowest wins)
+          if (typeof parsedValue === "string") {
+            results.targets[parsedTarget] = semverMin(
+              results.targets[parsedTarget],
+              parsedValue,
+            );
+          } else {
+            // We can remove this block if/when we replace Uglify target
+            // with top level option
+            results.targets[parsedTarget] = parsedValue;
+          }
+        }
+      }
+
+      return results;
+    },
+    {
+      targets: targetOpts,
+      decimalWarnings: [],
+    },
+  );
+
+  outputDecimalWarning(parsed.decimalWarnings);
+
+  return parsed.targets;
+};
+
+export default getTargets;
diff --git a/src/utils.js b/src/utils.js
new file mode 100644
index 00000000..561d74f2
--- /dev/null
+++ b/src/utils.js
@@ -0,0 +1,67 @@
+// @flow
+import semver from "semver";
+
+export const _extends = Object.assign ||
+  function(target) {
+    for (let i = 1; i < arguments.length; i++) {
+      const source = arguments[i];
+      for (const key in source) {
+        if (Object.prototype.hasOwnProperty.call(source, key)) {
+          target[key] = source[key];
+        }
+      }
+    }
+    return target;
+  };
+
+// Convert version to a semver value.
+// 2.5 -> 2.5.0; 1 -> 1.0.0;
+export const semverify = (version) => {
+  if (typeof version === "string" && semver.valid(version)) {
+    return version;
+  }
+
+  const split = version.toString().split(".");
+
+  while (split.length < 3) {
+    split.push(0);
+  }
+
+  return split.join(".");
+};
+
+export const prettifyVersion = (version) => {
+  if (typeof version !== "string") {
+    return version;
+  }
+
+  const parts = [semver.major(version)];
+  const minor = semver.minor(version);
+  const patch = semver.patch(version);
+
+  if (minor || patch) {
+    parts.push(minor);
+  }
+
+  if (patch) {
+    parts.push(patch);
+  }
+
+  return parts.join(".");
+};
+
+export const prettifyTargets = (targets = {}) => {
+  return Object.keys(targets).reduce(
+    (results, target) => {
+      let value = targets[target];
+
+      if (typeof value === "string") {
+        value = prettifyVersion(value);
+      }
+
+      results[target] = value;
+      return results;
+    },
+    {},
+  );
+};
diff --git a/test/debug-fixtures/android/stdout.txt b/test/debug-fixtures/android/stdout.txt
index 3e792956..4c41227a 100644
--- a/test/debug-fixtures/android/stdout.txt
+++ b/test/debug-fixtures/android/stdout.txt
@@ -2,120 +2,120 @@ babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "android": 4
+  "android": "4"
 }
 
 Modules transform: commonjs
 
 Using plugins:
-  check-es2015-constants {"android":4}
-  transform-es2015-arrow-functions {"android":4}
-  transform-es2015-block-scoped-functions {"android":4}
-  transform-es2015-block-scoping {"android":4}
-  transform-es2015-classes {"android":4}
-  transform-es2015-computed-properties {"android":4}
-  transform-es2015-destructuring {"android":4}
-  transform-es2015-duplicate-keys {"android":4}
-  transform-es2015-for-of {"android":4}
-  transform-es2015-function-name {"android":4}
-  transform-es2015-literals {"android":4}
-  transform-es2015-object-super {"android":4}
-  transform-es2015-parameters {"android":4}
-  transform-es2015-shorthand-properties {"android":4}
-  transform-es2015-spread {"android":4}
-  transform-es2015-sticky-regex {"android":4}
-  transform-es2015-template-literals {"android":4}
-  transform-es2015-typeof-symbol {"android":4}
-  transform-es2015-unicode-regex {"android":4}
-  transform-regenerator {"android":4}
-  transform-exponentiation-operator {"android":4}
-  transform-async-to-generator {"android":4}
-  syntax-trailing-function-commas {"android":4}
+  check-es2015-constants {"android":"4"}
+  transform-es2015-arrow-functions {"android":"4"}
+  transform-es2015-block-scoped-functions {"android":"4"}
+  transform-es2015-block-scoping {"android":"4"}
+  transform-es2015-classes {"android":"4"}
+  transform-es2015-computed-properties {"android":"4"}
+  transform-es2015-destructuring {"android":"4"}
+  transform-es2015-duplicate-keys {"android":"4"}
+  transform-es2015-for-of {"android":"4"}
+  transform-es2015-function-name {"android":"4"}
+  transform-es2015-literals {"android":"4"}
+  transform-es2015-object-super {"android":"4"}
+  transform-es2015-parameters {"android":"4"}
+  transform-es2015-shorthand-properties {"android":"4"}
+  transform-es2015-spread {"android":"4"}
+  transform-es2015-sticky-regex {"android":"4"}
+  transform-es2015-template-literals {"android":"4"}
+  transform-es2015-typeof-symbol {"android":"4"}
+  transform-es2015-unicode-regex {"android":"4"}
+  transform-regenerator {"android":"4"}
+  transform-exponentiation-operator {"android":"4"}
+  transform-async-to-generator {"android":"4"}
+  syntax-trailing-function-commas {"android":"4"}
 
 Using polyfills:
-  es6.typed.array-buffer {"android":4}
-  es6.typed.int8-array {"android":4}
-  es6.typed.uint8-array {"android":4}
-  es6.typed.uint8-clamped-array {"android":4}
-  es6.typed.int16-array {"android":4}
-  es6.typed.uint16-array {"android":4}
-  es6.typed.int32-array {"android":4}
-  es6.typed.uint32-array {"android":4}
-  es6.typed.float32-array {"android":4}
-  es6.typed.float64-array {"android":4}
-  es6.map {"android":4}
-  es6.set {"android":4}
-  es6.weak-map {"android":4}
-  es6.weak-set {"android":4}
-  es6.reflect.apply {"android":4}
-  es6.reflect.construct {"android":4}
-  es6.reflect.define-property {"android":4}
-  es6.reflect.delete-property {"android":4}
-  es6.reflect.get {"android":4}
-  es6.reflect.get-own-property-descriptor {"android":4}
-  es6.reflect.get-prototype-of {"android":4}
-  es6.reflect.has {"android":4}
-  es6.reflect.is-extensible {"android":4}
-  es6.reflect.own-keys {"android":4}
-  es6.reflect.prevent-extensions {"android":4}
-  es6.reflect.set {"android":4}
-  es6.reflect.set-prototype-of {"android":4}
-  es6.promise {"android":4}
-  es6.symbol {"android":4}
-  es6.object.assign {"android":4}
-  es6.object.is {"android":4}
-  es6.object.set-prototype-of {"android":4}
-  es6.function.name {"android":4}
-  es6.string.raw {"android":4}
-  es6.string.from-code-point {"android":4}
-  es6.string.code-point-at {"android":4}
-  es6.string.repeat {"android":4}
-  es6.string.starts-with {"android":4}
-  es6.string.ends-with {"android":4}
-  es6.string.includes {"android":4}
-  es6.regexp.flags {"android":4}
-  es6.regexp.match {"android":4}
-  es6.regexp.replace {"android":4}
-  es6.regexp.split {"android":4}
-  es6.regexp.search {"android":4}
-  es6.array.from {"android":4}
-  es6.array.of {"android":4}
-  es6.array.copy-within {"android":4}
-  es6.array.find {"android":4}
-  es6.array.find-index {"android":4}
-  es6.array.fill {"android":4}
-  es6.array.iterator {"android":4}
-  es6.number.is-finite {"android":4}
-  es6.number.is-integer {"android":4}
-  es6.number.is-safe-integer {"android":4}
-  es6.number.is-nan {"android":4}
-  es6.number.epsilon {"android":4}
-  es6.number.min-safe-integer {"android":4}
-  es6.number.max-safe-integer {"android":4}
-  es6.math.acosh {"android":4}
-  es6.math.asinh {"android":4}
-  es6.math.atanh {"android":4}
-  es6.math.cbrt {"android":4}
-  es6.math.clz32 {"android":4}
-  es6.math.cosh {"android":4}
-  es6.math.expm1 {"android":4}
-  es6.math.fround {"android":4}
-  es6.math.hypot {"android":4}
-  es6.math.imul {"android":4}
-  es6.math.log1p {"android":4}
-  es6.math.log10 {"android":4}
-  es6.math.log2 {"android":4}
-  es6.math.sign {"android":4}
-  es6.math.sinh {"android":4}
-  es6.math.tanh {"android":4}
-  es6.math.trunc {"android":4}
-  es7.array.includes {"android":4}
-  es7.object.values {"android":4}
-  es7.object.entries {"android":4}
-  es7.object.get-own-property-descriptors {"android":4}
-  es7.string.pad-start {"android":4}
-  es7.string.pad-end {"android":4}
-  web.timers {"android":4}
-  web.immediate {"android":4}
-  web.dom.iterable {"android":4}
+  es6.typed.array-buffer {"android":"4"}
+  es6.typed.int8-array {"android":"4"}
+  es6.typed.uint8-array {"android":"4"}
+  es6.typed.uint8-clamped-array {"android":"4"}
+  es6.typed.int16-array {"android":"4"}
+  es6.typed.uint16-array {"android":"4"}
+  es6.typed.int32-array {"android":"4"}
+  es6.typed.uint32-array {"android":"4"}
+  es6.typed.float32-array {"android":"4"}
+  es6.typed.float64-array {"android":"4"}
+  es6.map {"android":"4"}
+  es6.set {"android":"4"}
+  es6.weak-map {"android":"4"}
+  es6.weak-set {"android":"4"}
+  es6.reflect.apply {"android":"4"}
+  es6.reflect.construct {"android":"4"}
+  es6.reflect.define-property {"android":"4"}
+  es6.reflect.delete-property {"android":"4"}
+  es6.reflect.get {"android":"4"}
+  es6.reflect.get-own-property-descriptor {"android":"4"}
+  es6.reflect.get-prototype-of {"android":"4"}
+  es6.reflect.has {"android":"4"}
+  es6.reflect.is-extensible {"android":"4"}
+  es6.reflect.own-keys {"android":"4"}
+  es6.reflect.prevent-extensions {"android":"4"}
+  es6.reflect.set {"android":"4"}
+  es6.reflect.set-prototype-of {"android":"4"}
+  es6.promise {"android":"4"}
+  es6.symbol {"android":"4"}
+  es6.object.assign {"android":"4"}
+  es6.object.is {"android":"4"}
+  es6.object.set-prototype-of {"android":"4"}
+  es6.function.name {"android":"4"}
+  es6.string.raw {"android":"4"}
+  es6.string.from-code-point {"android":"4"}
+  es6.string.code-point-at {"android":"4"}
+  es6.string.repeat {"android":"4"}
+  es6.string.starts-with {"android":"4"}
+  es6.string.ends-with {"android":"4"}
+  es6.string.includes {"android":"4"}
+  es6.regexp.flags {"android":"4"}
+  es6.regexp.match {"android":"4"}
+  es6.regexp.replace {"android":"4"}
+  es6.regexp.split {"android":"4"}
+  es6.regexp.search {"android":"4"}
+  es6.array.from {"android":"4"}
+  es6.array.of {"android":"4"}
+  es6.array.copy-within {"android":"4"}
+  es6.array.find {"android":"4"}
+  es6.array.find-index {"android":"4"}
+  es6.array.fill {"android":"4"}
+  es6.array.iterator {"android":"4"}
+  es6.number.is-finite {"android":"4"}
+  es6.number.is-integer {"android":"4"}
+  es6.number.is-safe-integer {"android":"4"}
+  es6.number.is-nan {"android":"4"}
+  es6.number.epsilon {"android":"4"}
+  es6.number.min-safe-integer {"android":"4"}
+  es6.number.max-safe-integer {"android":"4"}
+  es6.math.acosh {"android":"4"}
+  es6.math.asinh {"android":"4"}
+  es6.math.atanh {"android":"4"}
+  es6.math.cbrt {"android":"4"}
+  es6.math.clz32 {"android":"4"}
+  es6.math.cosh {"android":"4"}
+  es6.math.expm1 {"android":"4"}
+  es6.math.fround {"android":"4"}
+  es6.math.hypot {"android":"4"}
+  es6.math.imul {"android":"4"}
+  es6.math.log1p {"android":"4"}
+  es6.math.log10 {"android":"4"}
+  es6.math.log2 {"android":"4"}
+  es6.math.sign {"android":"4"}
+  es6.math.sinh {"android":"4"}
+  es6.math.tanh {"android":"4"}
+  es6.math.trunc {"android":"4"}
+  es7.array.includes {"android":"4"}
+  es7.object.values {"android":"4"}
+  es7.object.entries {"android":"4"}
+  es7.object.get-own-property-descriptors {"android":"4"}
+  es7.string.pad-start {"android":"4"}
+  es7.string.pad-end {"android":"4"}
+  web.timers {"android":"4"}
+  web.immediate {"android":"4"}
+  web.dom.iterable {"android":"4"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/builtins-uglify/stdout.txt b/test/debug-fixtures/builtins-uglify/stdout.txt
index 44f3707b..42973232 100644
--- a/test/debug-fixtures/builtins-uglify/stdout.txt
+++ b/test/debug-fixtures/builtins-uglify/stdout.txt
@@ -2,7 +2,7 @@ babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "chrome": 55,
+  "chrome": "55",
   "uglify": true
 }
 
@@ -31,12 +31,12 @@ Using plugins:
   transform-regenerator {"uglify":true}
   transform-exponentiation-operator {"uglify":true}
   transform-async-to-generator {"uglify":true}
-  syntax-trailing-function-commas {"chrome":55,"uglify":true}
+  syntax-trailing-function-commas {"chrome":"55","uglify":true}
 
 Using polyfills:
-  es7.string.pad-start {"chrome":55}
-  es7.string.pad-end {"chrome":55}
-  web.timers {"chrome":55}
-  web.immediate {"chrome":55}
-  web.dom.iterable {"chrome":55}
+  es7.string.pad-start {"chrome":"55"}
+  es7.string.pad-end {"chrome":"55"}
+  web.timers {"chrome":"55"}
+  web.immediate {"chrome":"55"}
+  web.dom.iterable {"chrome":"55"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/builtins/stdout.txt b/test/debug-fixtures/builtins/stdout.txt
index 1779d879..97ffb883 100644
--- a/test/debug-fixtures/builtins/stdout.txt
+++ b/test/debug-fixtures/builtins/stdout.txt
@@ -2,122 +2,122 @@ babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "chrome": 54,
-  "ie": 10,
-  "node": 6
+  "chrome": "54",
+  "ie": "10",
+  "node": "6"
 }
 
 Modules transform: commonjs
 
 Using plugins:
-  check-es2015-constants {"ie":10}
-  transform-es2015-arrow-functions {"ie":10}
-  transform-es2015-block-scoped-functions {"ie":10}
-  transform-es2015-block-scoping {"ie":10}
-  transform-es2015-classes {"ie":10}
-  transform-es2015-computed-properties {"ie":10}
-  transform-es2015-destructuring {"ie":10,"node":6}
-  transform-es2015-duplicate-keys {"ie":10}
-  transform-es2015-for-of {"ie":10,"node":6}
-  transform-es2015-function-name {"ie":10,"node":6}
-  transform-es2015-literals {"ie":10}
-  transform-es2015-object-super {"ie":10}
-  transform-es2015-parameters {"ie":10}
-  transform-es2015-shorthand-properties {"ie":10}
-  transform-es2015-spread {"ie":10}
-  transform-es2015-sticky-regex {"ie":10}
-  transform-es2015-template-literals {"ie":10}
-  transform-es2015-typeof-symbol {"ie":10}
-  transform-es2015-unicode-regex {"ie":10}
-  transform-regenerator {"ie":10}
-  transform-exponentiation-operator {"ie":10,"node":6}
-  transform-async-to-generator {"chrome":54,"ie":10,"node":6}
-  syntax-trailing-function-commas {"chrome":54,"ie":10,"node":6}
+  check-es2015-constants {"ie":"10"}
+  transform-es2015-arrow-functions {"ie":"10"}
+  transform-es2015-block-scoped-functions {"ie":"10"}
+  transform-es2015-block-scoping {"ie":"10"}
+  transform-es2015-classes {"ie":"10"}
+  transform-es2015-computed-properties {"ie":"10"}
+  transform-es2015-destructuring {"ie":"10","node":"6"}
+  transform-es2015-duplicate-keys {"ie":"10"}
+  transform-es2015-for-of {"ie":"10","node":"6"}
+  transform-es2015-function-name {"ie":"10","node":"6"}
+  transform-es2015-literals {"ie":"10"}
+  transform-es2015-object-super {"ie":"10"}
+  transform-es2015-parameters {"ie":"10"}
+  transform-es2015-shorthand-properties {"ie":"10"}
+  transform-es2015-spread {"ie":"10"}
+  transform-es2015-sticky-regex {"ie":"10"}
+  transform-es2015-template-literals {"ie":"10"}
+  transform-es2015-typeof-symbol {"ie":"10"}
+  transform-es2015-unicode-regex {"ie":"10"}
+  transform-regenerator {"ie":"10"}
+  transform-exponentiation-operator {"ie":"10","node":"6"}
+  transform-async-to-generator {"chrome":"54","ie":"10","node":"6"}
+  syntax-trailing-function-commas {"chrome":"54","ie":"10","node":"6"}
 
 Using polyfills:
-  es6.typed.array-buffer {"ie":10,"node":6}
-  es6.typed.int8-array {"ie":10,"node":6}
-  es6.typed.uint8-array {"ie":10,"node":6}
-  es6.typed.uint8-clamped-array {"ie":10,"node":6}
-  es6.typed.int16-array {"ie":10,"node":6}
-  es6.typed.uint16-array {"ie":10,"node":6}
-  es6.typed.int32-array {"ie":10,"node":6}
-  es6.typed.uint32-array {"ie":10,"node":6}
-  es6.typed.float32-array {"ie":10,"node":6}
-  es6.typed.float64-array {"ie":10,"node":6}
-  es6.map {"ie":10,"node":6}
-  es6.set {"ie":10,"node":6}
-  es6.weak-map {"ie":10,"node":6}
-  es6.weak-set {"ie":10,"node":6}
-  es6.reflect.apply {"ie":10}
-  es6.reflect.construct {"ie":10}
-  es6.reflect.define-property {"ie":10}
-  es6.reflect.delete-property {"ie":10}
-  es6.reflect.get {"ie":10}
-  es6.reflect.get-own-property-descriptor {"ie":10}
-  es6.reflect.get-prototype-of {"ie":10}
-  es6.reflect.has {"ie":10}
-  es6.reflect.is-extensible {"ie":10}
-  es6.reflect.own-keys {"ie":10}
-  es6.reflect.prevent-extensions {"ie":10}
-  es6.reflect.set {"ie":10}
-  es6.reflect.set-prototype-of {"ie":10}
-  es6.promise {"ie":10,"node":6}
-  es6.symbol {"ie":10,"node":6}
-  es6.object.assign {"ie":10}
-  es6.object.is {"ie":10}
-  es6.object.set-prototype-of {"ie":10}
-  es6.function.name {"ie":10,"node":6}
-  es6.string.raw {"ie":10}
-  es6.string.from-code-point {"ie":10}
-  es6.string.code-point-at {"ie":10}
-  es6.string.repeat {"ie":10}
-  es6.string.starts-with {"ie":10}
-  es6.string.ends-with {"ie":10}
-  es6.string.includes {"ie":10}
-  es6.regexp.flags {"ie":10}
-  es6.regexp.match {"ie":10}
-  es6.regexp.replace {"ie":10}
-  es6.regexp.split {"ie":10}
-  es6.regexp.search {"ie":10}
-  es6.array.from {"ie":10,"node":6}
-  es6.array.of {"ie":10}
-  es6.array.copy-within {"ie":10}
-  es6.array.find {"ie":10}
-  es6.array.find-index {"ie":10}
-  es6.array.fill {"ie":10}
-  es6.array.iterator {"ie":10}
-  es6.number.is-finite {"ie":10}
-  es6.number.is-integer {"ie":10}
-  es6.number.is-safe-integer {"ie":10}
-  es6.number.is-nan {"ie":10}
-  es6.number.epsilon {"ie":10}
-  es6.number.min-safe-integer {"ie":10}
-  es6.number.max-safe-integer {"ie":10}
-  es6.math.acosh {"ie":10}
-  es6.math.asinh {"ie":10}
-  es6.math.atanh {"ie":10}
-  es6.math.cbrt {"ie":10}
-  es6.math.clz32 {"ie":10}
-  es6.math.cosh {"ie":10}
-  es6.math.expm1 {"ie":10}
-  es6.math.fround {"ie":10}
-  es6.math.hypot {"ie":10}
-  es6.math.imul {"ie":10}
-  es6.math.log1p {"ie":10}
-  es6.math.log10 {"ie":10}
-  es6.math.log2 {"ie":10}
-  es6.math.sign {"ie":10}
-  es6.math.sinh {"ie":10}
-  es6.math.tanh {"ie":10}
-  es6.math.trunc {"ie":10}
-  es7.array.includes {"ie":10}
-  es7.object.values {"ie":10,"node":6}
-  es7.object.entries {"ie":10,"node":6}
-  es7.object.get-own-property-descriptors {"ie":10,"node":6}
-  es7.string.pad-start {"chrome":54,"ie":10,"node":6}
-  es7.string.pad-end {"chrome":54,"ie":10,"node":6}
-  web.timers {"chrome":54,"ie":10,"node":6}
-  web.immediate {"chrome":54,"ie":10,"node":6}
-  web.dom.iterable {"chrome":54,"ie":10,"node":6}
+  es6.typed.array-buffer {"ie":"10","node":"6"}
+  es6.typed.int8-array {"ie":"10","node":"6"}
+  es6.typed.uint8-array {"ie":"10","node":"6"}
+  es6.typed.uint8-clamped-array {"ie":"10","node":"6"}
+  es6.typed.int16-array {"ie":"10","node":"6"}
+  es6.typed.uint16-array {"ie":"10","node":"6"}
+  es6.typed.int32-array {"ie":"10","node":"6"}
+  es6.typed.uint32-array {"ie":"10","node":"6"}
+  es6.typed.float32-array {"ie":"10","node":"6"}
+  es6.typed.float64-array {"ie":"10","node":"6"}
+  es6.map {"ie":"10","node":"6"}
+  es6.set {"ie":"10","node":"6"}
+  es6.weak-map {"ie":"10","node":"6"}
+  es6.weak-set {"ie":"10","node":"6"}
+  es6.reflect.apply {"ie":"10"}
+  es6.reflect.construct {"ie":"10"}
+  es6.reflect.define-property {"ie":"10"}
+  es6.reflect.delete-property {"ie":"10"}
+  es6.reflect.get {"ie":"10"}
+  es6.reflect.get-own-property-descriptor {"ie":"10"}
+  es6.reflect.get-prototype-of {"ie":"10"}
+  es6.reflect.has {"ie":"10"}
+  es6.reflect.is-extensible {"ie":"10"}
+  es6.reflect.own-keys {"ie":"10"}
+  es6.reflect.prevent-extensions {"ie":"10"}
+  es6.reflect.set {"ie":"10"}
+  es6.reflect.set-prototype-of {"ie":"10"}
+  es6.promise {"ie":"10","node":"6"}
+  es6.symbol {"ie":"10","node":"6"}
+  es6.object.assign {"ie":"10"}
+  es6.object.is {"ie":"10"}
+  es6.object.set-prototype-of {"ie":"10"}
+  es6.function.name {"ie":"10","node":"6"}
+  es6.string.raw {"ie":"10"}
+  es6.string.from-code-point {"ie":"10"}
+  es6.string.code-point-at {"ie":"10"}
+  es6.string.repeat {"ie":"10"}
+  es6.string.starts-with {"ie":"10"}
+  es6.string.ends-with {"ie":"10"}
+  es6.string.includes {"ie":"10"}
+  es6.regexp.flags {"ie":"10"}
+  es6.regexp.match {"ie":"10"}
+  es6.regexp.replace {"ie":"10"}
+  es6.regexp.split {"ie":"10"}
+  es6.regexp.search {"ie":"10"}
+  es6.array.from {"ie":"10","node":"6"}
+  es6.array.of {"ie":"10"}
+  es6.array.copy-within {"ie":"10"}
+  es6.array.find {"ie":"10"}
+  es6.array.find-index {"ie":"10"}
+  es6.array.fill {"ie":"10"}
+  es6.array.iterator {"ie":"10"}
+  es6.number.is-finite {"ie":"10"}
+  es6.number.is-integer {"ie":"10"}
+  es6.number.is-safe-integer {"ie":"10"}
+  es6.number.is-nan {"ie":"10"}
+  es6.number.epsilon {"ie":"10"}
+  es6.number.min-safe-integer {"ie":"10"}
+  es6.number.max-safe-integer {"ie":"10"}
+  es6.math.acosh {"ie":"10"}
+  es6.math.asinh {"ie":"10"}
+  es6.math.atanh {"ie":"10"}
+  es6.math.cbrt {"ie":"10"}
+  es6.math.clz32 {"ie":"10"}
+  es6.math.cosh {"ie":"10"}
+  es6.math.expm1 {"ie":"10"}
+  es6.math.fround {"ie":"10"}
+  es6.math.hypot {"ie":"10"}
+  es6.math.imul {"ie":"10"}
+  es6.math.log1p {"ie":"10"}
+  es6.math.log10 {"ie":"10"}
+  es6.math.log2 {"ie":"10"}
+  es6.math.sign {"ie":"10"}
+  es6.math.sinh {"ie":"10"}
+  es6.math.tanh {"ie":"10"}
+  es6.math.trunc {"ie":"10"}
+  es7.array.includes {"ie":"10"}
+  es7.object.values {"ie":"10","node":"6"}
+  es7.object.entries {"ie":"10","node":"6"}
+  es7.object.get-own-property-descriptors {"ie":"10","node":"6"}
+  es7.string.pad-start {"chrome":"54","ie":"10","node":"6"}
+  es7.string.pad-end {"chrome":"54","ie":"10","node":"6"}
+  web.timers {"chrome":"54","ie":"10","node":"6"}
+  web.immediate {"chrome":"54","ie":"10","node":"6"}
+  web.dom.iterable {"chrome":"54","ie":"10","node":"6"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/electron/stdout.txt b/test/debug-fixtures/electron/stdout.txt
index c1128e45..1d3da440 100644
--- a/test/debug-fixtures/electron/stdout.txt
+++ b/test/debug-fixtures/electron/stdout.txt
@@ -1,69 +1,77 @@
+Warning, the following targets are using a decimal version:
+
+  electron: 0.36
+
+We recommend using a string for minor/patch versions to avoid numbers like 6.10
+getting parsed as 6.1, which can lead to unexpected behavior.
+
 babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "electron": 0.36
+  "electron": "0.36"
 }
 
 Modules transform: commonjs
 
 Using plugins:
-  check-es2015-constants {"electron":0.36}
-  transform-es2015-block-scoping {"electron":0.36}
-  transform-es2015-destructuring {"electron":0.36}
-  transform-es2015-for-of {"electron":0.36}
-  transform-es2015-function-name {"electron":0.36}
-  transform-es2015-parameters {"electron":0.36}
-  transform-es2015-sticky-regex {"electron":0.36}
-  transform-es2015-unicode-regex {"electron":0.36}
-  transform-regenerator {"electron":0.36}
-  transform-exponentiation-operator {"electron":0.36}
-  transform-async-to-generator {"electron":0.36}
-  syntax-trailing-function-commas {"electron":0.36}
+  check-es2015-constants {"electron":"0.36"}
+  transform-es2015-block-scoping {"electron":"0.36"}
+  transform-es2015-destructuring {"electron":"0.36"}
+  transform-es2015-for-of {"electron":"0.36"}
+  transform-es2015-function-name {"electron":"0.36"}
+  transform-es2015-parameters {"electron":"0.36"}
+  transform-es2015-sticky-regex {"electron":"0.36"}
+  transform-es2015-unicode-regex {"electron":"0.36"}
+  transform-regenerator {"electron":"0.36"}
+  transform-exponentiation-operator {"electron":"0.36"}
+  transform-async-to-generator {"electron":"0.36"}
+  syntax-trailing-function-commas {"electron":"0.36"}
 
 Using polyfills:
-  es6.typed.array-buffer {"electron":0.36}
-  es6.typed.int8-array {"electron":0.36}
-  es6.typed.uint8-array {"electron":0.36}
-  es6.typed.uint8-clamped-array {"electron":0.36}
-  es6.typed.int16-array {"electron":0.36}
-  es6.typed.uint16-array {"electron":0.36}
-  es6.typed.int32-array {"electron":0.36}
-  es6.typed.uint32-array {"electron":0.36}
-  es6.typed.float32-array {"electron":0.36}
-  es6.typed.float64-array {"electron":0.36}
-  es6.map {"electron":0.36}
-  es6.set {"electron":0.36}
-  es6.weak-map {"electron":0.36}
-  es6.weak-set {"electron":0.36}
-  es6.reflect.apply {"electron":0.36}
-  es6.reflect.construct {"electron":0.36}
-  es6.reflect.define-property {"electron":0.36}
-  es6.reflect.delete-property {"electron":0.36}
-  es6.reflect.get {"electron":0.36}
-  es6.reflect.get-own-property-descriptor {"electron":0.36}
-  es6.reflect.get-prototype-of {"electron":0.36}
-  es6.reflect.has {"electron":0.36}
-  es6.reflect.is-extensible {"electron":0.36}
-  es6.reflect.own-keys {"electron":0.36}
-  es6.reflect.prevent-extensions {"electron":0.36}
-  es6.reflect.set {"electron":0.36}
-  es6.reflect.set-prototype-of {"electron":0.36}
-  es6.promise {"electron":0.36}
-  es6.symbol {"electron":0.36}
-  es6.function.name {"electron":0.36}
-  es6.regexp.flags {"electron":0.36}
-  es6.regexp.match {"electron":0.36}
-  es6.regexp.replace {"electron":0.36}
-  es6.regexp.split {"electron":0.36}
-  es6.regexp.search {"electron":0.36}
-  es6.array.from {"electron":0.36}
-  es7.object.values {"electron":0.36}
-  es7.object.entries {"electron":0.36}
-  es7.object.get-own-property-descriptors {"electron":0.36}
-  es7.string.pad-start {"electron":0.36}
-  es7.string.pad-end {"electron":0.36}
-  web.timers {"electron":0.36}
-  web.immediate {"electron":0.36}
-  web.dom.iterable {"electron":0.36}
+  es6.typed.array-buffer {"electron":"0.36"}
+  es6.typed.data-view {"electron":"0.36"}
+  es6.typed.int8-array {"electron":"0.36"}
+  es6.typed.uint8-array {"electron":"0.36"}
+  es6.typed.uint8-clamped-array {"electron":"0.36"}
+  es6.typed.int16-array {"electron":"0.36"}
+  es6.typed.uint16-array {"electron":"0.36"}
+  es6.typed.int32-array {"electron":"0.36"}
+  es6.typed.uint32-array {"electron":"0.36"}
+  es6.typed.float32-array {"electron":"0.36"}
+  es6.typed.float64-array {"electron":"0.36"}
+  es6.map {"electron":"0.36"}
+  es6.set {"electron":"0.36"}
+  es6.weak-map {"electron":"0.36"}
+  es6.weak-set {"electron":"0.36"}
+  es6.reflect.apply {"electron":"0.36"}
+  es6.reflect.construct {"electron":"0.36"}
+  es6.reflect.define-property {"electron":"0.36"}
+  es6.reflect.delete-property {"electron":"0.36"}
+  es6.reflect.get {"electron":"0.36"}
+  es6.reflect.get-own-property-descriptor {"electron":"0.36"}
+  es6.reflect.get-prototype-of {"electron":"0.36"}
+  es6.reflect.has {"electron":"0.36"}
+  es6.reflect.is-extensible {"electron":"0.36"}
+  es6.reflect.own-keys {"electron":"0.36"}
+  es6.reflect.prevent-extensions {"electron":"0.36"}
+  es6.reflect.set {"electron":"0.36"}
+  es6.reflect.set-prototype-of {"electron":"0.36"}
+  es6.promise {"electron":"0.36"}
+  es6.symbol {"electron":"0.36"}
+  es6.function.name {"electron":"0.36"}
+  es6.regexp.flags {"electron":"0.36"}
+  es6.regexp.match {"electron":"0.36"}
+  es6.regexp.replace {"electron":"0.36"}
+  es6.regexp.split {"electron":"0.36"}
+  es6.regexp.search {"electron":"0.36"}
+  es6.array.from {"electron":"0.36"}
+  es7.object.values {"electron":"0.36"}
+  es7.object.entries {"electron":"0.36"}
+  es7.object.get-own-property-descriptors {"electron":"0.36"}
+  es7.string.pad-start {"electron":"0.36"}
+  es7.string.pad-end {"electron":"0.36"}
+  web.timers {"electron":"0.36"}
+  web.immediate {"electron":"0.36"}
+  web.dom.iterable {"electron":"0.36"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/plugins-only/options.json b/test/debug-fixtures/plugins-only/options.json
index c04dc1ba..2b1d88bc 100644
--- a/test/debug-fixtures/plugins-only/options.json
+++ b/test/debug-fixtures/plugins-only/options.json
@@ -4,7 +4,8 @@
       "debug": true,
       "exclude": [
         "transform-async-to-generator",
-        "transform-regenerator", "transform-es2015-parameters"
+        "transform-regenerator",
+        "transform-es2015-parameters"
       ],
       "targets": {
         "firefox": 52,
diff --git a/test/debug-fixtures/plugins-only/stdout.txt b/test/debug-fixtures/plugins-only/stdout.txt
index a2ccd28b..d6672838 100644
--- a/test/debug-fixtures/plugins-only/stdout.txt
+++ b/test/debug-fixtures/plugins-only/stdout.txt
@@ -1,17 +1,24 @@
+Warning, the following targets are using a decimal version:
+
+  node: 7.4
+
+We recommend using a string for minor/patch versions to avoid numbers like 6.10
+getting parsed as 6.1, which can lead to unexpected behavior.
+
 babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "firefox": 52,
-  "node": 7.4
+  "firefox": "52",
+  "node": "7.4"
 }
 
 Modules transform: commonjs
 
 Using plugins:
-  transform-es2015-destructuring {"firefox":52}
-  transform-es2015-for-of {"firefox":52}
-  transform-es2015-function-name {"firefox":52}
-  transform-es2015-literals {"firefox":52}
-  syntax-trailing-function-commas {"node":7.4}
+  transform-es2015-destructuring {"firefox":"52"}
+  transform-es2015-for-of {"firefox":"52"}
+  transform-es2015-function-name {"firefox":"52"}
+  transform-es2015-literals {"firefox":"52"}
+  syntax-trailing-function-commas {"node":"7.4"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/specific-targets/stdout.txt b/test/debug-fixtures/specific-targets/stdout.txt
index fe07366e..2fed2817 100644
--- a/test/debug-fixtures/specific-targets/stdout.txt
+++ b/test/debug-fixtures/specific-targets/stdout.txt
@@ -2,125 +2,125 @@ babel-preset-env: `DEBUG` option
 
 Using targets:
 {
-  "chrome": 54,
-  "edge": 13,
-  "firefox": 49,
-  "ie": 10,
-  "ios": 9,
-  "safari": 7
+  "chrome": "54",
+  "edge": "13",
+  "firefox": "49",
+  "ie": "10",
+  "ios": "9",
+  "safari": "7"
 }
 
 Modules transform: commonjs
 
 Using plugins:
-  check-es2015-constants {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-arrow-functions {"ie":10,"ios":9,"safari":7}
-  transform-es2015-block-scoped-functions {"ie":10,"ios":9,"safari":7}
-  transform-es2015-block-scoping {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-classes {"ie":10,"ios":9,"safari":7}
-  transform-es2015-computed-properties {"ie":10,"safari":7}
-  transform-es2015-destructuring {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-duplicate-keys {"ie":10,"safari":7}
-  transform-es2015-for-of {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-function-name {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-literals {"firefox":49,"ie":10,"safari":7}
-  transform-es2015-object-super {"ie":10,"ios":9,"safari":7}
-  transform-es2015-parameters {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-es2015-shorthand-properties {"ie":10,"safari":7}
-  transform-es2015-spread {"ie":10,"ios":9,"safari":7}
-  transform-es2015-sticky-regex {"ie":10,"ios":9,"safari":7}
-  transform-es2015-template-literals {"ie":10,"safari":7}
-  transform-es2015-typeof-symbol {"ie":10,"safari":7}
-  transform-es2015-unicode-regex {"ie":10,"ios":9,"safari":7}
-  transform-regenerator {"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-exponentiation-operator {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  transform-async-to-generator {"chrome":54,"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  syntax-trailing-function-commas {"chrome":54,"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
+  check-es2015-constants {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-arrow-functions {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-block-scoped-functions {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-block-scoping {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-classes {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-computed-properties {"ie":"10","safari":"7"}
+  transform-es2015-destructuring {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-duplicate-keys {"ie":"10","safari":"7"}
+  transform-es2015-for-of {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-function-name {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-literals {"firefox":"49","ie":"10","safari":"7"}
+  transform-es2015-object-super {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-parameters {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-es2015-shorthand-properties {"ie":"10","safari":"7"}
+  transform-es2015-spread {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-sticky-regex {"ie":"10","ios":"9","safari":"7"}
+  transform-es2015-template-literals {"ie":"10","safari":"7"}
+  transform-es2015-typeof-symbol {"ie":"10","safari":"7"}
+  transform-es2015-unicode-regex {"ie":"10","ios":"9","safari":"7"}
+  transform-regenerator {"firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-exponentiation-operator {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  transform-async-to-generator {"chrome":"54","edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  syntax-trailing-function-commas {"chrome":"54","edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
 
 Using polyfills:
-  es6.typed.array-buffer {"ie":10,"ios":9,"safari":7}
-  es6.typed.int8-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.uint8-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.uint8-clamped-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.int16-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.uint16-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.int32-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.uint32-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.float32-array {"ie":10,"ios":9,"safari":7}
-  es6.typed.float64-array {"ie":10,"ios":9,"safari":7}
-  es6.map {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  es6.set {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  es6.weak-map {"edge":13,"firefox":49,"ie":10,"safari":7}
-  es6.weak-set {"edge":13,"firefox":49,"ie":10,"safari":7}
-  es6.reflect.apply {"ie":10,"ios":9,"safari":7}
-  es6.reflect.construct {"ie":10,"ios":9,"safari":7}
-  es6.reflect.define-property {"ie":10,"ios":9,"safari":7}
-  es6.reflect.delete-property {"ie":10,"ios":9,"safari":7}
-  es6.reflect.get {"ie":10,"ios":9,"safari":7}
-  es6.reflect.get-own-property-descriptor {"ie":10,"ios":9,"safari":7}
-  es6.reflect.get-prototype-of {"ie":10,"ios":9,"safari":7}
-  es6.reflect.has {"ie":10,"ios":9,"safari":7}
-  es6.reflect.is-extensible {"ie":10,"ios":9,"safari":7}
-  es6.reflect.own-keys {"ie":10,"ios":9,"safari":7}
-  es6.reflect.prevent-extensions {"ie":10,"ios":9,"safari":7}
-  es6.reflect.set {"ie":10,"ios":9,"safari":7}
-  es6.reflect.set-prototype-of {"ie":10,"ios":9,"safari":7}
-  es6.promise {"ie":10,"ios":9,"safari":7}
-  es6.symbol {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  es6.object.assign {"ie":10,"safari":7}
-  es6.object.is {"ie":10,"safari":7}
-  es6.object.set-prototype-of {"ie":10,"safari":7}
-  es6.function.name {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  es6.string.raw {"ie":10,"safari":7}
-  es6.string.from-code-point {"ie":10,"safari":7}
-  es6.string.code-point-at {"ie":10,"safari":7}
-  es6.string.repeat {"ie":10,"safari":7}
-  es6.string.starts-with {"ie":10,"safari":7}
-  es6.string.ends-with {"ie":10,"safari":7}
-  es6.string.includes {"ie":10,"safari":7}
-  es6.regexp.flags {"edge":13,"ie":10,"safari":7}
-  es6.regexp.match {"edge":13,"ie":10,"ios":9,"safari":7}
-  es6.regexp.replace {"edge":13,"ie":10,"ios":9,"safari":7}
-  es6.regexp.split {"edge":13,"ie":10,"ios":9,"safari":7}
-  es6.regexp.search {"edge":13,"ie":10,"ios":9,"safari":7}
-  es6.array.from {"edge":13,"ie":10,"ios":9,"safari":7}
-  es6.array.of {"ie":10,"safari":7}
-  es6.array.copy-within {"ie":10,"safari":7}
-  es6.array.find {"ie":10,"safari":7}
-  es6.array.find-index {"ie":10,"safari":7}
-  es6.array.fill {"ie":10,"safari":7}
-  es6.array.iterator {"ie":10,"safari":7}
-  es6.number.is-finite {"ie":10,"safari":7}
-  es6.number.is-integer {"ie":10,"safari":7}
-  es6.number.is-safe-integer {"ie":10,"safari":7}
-  es6.number.is-nan {"ie":10,"safari":7}
-  es6.number.epsilon {"ie":10,"safari":7}
-  es6.number.min-safe-integer {"ie":10,"safari":7}
-  es6.number.max-safe-integer {"ie":10,"safari":7}
-  es6.math.acosh {"ie":10,"safari":7}
-  es6.math.asinh {"ie":10,"safari":7}
-  es6.math.atanh {"ie":10,"safari":7}
-  es6.math.cbrt {"ie":10,"safari":7}
-  es6.math.clz32 {"ie":10,"safari":7}
-  es6.math.cosh {"ie":10,"safari":7}
-  es6.math.expm1 {"ie":10,"safari":7}
-  es6.math.fround {"ie":10,"safari":7}
-  es6.math.hypot {"ie":10,"safari":7}
-  es6.math.imul {"ie":10}
-  es6.math.log1p {"ie":10,"safari":7}
-  es6.math.log10 {"ie":10,"safari":7}
-  es6.math.log2 {"ie":10,"safari":7}
-  es6.math.sign {"ie":10,"safari":7}
-  es6.math.sinh {"ie":10,"safari":7}
-  es6.math.tanh {"ie":10,"safari":7}
-  es6.math.trunc {"ie":10,"safari":7}
-  es7.array.includes {"edge":13,"ie":10,"ios":9,"safari":7}
-  es7.object.values {"edge":13,"ie":10,"ios":9,"safari":7}
-  es7.object.entries {"edge":13,"ie":10,"ios":9,"safari":7}
-  es7.object.get-own-property-descriptors {"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  es7.string.pad-start {"chrome":54,"edge":13,"ie":10,"ios":9,"safari":7}
-  es7.string.pad-end {"chrome":54,"edge":13,"ie":10,"ios":9,"safari":7}
-  web.timers {"chrome":54,"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  web.immediate {"chrome":54,"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
-  web.dom.iterable {"chrome":54,"edge":13,"firefox":49,"ie":10,"ios":9,"safari":7}
+  es6.typed.array-buffer {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.int8-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.uint8-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.uint8-clamped-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.int16-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.uint16-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.int32-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.uint32-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.float32-array {"ie":"10","ios":"9","safari":"7"}
+  es6.typed.float64-array {"ie":"10","ios":"9","safari":"7"}
+  es6.map {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  es6.set {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  es6.weak-map {"edge":"13","firefox":"49","ie":"10","safari":"7"}
+  es6.weak-set {"edge":"13","firefox":"49","ie":"10","safari":"7"}
+  es6.reflect.apply {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.construct {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.define-property {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.delete-property {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.get {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.get-own-property-descriptor {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.get-prototype-of {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.has {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.is-extensible {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.own-keys {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.prevent-extensions {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.set {"ie":"10","ios":"9","safari":"7"}
+  es6.reflect.set-prototype-of {"ie":"10","ios":"9","safari":"7"}
+  es6.promise {"ie":"10","ios":"9","safari":"7"}
+  es6.symbol {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  es6.object.assign {"ie":"10","safari":"7"}
+  es6.object.is {"ie":"10","safari":"7"}
+  es6.object.set-prototype-of {"ie":"10","safari":"7"}
+  es6.function.name {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  es6.string.raw {"ie":"10","safari":"7"}
+  es6.string.from-code-point {"ie":"10","safari":"7"}
+  es6.string.code-point-at {"ie":"10","safari":"7"}
+  es6.string.repeat {"ie":"10","safari":"7"}
+  es6.string.starts-with {"ie":"10","safari":"7"}
+  es6.string.ends-with {"ie":"10","safari":"7"}
+  es6.string.includes {"ie":"10","safari":"7"}
+  es6.regexp.flags {"edge":"13","ie":"10","safari":"7"}
+  es6.regexp.match {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es6.regexp.replace {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es6.regexp.split {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es6.regexp.search {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es6.array.from {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es6.array.of {"ie":"10","safari":"7"}
+  es6.array.copy-within {"ie":"10","safari":"7"}
+  es6.array.find {"ie":"10","safari":"7"}
+  es6.array.find-index {"ie":"10","safari":"7"}
+  es6.array.fill {"ie":"10","safari":"7"}
+  es6.array.iterator {"ie":"10","safari":"7"}
+  es6.number.is-finite {"ie":"10","safari":"7"}
+  es6.number.is-integer {"ie":"10","safari":"7"}
+  es6.number.is-safe-integer {"ie":"10","safari":"7"}
+  es6.number.is-nan {"ie":"10","safari":"7"}
+  es6.number.epsilon {"ie":"10","safari":"7"}
+  es6.number.min-safe-integer {"ie":"10","safari":"7"}
+  es6.number.max-safe-integer {"ie":"10","safari":"7"}
+  es6.math.acosh {"ie":"10","safari":"7"}
+  es6.math.asinh {"ie":"10","safari":"7"}
+  es6.math.atanh {"ie":"10","safari":"7"}
+  es6.math.cbrt {"ie":"10","safari":"7"}
+  es6.math.clz32 {"ie":"10","safari":"7"}
+  es6.math.cosh {"ie":"10","safari":"7"}
+  es6.math.expm1 {"ie":"10","safari":"7"}
+  es6.math.fround {"ie":"10","safari":"7"}
+  es6.math.hypot {"ie":"10","safari":"7"}
+  es6.math.imul {"ie":"10"}
+  es6.math.log1p {"ie":"10","safari":"7"}
+  es6.math.log10 {"ie":"10","safari":"7"}
+  es6.math.log2 {"ie":"10","safari":"7"}
+  es6.math.sign {"ie":"10","safari":"7"}
+  es6.math.sinh {"ie":"10","safari":"7"}
+  es6.math.tanh {"ie":"10","safari":"7"}
+  es6.math.trunc {"ie":"10","safari":"7"}
+  es7.array.includes {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es7.object.values {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es7.object.entries {"edge":"13","ie":"10","ios":"9","safari":"7"}
+  es7.object.get-own-property-descriptors {"edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  es7.string.pad-start {"chrome":"54","edge":"13","ie":"10","ios":"9","safari":"7"}
+  es7.string.pad-end {"chrome":"54","edge":"13","ie":"10","ios":"9","safari":"7"}
+  web.timers {"chrome":"54","edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  web.immediate {"chrome":"54","edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
+  web.dom.iterable {"chrome":"54","edge":"13","firefox":"49","ie":"10","ios":"9","safari":"7"}
 src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/versions-decimals/options.json b/test/debug-fixtures/versions-decimals/options.json
new file mode 100644
index 00000000..451949b4
--- /dev/null
+++ b/test/debug-fixtures/versions-decimals/options.json
@@ -0,0 +1,13 @@
+{
+  "presets": [
+    ["../../lib", {
+      "debug": true,
+      "targets": {
+        "chrome": 54,
+        "electron": 0.36,
+        "node": 6.10,
+        "ie": 10
+      }
+    }]
+  ]
+}
diff --git a/test/debug-fixtures/versions-decimals/stdout.txt b/test/debug-fixtures/versions-decimals/stdout.txt
new file mode 100644
index 00000000..4fd7b712
--- /dev/null
+++ b/test/debug-fixtures/versions-decimals/stdout.txt
@@ -0,0 +1,45 @@
+Warning, the following targets are using a decimal version:
+
+  electron: 0.36
+  node: 6.1
+
+We recommend using a string for minor/patch versions to avoid numbers like 6.10
+getting parsed as 6.1, which can lead to unexpected behavior.
+
+babel-preset-env: `DEBUG` option
+
+Using targets:
+{
+  "chrome": "54",
+  "electron": "0.36",
+  "node": "6.1",
+  "ie": "10"
+}
+
+Modules transform: commonjs
+
+Using plugins:
+  check-es2015-constants {"electron":"0.36","ie":"10"}
+  transform-es2015-arrow-functions {"ie":"10"}
+  transform-es2015-block-scoped-functions {"ie":"10"}
+  transform-es2015-block-scoping {"electron":"0.36","ie":"10"}
+  transform-es2015-classes {"ie":"10"}
+  transform-es2015-computed-properties {"ie":"10"}
+  transform-es2015-destructuring {"electron":"0.36","node":"6.1","ie":"10"}
+  transform-es2015-duplicate-keys {"ie":"10"}
+  transform-es2015-for-of {"electron":"0.36","node":"6.1","ie":"10"}
+  transform-es2015-function-name {"electron":"0.36","node":"6.1","ie":"10"}
+  transform-es2015-literals {"ie":"10"}
+  transform-es2015-object-super {"ie":"10"}
+  transform-es2015-parameters {"electron":"0.36","ie":"10"}
+  transform-es2015-shorthand-properties {"ie":"10"}
+  transform-es2015-spread {"ie":"10"}
+  transform-es2015-sticky-regex {"electron":"0.36","ie":"10"}
+  transform-es2015-template-literals {"ie":"10"}
+  transform-es2015-typeof-symbol {"ie":"10"}
+  transform-es2015-unicode-regex {"electron":"0.36","ie":"10"}
+  transform-regenerator {"electron":"0.36","ie":"10"}
+  transform-exponentiation-operator {"electron":"0.36","node":"6.1","ie":"10"}
+  transform-async-to-generator {"chrome":"54","electron":"0.36","node":"6.1","ie":"10"}
+  syntax-trailing-function-commas {"chrome":"54","electron":"0.36","node":"6.1","ie":"10"}
+src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/debug-fixtures/versions-strings/options.json b/test/debug-fixtures/versions-strings/options.json
new file mode 100644
index 00000000..0954a3ae
--- /dev/null
+++ b/test/debug-fixtures/versions-strings/options.json
@@ -0,0 +1,12 @@
+{
+  "presets": [
+    ["../../lib", {
+      "debug": true,
+      "targets": {
+        "chrome": "54",
+        "node": "6.10",
+        "ie": "10"
+      }
+    }]
+  ]
+}
diff --git a/test/debug-fixtures/versions-strings/stdout.txt b/test/debug-fixtures/versions-strings/stdout.txt
new file mode 100644
index 00000000..bd62d119
--- /dev/null
+++ b/test/debug-fixtures/versions-strings/stdout.txt
@@ -0,0 +1,36 @@
+babel-preset-env: `DEBUG` option
+
+Using targets:
+{
+  "chrome": "54",
+  "node": "6.10",
+  "ie": "10"
+}
+
+Modules transform: commonjs
+
+Using plugins:
+  check-es2015-constants {"ie":"10"}
+  transform-es2015-arrow-functions {"ie":"10"}
+  transform-es2015-block-scoped-functions {"ie":"10"}
+  transform-es2015-block-scoping {"ie":"10"}
+  transform-es2015-classes {"ie":"10"}
+  transform-es2015-computed-properties {"ie":"10"}
+  transform-es2015-destructuring {"ie":"10"}
+  transform-es2015-duplicate-keys {"ie":"10"}
+  transform-es2015-for-of {"ie":"10"}
+  transform-es2015-function-name {"ie":"10"}
+  transform-es2015-literals {"ie":"10"}
+  transform-es2015-object-super {"ie":"10"}
+  transform-es2015-parameters {"ie":"10"}
+  transform-es2015-shorthand-properties {"ie":"10"}
+  transform-es2015-spread {"ie":"10"}
+  transform-es2015-sticky-regex {"ie":"10"}
+  transform-es2015-template-literals {"ie":"10"}
+  transform-es2015-typeof-symbol {"ie":"10"}
+  transform-es2015-unicode-regex {"ie":"10"}
+  transform-regenerator {"ie":"10"}
+  transform-exponentiation-operator {"node":"6.10","ie":"10"}
+  transform-async-to-generator {"chrome":"54","node":"6.10","ie":"10"}
+  syntax-trailing-function-commas {"chrome":"54","node":"6.10","ie":"10"}
+src/in.js -> lib/in.js
\ No newline at end of file
diff --git a/test/fixtures/preset-options/electron/options.json b/test/fixtures/preset-options/electron/options.json
index 281c0fd3..26135107 100644
--- a/test/fixtures/preset-options/electron/options.json
+++ b/test/fixtures/preset-options/electron/options.json
@@ -2,7 +2,7 @@
   "presets": [
     ["../../../../lib", {
       "targets": {
-        "electron": 1.4
+        "electron": "1.4"
       },
       "modules": false,
       "useBuiltIns": true
diff --git a/test/fixtures/preset-options/no-transform/options.json b/test/fixtures/preset-options/no-transform/options.json
index de09fa3f..c35fc697 100644
--- a/test/fixtures/preset-options/no-transform/options.json
+++ b/test/fixtures/preset-options/no-transform/options.json
@@ -2,7 +2,7 @@
   "presets": [
     ["../../../../lib", {
       "targets": {
-        "chrome": 55
+        "chrome": "55"
       },
       "modules": false,
       "useBuiltIns": true
diff --git a/test/fixtures/preset-options/use-builtins-node-web/options.json b/test/fixtures/preset-options/use-builtins-node-web/options.json
index 7d156cdc..aca3540b 100644
--- a/test/fixtures/preset-options/use-builtins-node-web/options.json
+++ b/test/fixtures/preset-options/use-builtins-node-web/options.json
@@ -2,8 +2,8 @@
   "presets": [
     ["../../../../lib", {
       "targets": {
-        "chrome": 55,
-        "node": 7.6,
+        "chrome": "55",
+        "node": "7.6",
         "uglify": true
       },
       "modules": false,
diff --git a/test/fixtures/preset-options/use-builtins-node/options.json b/test/fixtures/preset-options/use-builtins-node/options.json
index cc2666d5..49ccb53f 100644
--- a/test/fixtures/preset-options/use-builtins-node/options.json
+++ b/test/fixtures/preset-options/use-builtins-node/options.json
@@ -2,7 +2,7 @@
   "presets": [
     ["../../../../lib", {
       "targets": {
-        "node": 7.6,
+        "node": "7.6",
         "uglify": true
       },
       "modules": false,
diff --git a/test/fixtures/preset-options/use-builtins-require/options.json b/test/fixtures/preset-options/use-builtins-require/options.json
index de09fa3f..c35fc697 100644
--- a/test/fixtures/preset-options/use-builtins-require/options.json
+++ b/test/fixtures/preset-options/use-builtins-require/options.json
@@ -2,7 +2,7 @@
   "presets": [
     ["../../../../lib", {
       "targets": {
-        "chrome": 55
+        "chrome": "55"
       },
       "modules": false,
       "useBuiltIns": true
diff --git a/test/index.spec.js b/test/index.spec.js
index d71735a8..6eea95cc 100644
--- a/test/index.spec.js
+++ b/test/index.spec.js
@@ -4,56 +4,11 @@ const babelPresetEnv = require("../lib/index.js");
 const assert = require("assert");
 
 describe("babel-preset-env", () => {
-  describe("getTargets", () => {
-    it("should return the current node version with option 'current'", function() {
-      assert.deepEqual(babelPresetEnv.getTargets({
-        node: true
-      }), {
-        node: parseFloat(process.versions.node)
-      });
-
-      assert.deepEqual(babelPresetEnv.getTargets({
-        node: "current"
-      }), {
-        node: parseFloat(process.versions.node)
-      });
-    });
-
-    it("transforms electron version to a number", function() {
-      assert.deepEqual(babelPresetEnv.getTargets({
-        electron: "1.2"
-      }), {
-        electron: 1.2
-      });
-    });
-  });
-
-  describe("getTargets + uglify", () => {
-    it("should work with `true`", function() {
-      assert.deepEqual(babelPresetEnv.getTargets({
-        uglify: true
-      }), {
-        uglify: true
-      });
-    });
-
-    it("should ignore `false`", function() {
-      assert.deepEqual(babelPresetEnv.getTargets({
-        uglify: false
-      }), {});
-    });
-
-    it("should ignore `null`", function() {
-      assert.deepEqual(babelPresetEnv.getTargets({
-        uglify: null
-      }), {});
-    });
-  });
-
   describe("isPluginRequired", () => {
+    const MAX_VERSION = `${Number.MAX_SAFE_INTEGER}.0.0`;
+
     it("returns true if no targets are specified", () => {
-      const isRequired = babelPresetEnv.isPluginRequired({}, {});
-      assert(isRequired);
+      assert.strictEqual(babelPresetEnv.isPluginRequired({}, {}), true);
     });
 
     it("returns true if plugin feature is not implemented in one or more targets", () => {
@@ -65,15 +20,21 @@ describe("babel-preset-env", () => {
       };
 
       targets = {
-        "chrome": Number.MAX_SAFE_INTEGER,
-        "firefox": Number.MAX_SAFE_INTEGER
+        chrome: MAX_VERSION,
+        firefox: MAX_VERSION,
       };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        false,
+      );
 
       targets = {
-        "edge": 12,
+        edge: "12",
       };
-      assert(babelPresetEnv.isPluginRequired(plugin, plugin) === true);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        true,
+      );
     });
 
     it("returns false if plugin feature is implemented by lower than target", () => {
@@ -81,9 +42,13 @@ describe("babel-preset-env", () => {
         chrome: 49,
       };
       const targets = {
-        "chrome": Number.MAX_SAFE_INTEGER,
+        chrome: MAX_VERSION,
       };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
+
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        false,
+      );
     });
 
     it("returns false if plugin feature is implemented is equal to target", () => {
@@ -91,9 +56,12 @@ describe("babel-preset-env", () => {
         chrome: 49,
       };
       const targets = {
-        "chrome": 49,
+        chrome: "49.0.0",
       };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        false,
+      );
     });
 
     it("returns true if plugin feature is implemented is greater than target", () => {
@@ -101,81 +69,49 @@ describe("babel-preset-env", () => {
         chrome: 50,
       };
       const targets = {
-        "chrome": 49,
-      };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
-    });
-
-    it("returns false if plugin feature is implemented by lower than target defined in browsers query", () => {
-      const plugin = {
-        chrome: 49,
-      };
-      const targets = {
-        "browsers": "chrome > 50"
+        chrome: "49.0.0",
       };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === false);
-    });
-
-    it("returns true if plugin feature is implemented is greater than target defined in browsers query", () => {
-      const plugin = {
-        chrome: 52,
-      };
-      const targets = {
-        "browsers": "chrome > 50"
-      };
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
-    });
-
-    it("returns true if target's root items overrides versions defined in browsers query", () => {
-      const plugin = {
-        chrome: 45,
-      };
-      const targets = {
-        browsers: "last 2 Chrome versions",
-        chrome: 44
-      };
-
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        true,
+      );
     });
 
     it("returns true if uglify is specified as a target", () => {
       const plugin = {
-        chrome: 50
+        chrome: 50,
       };
       const targets = {
-        chrome: 55,
-        uglify: true
+        chrome: "55.0.0",
+        uglify: true,
       };
-
-      assert(babelPresetEnv.isPluginRequired(targets, plugin) === true);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        true,
+      );
     });
 
-    it("doesn't throw when specifying a decimal for node", () => {
+    it("returns when target is a decimal", () => {
       const plugin = {
-        node: 6
+        node: 6.9,
       };
-
       const targets = {
-        "node": 6.5
+        node: "6.10.0",
       };
-
-      assert.doesNotThrow(() => {
-        babelPresetEnv.isPluginRequired(targets, plugin);
-      }, Error);
+      assert.strictEqual(
+        babelPresetEnv.isPluginRequired(targets, plugin),
+        false,
+      );
     });
 
-    it("will throw if target version is not a number", () => {
+    it("throws an error if target version is invalid", () => {
       const plugin = {
-        "node": 6,
+        chrome: 50,
       };
-
       const targets = {
-        "node": "6.5",
+        chrome: 55,
       };
-
-      assert.throws(() => {
-        babelPresetEnv.isPluginRequired(targets, plugin);
-      }, Error);
+      assert.throws(() => babelPresetEnv.isPluginRequired(targets, plugin));
     });
   });
 
diff --git a/test/targets-parser.spec.js b/test/targets-parser.spec.js
new file mode 100644
index 00000000..ff569174
--- /dev/null
+++ b/test/targets-parser.spec.js
@@ -0,0 +1,117 @@
+import assert from "assert";
+import getTargets from "../src/targets-parser";
+
+describe("getTargets", () => {
+  it("parses", () => {
+    assert.deepEqual(
+      getTargets({
+        chrome: 49,
+        firefox: "55",
+        ie: "9",
+        node: "6.10",
+        electron: "1.6",
+      }),
+      {
+        chrome: "49.0.0",
+        electron: "1.6.0",
+        firefox: "55.0.0",
+        ie: "9.0.0",
+        node: "6.10.0",
+      },
+    );
+  });
+
+  describe("browser", () => {
+    it("merges browser key targets", () => {
+      assert.deepEqual(
+        getTargets({
+          browsers: "chrome 56, ie 11, firefox 51, safari 9",
+          chrome: "49",
+          firefox: "55",
+          ie: "9",
+        }),
+        {
+          chrome: "49.0.0",
+          firefox: "51.0.0",
+          ie: "9.0.0",
+          safari: "9.0.0",
+        },
+      );
+    });
+
+    it("ignores invalid", () => {
+      assert.deepEqual(
+        getTargets({
+          browsers: 59,
+          chrome: "49",
+          firefox: "55",
+          ie: "11",
+        }),
+        {
+          chrome: "49.0.0",
+          firefox: "55.0.0",
+          ie: "11.0.0",
+        },
+      );
+    });
+  });
+
+  describe("node", () => {
+    it("should return the current node version with option 'current'", () => {
+      assert.deepEqual(
+        getTargets({
+          node: true,
+        }),
+        {
+          node: process.versions.node,
+        },
+      );
+    });
+  });
+
+  describe("electron", () => {
+    it("should be its own target", () => {
+      assert.deepEqual(
+        getTargets({
+          chrome: "46",
+          electron: "0.34",
+        }),
+        {
+          chrome: "46.0.0",
+          electron: "0.34.0",
+        },
+      );
+    });
+  });
+
+  describe("uglify", () => {
+    it("should work with `true`", function() {
+      assert.deepEqual(
+        getTargets({
+          uglify: true,
+        }),
+        {
+          uglify: true,
+        },
+      );
+    });
+
+    it("should ignore `false`", function() {
+      assert.deepEqual(
+        getTargets({
+          uglify: false,
+        }),
+        {},
+      );
+    });
+
+    it("should ignore `null`", function() {
+      assert.deepEqual(
+        getTargets({
+          uglify: null,
+        }),
+        {},
+      );
+    });
+  });
+});
diff --git a/test/utils.spec.js b/test/utils.spec.js
new file mode 100644
index 00000000..d3bcd765
--- /dev/null
+++ b/test/utils.spec.js
@@ -0,0 +1,61 @@
+"use strict";
+
+const utils = require("../lib/utils");
+const assert = require("assert");
+
+const {
+  prettifyTargets,
+  prettifyVersion,
+  semverify,
+} = utils;
+
+describe("utils", () => {
+  describe("semverify", () => {
+    it("returns", () => {
+      assert.strictEqual(semverify("1"), "1.0.0");
+      assert.strictEqual(semverify("1.0"), "1.0.0");
+      assert.strictEqual(semverify("1.0.0"), "1.0.0");
+      assert.strictEqual(semverify(1), "1.0.0");
+      assert.strictEqual(semverify(1.2), "1.2.0");
+    });
+  });
+
+  describe("prettifyVersion", () => {
+    it("returns", () => {
+      assert.strictEqual(prettifyVersion(true), true);
+      assert.strictEqual(prettifyVersion("0.16.0"), "0.16");
+      assert.strictEqual(prettifyVersion("1.0.0"), "1");
+      assert.strictEqual(prettifyVersion("1.1.0"), "1.1");
+      assert.strictEqual(prettifyVersion("1.0.2"), "1.0.2");
+      assert.strictEqual(prettifyVersion("1.2.3"), "1.2.3");
+    });
+  });
+
+  describe("prettifyTargets", () => {
+    it("returns", () => {
+      assert.deepEqual(prettifyTargets({}), {});
+
+      assert.deepEqual(
+        prettifyTargets({
+          uglify: true,
+        }),
+        {
+          uglify: true,
+        },
+      );
+
+      assert.deepEqual(
+        prettifyTargets({
+          chrome: "54.0.0",
+          electron: "1.6.0",
+          node: "0.12.0",
+        }),
+        {
+          chrome: "54",
+          electron: "1.6",
+          node: "0.12",
+        },
+      );
+    });
+  });
+});
diff --git a/yarn.lock b/yarn.lock
index 5e56c150..1fcd28cc 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -22,10 +22,6 @@ acorn-jsx@^3.0.0:
   dependencies:
     acorn "^3.0.4"
 
-acorn@4.0.4, acorn@^4.0.3:
-  version "4.0.4"
-  resolved "https://registry.yarnpkg.com/acorn/-/acorn-4.0.4.tgz#17a8d6a7a6c4ef538b814ec9abac2779293bf30a"
-
 acorn@^2.1.0, acorn@^2.4.0:
   version "2.7.0"
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-2.7.0.tgz#ab6e7d9d886aaca8b085bc3312b79a198433f0e7"
@@ -34,6 +30,10 @@ acorn@^3.0.4:
   version "3.3.0"
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-3.3.0.tgz#45e37fb39e8da3f25baee3ff5369e2bb5f22017a"
 
+acorn@^4.0.3:
+  version "4.0.4"
+  resolved "https://registry.yarnpkg.com/acorn/-/acorn-4.0.4.tgz#17a8d6a7a6c4ef538b814ec9abac2779293bf30a"
+
 acorn@^5.0.1:
   version "5.0.2"
   resolved "https://registry.yarnpkg.com/acorn/-/acorn-5.0.2.tgz#dc1c8fb907f64db2ab573de2326b73527c24de36"
@@ -233,31 +233,7 @@ babel-code-frame@^6.22.0:
     esutils "^2.0.2"
     js-tokens "^3.0.0"
 
-babel-core@^6.23.0:
-  version "6.23.1"
-  resolved "https://registry.yarnpkg.com/babel-core/-/babel-core-6.23.1.tgz#c143cb621bb2f621710c220c5d579d15b8a442df"
-  dependencies:
-    babel-code-frame "^6.22.0"
-    babel-generator "^6.23.0"
-    babel-helpers "^6.23.0"
-    babel-messages "^6.23.0"
-    babel-register "^6.23.0"
-    babel-runtime "^6.22.0"
-    babel-template "^6.23.0"
-    babel-traverse "^6.23.1"
-    babel-types "^6.23.0"
-    babylon "^6.11.0"
-    convert-source-map "^1.1.0"
-    debug "^2.1.1"
-    json5 "^0.5.0"
-    lodash "^4.2.0"
-    minimatch "^3.0.2"
-    path-is-absolute "^1.0.0"
-    private "^0.1.6"
-    slash "^1.0.0"
-    source-map "^0.5.0"
-
-babel-core@^6.24.0, babel-core@latest:
+babel-core@^6.23.0, babel-core@^6.24.0, babel-core@latest:
   version "6.24.0"
   resolved "https://registry.yarnpkg.com/babel-core/-/babel-core-6.24.0.tgz#8f36a0a77f5c155aed6f920b844d23ba56742a02"
   dependencies:
@@ -291,20 +267,7 @@ babel-eslint@^7.1.1:
     babylon "^6.13.0"
     lodash.pickby "^4.6.0"
 
-babel-generator@^6.18.0, babel-generator@^6.23.0:
-  version "6.23.0"
-  resolved "https://registry.yarnpkg.com/babel-generator/-/babel-generator-6.23.0.tgz#6b8edab956ef3116f79d8c84c5a3c05f32a74bc5"
-  dependencies:
-    babel-messages "^6.23.0"
-    babel-runtime "^6.22.0"
-    babel-types "^6.23.0"
-    detect-indent "^4.0.0"
-    jsesc "^1.3.0"
-    lodash "^4.2.0"
-    source-map "^0.5.0"
-    trim-right "^1.0.1"
-
-babel-generator@^6.24.0:
+babel-generator@^6.18.0, babel-generator@^6.24.0:
   version "6.24.0"
   resolved "https://registry.yarnpkg.com/babel-generator/-/babel-generator-6.24.0.tgz#eba270a8cc4ce6e09a61be43465d7c62c1f87c56"
   dependencies:
@@ -1717,14 +1680,7 @@ eslint@^3.17.1:
     text-table "~0.2.0"
     user-home "^2.0.0"
 
-espree@^3.4.0:
-  version "3.4.0"
-  resolved "https://registry.yarnpkg.com/espree/-/espree-3.4.0.tgz#41656fa5628e042878025ef467e78f125cb86e1d"
-  dependencies:
-    acorn "4.0.4"
-    acorn-jsx "^3.0.0"
-
-espree@latest:
+espree@^3.4.0, espree@latest:
   version "3.4.1"
   resolved "https://registry.yarnpkg.com/espree/-/espree-3.4.1.tgz#28a83ab4aaed71ed8fe0f5efe61b76a05c13c4d2"
   dependencies:

From 8fb22223e0d4b92da7698d66842a6513a5fac8d7 Mon Sep 17 00:00:00 2001
From: Brian Ng <bng412@gmail.com>
Date: Wed, 10 May 2017 14:53:15 -0500
Subject: [PATCH 2/2] Use ensureDirSync in smoke test

---
 scripts/smoke-test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/smoke-test.js b/scripts/smoke-test.js
index f845d6da..b5ad5ae9 100755
--- a/scripts/smoke-test.js
+++ b/scripts/smoke-test.js
@@ -13,7 +13,7 @@ try {
   execSync("npm pack");
 
   console.log("Setting up smoke test");
-  fs.ensureDir(tempFolderPath);
+  fs.ensureDirSync(tempFolderPath);
 
   fs.writeFileSync(
     path.join(tempFolderPath, "package.json"),