Chore: Add webpack5 support (part 1) (#155)

- Update fixtures to support webpack5 and use dummy webpack/webpack-cli root packages approach from `webpack-stats-plugin`
- Note: Does not actually enable webpack5 in tests for #140 as there's a lot more work to do there, so we're capturing the intermediate work here.

package.json

@@ -88,20 +88,21 @@
     "mocha": "^8.2.1",
     "mock-fs": "^4.12.0",
     "nyc": "^15.0.1",
-    "raw-loader": "^4.0.1",
+    "raw-loader": "^4.0.2",
     "rimraf": "^3.0.2",
     "sinon": "^9.0.2",
     "sinon-chai": "^3.5.0",
     "source-map-support": "^0.5.19",
     "ts-node": "^9.1.1",
     "tslint": "^6.1.2",
     "typescript": "^4.1.3",
-    "webpack": "^4.43.0",
-    "webpack-cli": "^3.3.11",
-    "webpack-stats-plugin": "^0.3.1",
+    "webpack": "file:test/fixtures/packages/webpack",
+    "webpack-cli": "file:test/fixtures/packages/webpack-cli",
+    "webpack-stats-plugin": "^1.0.2",
     "webpack1": "file:test/fixtures/packages/webpack1",
     "webpack2": "file:test/fixtures/packages/webpack2",
     "webpack3": "file:test/fixtures/packages/webpack3",
-    "webpack4": "file:test/fixtures/packages/webpack4"
+    "webpack4": "file:test/fixtures/packages/webpack4",
+    "webpack5": "file:test/fixtures/packages/webpack5"
   }
 }

test/fixtures/packages/webpack-cli/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "webpack-cli",
+  "version": "0.0.0",
+  "description": "Empty package to prevent flattening of real package",
+  "license": "MIT"
+}

test/fixtures/packages/webpack/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "webpack",
+  "version": "0.0.0",
+  "description": "Empty package to prevent flattening of real package",
+  "license": "MIT"
+}

test/fixtures/packages/webpack4/index.js

@@ -5,4 +5,5 @@ if (process.env.DEBUG) {
   console.log(`webpack version: ${require("webpack/package.json").version}`);
 }
 
+// eslint-disable-next-line import/no-unresolved
 module.exports = require("webpack-cli");

test/fixtures/packages/webpack4/package.json

@@ -5,7 +5,7 @@
   "main": "index.js",
   "license": "MIT",
   "dependencies": {
-    "webpack": "^4.42.0",
+    "webpack": "^4.44.1",
     "webpack-cli": "^3.3.11"
   }
 }

test/fixtures/packages/webpack5/index.js

@@ -0,0 +1,10 @@
+
+
+if (process.env.DEBUG) {
+  // eslint-disable-next-line no-console
+  console.log(`webpack version: ${require("webpack/package.json").version}`);
+}
+
+// Note: Different than previous versions of webpack-cli.
+// eslint-disable-next-line import/no-unresolved
+module.exports = require("webpack-cli/bin/cli.js");

test/fixtures/packages/webpack5/lib.js

@@ -0,0 +1,7 @@
+if (process.env.DEBUG) {
+  // eslint-disable-next-line no-console
+  console.log(`webpack version: ${require("webpack/package.json").version}`);
+}
+
+// eslint-disable-next-line import/no-unresolved
+module.exports = require("webpack");

test/fixtures/packages/webpack5/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "webpack4",
+  "version": "0.0.1",
+  "description": "Webpack5 installs",
+  "main": "index.js",
+  "license": "MIT",
+  "dependencies": {
+    "webpack": "^5.1.0",
+    "webpack-cli": "^4.0.0"
+  }
+}