Added support for parsing/processing TypeScript

package.json

@@ -74,6 +74,7 @@
     "@babel/plugin-transform-runtime": "^7.4.4",
     "@babel/preset-env": "^7.4.5",
     "@babel/preset-react": "^7.0.0",
+    "@babel/preset-typescript": "^7.3.3",
     "@loadable/babel-plugin": "^5.10.0",
     "app-root-dir": "^1.0.2",
     "babel-plugin-dynamic-import-node": "^2.2.0",

src/index.js

@@ -9,6 +9,7 @@ import importsPart from "./parts/imports"
 import proposalsPart from "./parts/proposals"
 import reactPart from "./parts/react"
 import shouldPrintComment from "./shouldPrintComment"
+import typescriptPart from "./parts/typescript"
 
 export default function buildPreset(context, input) {
   const options = getOptions(input)
@@ -37,6 +38,7 @@ export default function buildPreset(context, input) {
   compressionPart(presets, plugins, options)
   reactPart(presets, plugins, options)
   envPart(presets, plugins, options)
+  typescriptPart(presets, plugins, options)
 
   // Assemble final config
   return {

src/parts/typescript.js

@@ -0,0 +1,12 @@
+import typescriptPreset from "@babel/preset-typescript"
+
+export default function typescript(presets, plugins, options) {
+  presets.push([
+    typescriptPreset,
+    {
+      isTSX: true,
+      jsxPragma: options.jsxPragma,
+      allExtensions: true
+    }
+  ])
+}