Fix options caching when ts-loader is used in multiple rules (#782)

src/index.ts

@@ -117,15 +117,21 @@ function getLoaderOptions(loader: Webpack) {
   const instanceName =
     webpackIndex + '_' + (loaderOptions.instance || 'default');
 
-  if (loaderOptionsCache.hasOwnProperty(instanceName)) {
-    return loaderOptionsCache[instanceName];
+  if (!loaderOptionsCache.hasOwnProperty(instanceName)) {
+    loaderOptionsCache[instanceName] = new WeakMap();
+  }
+
+  const cache = loaderOptionsCache[instanceName];
+
+  if (cache.has(loaderOptions)) {
+    return cache.get(loaderOptions) as LoaderOptions;
   }
 
   validateLoaderOptions(loaderOptions);
 
   const options = makeLoaderOptions(instanceName, loaderOptions);
 
-  loaderOptionsCache[instanceName] = options;
+  cache.set(loaderOptions, options);
 
   return options;
 }

src/interfaces.ts

@@ -258,7 +258,7 @@ export interface TSInstance {
 }
 
 export interface LoaderOptionsCache {
-  [name: string]: LoaderOptions;
+  [name: string]: WeakMap<LoaderOptions, LoaderOptions>;
 }
 
 export interface TSInstances {

test/execution-tests/optionsCaching/foo.ts

@@ -0,0 +1 @@
+import './foo.vue'

test/execution-tests/optionsCaching/foo.vue

@@ -0,0 +1,7 @@
+const React = {}
+
+export default {
+  render () {
+    return <div>hello</div>
+  }
+}

test/execution-tests/optionsCaching/tsconfig.json

@@ -0,0 +1,6 @@
+{
+	"compilerOptions": {
+    "target": "esnext",
+    "jsx": "react"
+  }
+}

test/execution-tests/optionsCaching/webpack.config.js

@@ -0,0 +1,25 @@
+var path = require('path')
+
+module.exports = {
+    mode: 'development',
+    entry: path.resolve(__dirname, 'foo.ts'),
+    output: {
+        path: __dirname,
+        filename: 'bundle.js'
+    },
+    module: {
+        rules: [
+            { test: /\.ts$/, loader: 'ts-loader', options: {} },
+            {
+                test: /\.vue$/,
+                loader: 'ts-loader',
+                options: {
+                    appendTsxSuffixTo: [/\.vue$/]
+                }
+            }
+        ]
+    }
+}
+
+// for test harness purposes only, you would not need this in a normal project
+module.exports.resolveLoader = { alias: { 'ts-loader': require('path').join(__dirname, "../../../index.js") } }