test: add test with module content

Author: vankop

Diff for: test/__mocks__/webpack.js

@@ -1,7 +1,4 @@
-import { getCompiler, compile } from './helpers';
-
-jest.mock('webpack');
-jest.mock('webpack/lib/node/NodeTargetPlugin');
+import { getCompiler, source, compile } from './helpers';
 
 it('should enforce esm for empty module with options.esModule', async (done) => {
   const compiler = getCompiler(
@@ -14,18 +11,14 @@ it('should enforce esm for empty module with options.esModule', async (done) =>
   );
   const stats = await compile(compiler);
   expect(stats.hasErrors()).toBe(false);
-
-  const { chunks } = stats.toJson();
-  const [chunk] = chunks;
-
-  expect(JSON.stringify(chunk.sizes)).toMatchInlineSnapshot(
-    // javascript size is mostly a webpack info comments
-    `"{\\"javascript\\":73,\\"unknown\\":23,\\"runtime\\":0}"`
-  );
+  expect(source('./simple.css', stats)).toMatchInlineSnapshot(`
+    "// extracted by mini-css-extract-plugin
+    export {};"
+  `);
   done();
 });
 
-it('should keep module without options.esModule', async (done) => {
+it('should keep empty module without options.esModule', async (done) => {
   const compiler = getCompiler(
     './esm.js',
     {},
@@ -36,13 +29,8 @@ it('should keep module without options.esModule', async (done) => {
   );
   const stats = await compile(compiler);
   expect(stats.hasErrors()).toBe(false);
-
-  const { chunks } = stats.toJson();
-  const [chunk] = chunks;
-
-  expect(JSON.stringify(chunk.sizes)).toMatchInlineSnapshot(
-    // javascript size is mostly a webpack info comments
-    `"{\\"javascript\\":62,\\"unknown\\":23,\\"runtime\\":657}"`
+  expect(source('./simple.css', stats)).toMatchInlineSnapshot(
+    `"// extracted by mini-css-extract-plugin"`
   );
   done();
 });

Diff for: test/__mocks__/webpack/lib/node/NodeTargetPlugin.js

@@ -1,4 +1,5 @@
 import compile from './compile';
 import getCompiler from './getCompiler';
+import source from './source';
 
-export { compile, getCompiler };
+export { source, compile, getCompiler };

Diff for: test/enforce-esm.test.js

@@ -0,0 +1,19 @@
+export default function getSource(name, stats) {
+  const { modules } = stats.toJson({ source: true });
+
+  for (let i = 0; i < modules.length; i++) {
+    const module = modules[i];
+
+    if (module.modules && module.modules.length > 0) {
+      for (let j = 0; j < module.modules.length; j++) {
+        if (module.modules[j].name === name) {
+          return module.modules[j].source;
+        }
+      }
+    } else if (module.name === name) {
+      return module.source;
+    }
+  }
+
+  return undefined;
+}