fix(transform): undefined exports (regression #19)

.changeset/nine-melons-protect.md

@@ -0,0 +1,8 @@
+---
+'@wyw-in-js/transform': patch
+'@wyw-in-js/vite': patch
+'@wyw-in-js/cli': patch
+'wyw-in-js': patch
+---
+
+Fix regression from #19 that kills some exports.

packages/transform/src/__tests__/__snapshots__/shaker.test.ts.snap

@@ -0,0 +1,17 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`shaker should carefully shake used exports 1`] = `
+""use strict";
+
+var _activeClass;
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.activeClass = void 0;
+_activeClass = "s1gxjcbn";
+const _exp = /*#__PURE__*/() => _activeClass;
+exports.__wywPreval = {
+  _exp: _exp
+};
+exports.activeClass = _activeClass;"
+`;

packages/transform/src/__tests__/shaker.test.ts

@@ -0,0 +1,55 @@
+import { join } from 'path';
+
+import * as babel from '@babel/core';
+import dedent from 'dedent';
+
+import { shaker } from '../shaker';
+
+const run = (only: string[]) => (code: TemplateStringsArray) => {
+  const filename = join(__dirname, 'source.ts');
+  const formattedCode = dedent(code);
+  const parsed = babel.parseSync(formattedCode, {
+    filename,
+  });
+
+  return shaker(
+    {
+      filename,
+      plugins: [],
+    },
+    parsed!,
+    formattedCode,
+    {
+      features: {
+        dangerousCodeRemover: true,
+        globalCache: false,
+        happyDOM: false,
+        softErrors: false,
+        useBabelConfigs: false,
+      },
+      highPriorityPlugins: [],
+      onlyExports: only,
+    },
+    babel
+  )[1];
+};
+
+describe('shaker', () => {
+  it('should carefully shake used exports', () => {
+    const code = run(['__wywPreval'])`
+      "use strict";
+
+      Object.defineProperty(exports, "__esModule", {
+        value: true
+      });
+      exports.activeClass = void 0;
+      exports.activeClass = "s1gxjcbn";
+      const _exp = /*#__PURE__*/() => exports.activeClass;
+      exports.__wywPreval = {
+        _exp: _exp,
+      };
+    `;
+
+    expect(code).toMatchSnapshot();
+  });
+});

packages/transform/src/shaker.ts

@@ -20,7 +20,7 @@ const safeResolve = (id: string, paths: (string | null)[]): string | null => {
   }
 };
 
-const shaker: Evaluator = (
+export const shaker: Evaluator = (
   evalConfig,
   ast,
   code,

packages/transform/src/transform/generators/transform.ts

@@ -112,6 +112,7 @@ export const prepareCode = (
 
   log('[preeval] metadata %O', transformMetadata);
   log('[evaluator:start] using %s', evaluator.name);
+  log.extend('source')('%s', preevalStageResult.code!);
 
   const evaluatorConfig: EvaluatorConfig = {
     onlyExports: only,

packages/transform/src/utils/collectExportsAndImports.ts

@@ -794,6 +794,19 @@ function addExport(path: NodePath, exported: string, state: ILocalState): void {
   }
 }
 
+const saveRef = (
+  state: ILocalState,
+  exportName: string,
+  memberExpression: NodePath<MemberExpression>
+) => {
+  // Save all export.____ usages for later
+  if (!state.exportRefs.has(exportName)) {
+    state.exportRefs.set(exportName, []);
+  }
+
+  state.exportRefs.get(exportName)!.push(memberExpression);
+};
+
 function collectFromExports(
   path: NodePath<Identifier>,
   state: ILocalState
@@ -810,15 +823,6 @@ function collectFromExports(
 
     const exportName = property.node.name;
 
-    const saveRef = () => {
-      // Save all export.____ usages for later
-      if (!state.exportRefs.has(exportName)) {
-        state.exportRefs.set(exportName, []);
-      }
-
-      state.exportRefs.get(exportName)!.push(memberExpression);
-    };
-
     const assignmentExpression = memberExpression.parentPath;
 
     if (
@@ -827,7 +831,7 @@ function collectFromExports(
       })
     ) {
       // If it's not `exports.prop = …`. Just save it.
-      saveRef();
+      saveRef(state, exportName, memberExpression);
       return;
     }
 
@@ -844,7 +848,7 @@ function collectFromExports(
       return;
     }
 
-    saveRef();
+    saveRef(state, exportName, memberExpression);
     // eslint-disable-next-line no-param-reassign
     state.exports[property.node.name] = right;
 
@@ -1179,7 +1183,9 @@ function collectFromAssignmentExpression(
 
   let exported: IReexport['exported'] | undefined;
 
-  if (left.isMemberExpression() && isExports(left.get('object'))) {
+  const isExportRef =
+    left.isMemberExpression() && isExports(left.get('object'));
+  if (isExportRef) {
     const property = left.get('property');
     if (!left.node.computed && property.isIdentifier()) {
       exported = property.node.name;
@@ -1213,6 +1219,10 @@ function collectFromAssignmentExpression(
       state.exports[exported] = right;
     }
 
+    if (isExportRef) {
+      saveRef(state, exported, left);
+    }
+
     path.skip();
     return;
   }