fix(shaker): partial support for ts compiled code (fixes #820)

packages/babel/__tests__/evaluators/__snapshots__/shaker.test.ts.snap

@@ -65,18 +65,6 @@ color.green = '#0f0';
 exports.__linariaPreval = [color];"
 `;
 
-exports[`keeps only the last assignment of each exported variable 1`] = `
-"\\"use strict\\";
-
-var bar = function bar() {
-  return 'hello world';
-};
-
-exports.bar = bar;
-var foo = exports.bar();
-exports.__linariaPreval = [foo];"
-`;
-
 exports[`keeps reused exports 1`] = `
 "\\"use strict\\";
 

packages/babel/__tests__/evaluators/shaker.test.ts

@@ -241,19 +241,3 @@ it('keeps reused exports', () => {
 
   expect(shaken).toMatchSnapshot();
 });
-
-it('keeps only the last assignment of each exported variable', () => {
-  const [shaken] = _shake()`
-    const bar = function() {
-      return 'hello world';
-    };
-
-    exports.bar = "bar";
-    exports.bar = bar;
-
-    const foo = exports.bar();
-    exports.__linariaPreval = [foo];
-  `;
-
-  expect(shaken).toMatchSnapshot();
-});

packages/shaker/src/DepsGraph.ts

@@ -77,6 +77,12 @@ export default class DepsGraph {
   }
 
   addExport(name: string, node: t.Node) {
+    const existed = this.exports.get(name);
+    if (existed) {
+      // Sometimes export can be defined more than once and in that case we have to keep all export statements
+      this.addEdge(node, existed);
+    }
+
     this.exports.set(name, node);
   }
 

packages/shaker/src/graphBuilder.ts

@@ -22,21 +22,23 @@ class GraphBuilder extends GraphBuilderState {
   }
 
   private isExportsIdentifier(node: Node) {
-    if (
-      t.isIdentifier(node) &&
-      this.scope.getDeclaration(node) === ScopeManager.globalExportsIdentifier
-    ) {
-      return true;
+    if (t.isIdentifier(node)) {
+      return (
+        this.scope.getDeclaration(node) === ScopeManager.globalExportsIdentifier
+      );
     }
 
-    return (
-      t.isMemberExpression(node) &&
-      t.isIdentifier(node.property) &&
-      node.property.name === 'exports' &&
-      t.isIdentifier(node.object) &&
-      this.scope.getDeclaration(node.object) ===
-        ScopeManager.globalModuleIdentifier
-    );
+    if (t.isMemberExpression(node)) {
+      return (
+        t.isIdentifier(node.property) &&
+        node.property.name === 'exports' &&
+        t.isIdentifier(node.object) &&
+        this.scope.getDeclaration(node.object) ===
+          ScopeManager.globalModuleIdentifier
+      );
+    }
+
+    return false;
   }
 
   private isExportsAssigment(node: Node): node is AssignmentExpression {
@@ -59,6 +61,17 @@ class GraphBuilder extends GraphBuilderState {
     return false;
   }
 
+  private isTSExporterCall(
+    node: Node
+  ): node is t.CallExpression & { arguments: [t.StringLiteral, t.Identifier] } {
+    if (!t.isCallExpression(node) || node.arguments.length !== 2) {
+      return false;
+    }
+
+    // FIXME: more precisely check
+    return !(!t.isIdentifier(node.callee) || node.callee.name !== 'exporter');
+  }
+
   /*
    * Implements a default behaviour for AST-nodes:
    * • visits every child;
@@ -158,6 +171,10 @@ class GraphBuilder extends GraphBuilderState {
           );
         }
       }
+    } else if (this.isTSExporterCall(node)) {
+      const [name, identifier] = node.arguments;
+      this.graph.addExport(name.value, node);
+      this.graph.addEdge(node, identifier);
     }
 
     const isScopable = t.isScopable(node);

packages/shaker/src/langs/core.ts

@@ -3,6 +3,7 @@ import type {
   AssignmentExpression,
   Block,
   CallExpression,
+  CatchClause,
   Directive,
   ExpressionStatement,
   ForInStatement,
@@ -75,6 +76,48 @@ function getCallee(node: CallExpression): Node {
   return node.callee;
 }
 
+function isTSLib(node: t.Node, scope: ScopeManager) {
+  if (!t.isIdentifier(node)) {
+    return false;
+  }
+
+  const declaration = scope.getDeclaration(node);
+  return t.isIdentifier(declaration) && declaration.name === 'tslib_1';
+}
+
+function isTSReexport(
+  node: t.Node,
+  scope: ScopeManager
+): node is t.Node & { callee: { object: t.Identifier } } {
+  if (!t.isCallExpression(node)) {
+    return false;
+  }
+
+  const {
+    callee,
+    arguments: [, exportsIdentifier],
+  } = node;
+  if (
+    !t.isIdentifier(exportsIdentifier) ||
+    exportsIdentifier.name !== 'exports' ||
+    scope.getDeclaration(exportsIdentifier) !==
+      ScopeManager.globalExportsIdentifier
+  ) {
+    return false;
+  }
+
+  if (!t.isMemberExpression(callee)) {
+    return false;
+  }
+
+  const { object, property } = callee;
+  if (!t.isIdentifier(property) || property.name !== '__exportStar') {
+    return false;
+  }
+
+  return isTSLib(object, scope);
+}
+
 function findWildcardReexportStatement(
   node: t.CallExpression,
   identifierName: string,
@@ -197,6 +240,10 @@ export const visitors: Visitors = {
       // keep function name in expressions like `const a = function a();`
       this.graph.addEdge(node, node.id);
     }
+
+    if (t.isFunctionDeclaration(node) && node.id) {
+      this.graph.addEdge(node, node.id);
+    }
   },
 
   /*
@@ -258,6 +305,12 @@ export const visitors: Visitors = {
     });
   },
 
+  CatchClause(this: GraphBuilderState, node: CatchClause) {
+    this.baseVisit(node);
+
+    this.graph.addEdge(node, node.body);
+  },
+
   IfStatement(this: GraphBuilderState, node: IfStatement) {
     this.baseVisit(node);
     this.graph.addEdge(node, node.consequent);
@@ -519,6 +572,18 @@ export const visitors: Visitors = {
         [Identifier, Identifier | null]
       >;
       if (!declared) {
+        // Is it a ts reexport?
+        // tslib_1.__exportStar(require("./Async"), exports);
+        if (parent && isTSReexport(parent, this.scope)) {
+          if (!this.graph.imports.has(source)) {
+            this.graph.imports.set(source, []);
+          }
+
+          this.graph.addEdge(parent.callee.object, parent);
+          this.graph.reexports.push(parent.callee.object);
+          this.graph.importTypes.set(source, 'reexport');
+        }
+
         // This is a standalone `require`
         return;
       }

packages/shaker/src/scope.ts

@@ -56,6 +56,8 @@ const getId = (scope: Scope, identifier: t.Identifier | string): string => {
   }`;
 };
 
+const globalIdentifiers = new Set(['exports', 'module']);
+
 export default class ScopeManager {
   public static globalExportsIdentifier = t.identifier('exports');
   public static globalModuleIdentifier = t.identifier('module');
@@ -125,7 +127,7 @@ export default class ScopeManager {
     const scope = this.stack
       .slice(stack)
       .find((s) => !isHoistable || functionScopes.has(s))!;
-    if (this.global.has(idName)) {
+    if (this.global.has(idName) && !globalIdentifiers.has(idName)) {
       // It's probably a declaration of a previous referenced identifier
       // Let's use naïve implementation of hoisting
       const promise = this.declarations.get(