fix(@angular-devkit/build-optimizer): fix decorator scrubbing with 2.4

Author: kara

packages/angular_devkit/build_optimizer/src/transforms/scrub-file.ts

@@ -56,9 +56,13 @@ export function getScrubFileTransformer(program: ts.Program): ts.TransformerFact
       const ngMetadata = findAngularMetadata(sf);
 
       const nodes: ts.Node[] = [];
-      ts.forEachChild(sf, (node) => {
+      ts.forEachChild(sf, checkNodeForDecorators);
+
+      function checkNodeForDecorators(node: ts.Node): void {
         if (node.kind !== ts.SyntaxKind.ExpressionStatement) {
-          return;
+          // TS 2.4 nests decorators inside downleveled class IIFEs, so we
+          // must recurse into them to find the relevant expression statements.
+          return ts.forEachChild(node, checkNodeForDecorators);
         }
         const exprStmt = node as ts.ExpressionStatement;
         if (isDecoratorAssignmentExpression(exprStmt)) {
@@ -71,7 +75,7 @@ export function getScrubFileTransformer(program: ts.Program): ts.TransformerFact
           && !isCtorParamsWhitelistedService(exprStmt)) {
           nodes.push(node);
         }
-      });
+      }
 
       const visitor: ts.Visitor = (node: ts.Node): ts.Node => {
         // Check if node is a statement to be dropped.

packages/angular_devkit/build_optimizer/src/transforms/scrub-file_spec.ts

@@ -17,7 +17,7 @@ describe('scrub-file', () => {
   const clazz = 'var Clazz = (function () { function Clazz() { } return Clazz; }());';
 
   describe('decorators', () => {
-    it('removes Angular decorators', () => {
+    it('removes top-level Angular decorators', () => {
       const output = stripIndent`
         import { Injectable } from '@angular/core';
         ${clazz}
@@ -31,6 +31,26 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
     });
 
+    it('removes nested Angular decorators', () => {
+      const output = stripIndent`
+        import { Injectable } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() { }
+          return Clazz;
+        }());
+      `;
+      const input = stripIndent`
+        import { Injectable } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() {}
+          Clazz.decorators = [ { type: Injectable } ];
+          return Clazz;
+        }());
+      `;
+
+      expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
+    });
+
     it('doesn\'t remove non Angular decorators', () => {
       const input = stripIndent`
         import { Injectable } from 'another-lib';
@@ -41,7 +61,7 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${input}`);
     });
 
-    it('leaves non-Angulars decorators in mixed arrays', () => {
+    it('leaves non-Angular decorators in mixed arrays', () => {
       const input = stripIndent`
         import { Injectable } from '@angular/core';
         import { NotInjectable } from 'another-lib';
@@ -60,7 +80,7 @@ describe('scrub-file', () => {
   });
 
   describe('propDecorators', () => {
-    it('removes Angular propDecorators', () => {
+    it('removes top-level Angular propDecorators', () => {
       const output = stripIndent`
         import { Input } from '@angular/core';
         ${clazz}
@@ -74,6 +94,26 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
     });
 
+    it('removes nested Angular propDecorators', () => {
+      const output = stripIndent`
+        import { Input } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() { }
+          return Clazz;
+        }());
+      `;
+      const input = stripIndent`
+        import { Input } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() {}
+          Clazz.propDecorators = { 'ngIf': [{ type: Input }] };
+          return Clazz;
+        }());
+      `;
+
+      expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
+    });
+
     it('doesn\'t remove non Angular propDecorators', () => {
       const input = stripIndent`
         import { Input } from 'another-lib';
@@ -84,7 +124,7 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${input}`);
     });
 
-    it('leaves non-Angulars propDecorators in mixed arrays', () => {
+    it('leaves non-Angular propDecorators in mixed arrays', () => {
       const output = stripIndent`
         import { Input } from '@angular/core';
         import { NotInput } from 'another-lib';
@@ -121,7 +161,7 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
     });
 
-    it('removes non-empty constructor parameters', () => {
+    it('removes non-empty top-level style constructor parameters', () => {
       const output = stripIndent`
         ${clazz}
       `;
@@ -133,6 +173,26 @@ describe('scrub-file', () => {
       expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
     });
 
+    it('removes nested constructor parameters', () => {
+      const output = stripIndent`
+        import { Injector } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() { }
+          return Clazz;
+        }());
+      `;
+      const input = stripIndent`
+        import { Injector } from '@angular/core';
+        var Clazz = (function () {
+          function Clazz() {}
+          Clazz.ctorParameters = function () { return [{type: Injector}]; };
+          return Clazz;
+        }());
+      `;
+
+      expect(oneLine`${transform(input)}`).toEqual(oneLine`${output}`);
+    });
+
     it('doesn\'t remove constructor parameters from whitelisted classes', () => {
       const input = stripIndent`
         ${clazz.replace('Clazz', 'PlatformRef_')}