fix(ivy): ngcc: remove redundant `__decorate()` calls (#26236)

Previously we only removed assignments to `Class.decorators = [];`
if the array was not empty.

Now we also remove calls to `__decorate([])`, similarly.

PR Close #26236

packages/compiler-cli/src/ngcc/src/rendering/esm2015_renderer.ts

@@ -54,11 +54,11 @@ export class Esm2015Renderer extends Renderer {
       if (ts.isArrayLiteralExpression(containerNode)) {
         const items = containerNode.elements;
         if (items.length === nodesToRemove.length) {
-          // remove any trailing semi-colon
-          const end = (output.slice(containerNode.getEnd(), containerNode.getEnd() + 1) === ';') ?
-              containerNode.getEnd() + 1 :
-              containerNode.getEnd();
-          output.remove(containerNode.parent !.getFullStart(), end);
+          // Remove the entire statement
+          const statement = findStatement(containerNode);
+          if (statement) {
+            output.remove(statement.getFullStart(), statement.getEnd());
+          }
         } else {
           nodesToRemove.forEach(node => {
             // remove any trailing comma
@@ -82,3 +82,13 @@ export class Esm2015Renderer extends Renderer {
     });
   }
 }
+
+function findStatement(node: ts.Node) {
+  while (node) {
+    if (ts.isExpressionStatement(node)) {
+      return node;
+    }
+    node = node.parent;
+  }
+  return undefined;
+}

packages/compiler-cli/src/ngcc/test/rendering/esm2015_renderer_spec.ts

@@ -62,6 +62,44 @@ function compileNgModuleFactory__POST_NGCC__(injector, options, moduleType) {
 // Some other content`
 };
 
+const PROGRAM_DECORATE_HELPER = {
+  name: 'some/file.js',
+  contents: `
+import * as tslib_1 from "tslib";
+var D_1;
+/* A copyright notice */
+import { Directive } from '@angular/core';
+const OtherA = () => (node) => { };
+const OtherB = () => (node) => { };
+let A = class A {
+};
+A = tslib_1.__decorate([
+    Directive({ selector: '[a]' }),
+    OtherA()
+], A);
+export { A };
+let B = class B {
+};
+B = tslib_1.__decorate([
+    OtherB(),
+    Directive({ selector: '[b]' })
+], B);
+export { B };
+let C = class C {
+};
+C = tslib_1.__decorate([
+    Directive({ selector: '[c]' })
+], C);
+export { C };
+let D = D_1 = class D {
+};
+D = D_1 = tslib_1.__decorate([
+    Directive({ selector: '[d]', providers: [D_1] })
+], D);
+export { D };
+// Some other content`
+};
+
 describe('Esm2015Renderer', () => {
 
   describe('addImports', () => {
@@ -136,8 +174,9 @@ A.decorators = [
 
 
   describe('removeDecorators', () => {
-
-    it('should delete the decorator (and following comma) that was matched in the analysis', () => {
+    describe('[static property declaration]', () => {
+      it('should delete the decorator (and following comma) that was matched in the analysis',
+         () => {
            const {analyzer, parser, program, renderer} = setup(PROGRAM);
            const analyzedFile = analyze(parser, analyzer, program.getSourceFile(PROGRAM.name) !);
            const output = new MagicString(PROGRAM.contents);
@@ -146,7 +185,8 @@ A.decorators = [
            const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
            decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
            renderer.removeDecorators(output, decoratorsToRemove);
-      expect(output.toString()).not.toContain(`{ type: Directive, args: [{ selector: '[a]' }] },`);
+           expect(output.toString())
+               .not.toContain(`{ type: Directive, args: [{ selector: '[a]' }] },`);
            expect(output.toString()).toContain(`{ type: OtherA }`);
            expect(output.toString()).toContain(`{ type: Directive, args: [{ selector: '[b]' }] }`);
            expect(output.toString()).toContain(`{ type: OtherB }`);
@@ -173,7 +213,7 @@ A.decorators = [
          });
 
 
-    it('should delete the decorator (and its container if there are not other decorators left) that was matched in the analysis',
+      it('should delete the decorator (and its container if there are no other decorators left) that was matched in the analysis',
          () => {
            const {analyzer, parser, program, renderer} = setup(PROGRAM);
            const analyzedFile = analyze(parser, analyzer, program.getSourceFile(PROGRAM.name) !);
@@ -187,10 +227,68 @@ A.decorators = [
            expect(output.toString()).toContain(`{ type: OtherA }`);
            expect(output.toString()).toContain(`{ type: Directive, args: [{ selector: '[b]' }] }`);
            expect(output.toString()).toContain(`{ type: OtherB }`);
-         expect(output.toString()).not.toContain(`C.decorators = [
-  { type: Directive, args: [{ selector: '[c]' }] },
-];`);
+           expect(output.toString())
+               .not.toContain(`{ type: Directive, args: [{ selector: '[c]' }] }`);
+           expect(output.toString()).not.toContain(`C.decorators = [`);
+         });
+    });
   });
 
+  describe('[__decorate declarations]', () => {
+    it('should delete the decorator (and following comma) that was matched in the analysis', () => {
+      const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+      const analyzedFile =
+          analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+      const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+      const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'A') !;
+      const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+      const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+      decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+      renderer.removeDecorators(output, decoratorsToRemove);
+      expect(output.toString()).not.toContain(`Directive({ selector: '[a]' }),`);
+      expect(output.toString()).toContain(`OtherA()`);
+      expect(output.toString()).toContain(`Directive({ selector: '[b]' })`);
+      expect(output.toString()).toContain(`OtherB()`);
+      expect(output.toString()).toContain(`Directive({ selector: '[c]' })`);
+    });
+
+    it('should delete the decorator (but cope with no trailing comma) that was matched in the analysis',
+       () => {
+         const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+         const analyzedFile =
+             analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+         const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+         const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'B') !;
+         const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+         const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+         decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+         renderer.removeDecorators(output, decoratorsToRemove);
+         expect(output.toString()).toContain(`Directive({ selector: '[a]' }),`);
+         expect(output.toString()).toContain(`OtherA()`);
+         expect(output.toString()).not.toContain(`Directive({ selector: '[b]' })`);
+         expect(output.toString()).toContain(`OtherB()`);
+         expect(output.toString()).toContain(`Directive({ selector: '[c]' })`);
+       });
+
+
+    it('should delete the decorator (and its container if there are not other decorators left) that was matched in the analysis',
+       () => {
+         const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+         const analyzedFile =
+             analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+         const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+         const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'C') !;
+         const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+         const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+         decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+         renderer.removeDecorators(output, decoratorsToRemove);
+         expect(output.toString()).toContain(`Directive({ selector: '[a]' }),`);
+         expect(output.toString()).toContain(`OtherA()`);
+         expect(output.toString()).toContain(`Directive({ selector: '[b]' })`);
+         expect(output.toString()).toContain(`OtherB()`);
+         expect(output.toString()).not.toContain(`Directive({ selector: '[c]' })`);
+         expect(output.toString()).not.toContain(`C = tslib_1.__decorate([`);
+         expect(output.toString()).toContain(`let C = class C {\n};\nexport { C };`);
+       });
   });
 });

packages/compiler-cli/src/ngcc/test/rendering/esm5_renderer_spec.ts

@@ -74,6 +74,57 @@ function compileNgModuleFactory__POST_NGCC__(injector, options, moduleType) {
 export {A, B, C};`
 };
 
+const PROGRAM_DECORATE_HELPER = {
+  name: 'some/file.js',
+  contents: `
+import * as tslib_1 from "tslib";
+/* A copyright notice */
+import { Directive } from '@angular/core';
+var OtherA = function () { return function (node) { }; };
+var OtherB = function () { return function (node) { }; };
+var A = /** @class */ (function () {
+    function A() {
+    }
+    A = tslib_1.__decorate([
+        Directive({ selector: '[a]' }),
+        OtherA()
+    ], A);
+    return A;
+}());
+export { A };
+var B = /** @class */ (function () {
+    function B() {
+    }
+    B = tslib_1.__decorate([
+        OtherB(),
+        Directive({ selector: '[b]' })
+    ], B);
+    return B;
+}());
+export { B };
+var C = /** @class */ (function () {
+    function C() {
+    }
+    C = tslib_1.__decorate([
+        Directive({ selector: '[c]' })
+    ], C);
+    return C;
+}());
+export { C };
+var D = /** @class */ (function () {
+    function D() {
+    }
+    D_1 = D;
+    var D_1;
+    D = D_1 = tslib_1.__decorate([
+        Directive({ selector: '[d]', providers: [D_1] })
+    ], D);
+    return D;
+}());
+export { D };
+// Some other content`
+};
+
 describe('Esm5Renderer', () => {
 
   describe('addImports', () => {
@@ -205,4 +256,62 @@ SOME DEFINITION TEXT
        });
 
   });
+
+  describe('[__decorate declarations]', () => {
+    it('should delete the decorator (and following comma) that was matched in the analysis', () => {
+      const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+      const analyzedFile =
+          analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+      const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+      const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'A') !;
+      const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+      const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+      decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+      renderer.removeDecorators(output, decoratorsToRemove);
+      expect(output.toString()).not.toContain(`Directive({ selector: '[a]' }),`);
+      expect(output.toString()).toContain(`OtherA()`);
+      expect(output.toString()).toContain(`Directive({ selector: '[b]' })`);
+      expect(output.toString()).toContain(`OtherB()`);
+      expect(output.toString()).toContain(`Directive({ selector: '[c]' })`);
+    });
+
+    it('should delete the decorator (but cope with no trailing comma) that was matched in the analysis',
+       () => {
+         const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+         const analyzedFile =
+             analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+         const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+         const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'B') !;
+         const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+         const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+         decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+         renderer.removeDecorators(output, decoratorsToRemove);
+         expect(output.toString()).toContain(`Directive({ selector: '[a]' }),`);
+         expect(output.toString()).toContain(`OtherA()`);
+         expect(output.toString()).not.toContain(`Directive({ selector: '[b]' })`);
+         expect(output.toString()).toContain(`OtherB()`);
+         expect(output.toString()).toContain(`Directive({ selector: '[c]' })`);
+       });
+
+
+    it('should delete the decorator (and its container if there are no other decorators left) that was matched in the analysis',
+       () => {
+         const {analyzer, parser, program, renderer} = setup(PROGRAM_DECORATE_HELPER);
+         const analyzedFile =
+             analyze(parser, analyzer, program.getSourceFile(PROGRAM_DECORATE_HELPER.name) !);
+         const output = new MagicString(PROGRAM_DECORATE_HELPER.contents);
+         const analyzedClass = analyzedFile.analyzedClasses.find(c => c.name === 'C') !;
+         const decorator = analyzedClass.decorators.find(d => d.name === 'Directive') !;
+         const decoratorsToRemove = new Map<ts.Node, ts.Node[]>();
+         decoratorsToRemove.set(decorator.node.parent !, [decorator.node]);
+         renderer.removeDecorators(output, decoratorsToRemove);
+         expect(output.toString()).toContain(`Directive({ selector: '[a]' }),`);
+         expect(output.toString()).toContain(`OtherA()`);
+         expect(output.toString()).toContain(`Directive({ selector: '[b]' })`);
+         expect(output.toString()).toContain(`OtherB()`);
+         expect(output.toString()).not.toContain(`Directive({ selector: '[c]' })`);
+         expect(output.toString()).not.toContain(`C = tslib_1.__decorate([`);
+         expect(output.toString()).toContain(`function C() {\n    }\n    return C;`);
+       });
+  });
 });