From 69e57827e2be7ca7164c428e32cb3ac187aaac3c Mon Sep 17 00:00:00 2001
From: JoostK <joost.koehoorn@gmail.com>
Date: Fri, 7 May 2021 22:53:30 +0200
Subject: [PATCH] refactor(compiler-cli): remove unused return type transform
 (#41996)

With the removal of the `ModuleWithProviders` transform in the parent commit,
the underlying dts transform can also be removed as it is not used elsewhere.

PR Close #41996
---
 .../compiler-cli/src/ngtsc/transform/index.ts |  2 +-
 .../src/ngtsc/transform/src/declaration.ts    | 59 -------------------
 2 files changed, 1 insertion(+), 60 deletions(-)

diff --git a/packages/compiler-cli/src/ngtsc/transform/index.ts b/packages/compiler-cli/src/ngtsc/transform/index.ts
index a3fe99dfe6..e3da19c3b1 100644
--- a/packages/compiler-cli/src/ngtsc/transform/index.ts
+++ b/packages/compiler-cli/src/ngtsc/transform/index.ts
@@ -9,6 +9,6 @@
 export * from './src/api';
 export {aliasTransformFactory} from './src/alias';
 export {ClassRecord, TraitCompiler} from './src/compilation';
-export {declarationTransformFactory, DtsTransformRegistry, IvyDeclarationDtsTransform, ReturnTypeTransform} from './src/declaration';
+export {declarationTransformFactory, DtsTransformRegistry, IvyDeclarationDtsTransform} from './src/declaration';
 export {AnalyzedTrait, PendingTrait, ResolvedTrait, SkippedTrait, Trait, TraitState} from './src/trait';
 export {ivyTransformFactory} from './src/transform';
diff --git a/packages/compiler-cli/src/ngtsc/transform/src/declaration.ts b/packages/compiler-cli/src/ngtsc/transform/src/declaration.ts
index f5f3c26e5a..4adeee9ddb 100644
--- a/packages/compiler-cli/src/ngtsc/transform/src/declaration.ts
+++ b/packages/compiler-cli/src/ngtsc/transform/src/declaration.ts
@@ -22,7 +22,6 @@ import {addImports} from './utils';
  */
 export class DtsTransformRegistry {
   private ivyDeclarationTransforms = new Map<ts.SourceFile, IvyDeclarationDtsTransform>();
-  private returnTypeTransforms = new Map<ts.SourceFile, ReturnTypeTransform>();
 
   getIvyDeclarationTransform(sf: ts.SourceFile): IvyDeclarationDtsTransform {
     if (!this.ivyDeclarationTransforms.has(sf)) {
@@ -31,13 +30,6 @@ export class DtsTransformRegistry {
     return this.ivyDeclarationTransforms.get(sf)!;
   }
 
-  getReturnTypeTransform(sf: ts.SourceFile): ReturnTypeTransform {
-    if (!this.returnTypeTransforms.has(sf)) {
-      this.returnTypeTransforms.set(sf, new ReturnTypeTransform());
-    }
-    return this.returnTypeTransforms.get(sf)!;
-  }
-
   /**
    * Gets the dts transforms to be applied for the given source file, or `null` if no transform is
    * necessary.
@@ -57,10 +49,6 @@ export class DtsTransformRegistry {
       transforms = [];
       transforms.push(this.ivyDeclarationTransforms.get(originalSf)!);
     }
-    if (this.returnTypeTransforms.has(originalSf)) {
-      transforms = transforms || [];
-      transforms.push(this.returnTypeTransforms.get(originalSf)!);
-    }
     return transforms;
   }
 }
@@ -230,50 +218,3 @@ function markForEmitAsSingleLine(node: ts.Node) {
   ts.setEmitFlags(node, ts.EmitFlags.SingleLine);
   ts.forEachChild(node, markForEmitAsSingleLine);
 }
-
-export class ReturnTypeTransform implements DtsTransform {
-  private typeReplacements = new Map<ts.Declaration, Type>();
-
-  addTypeReplacement(declaration: ts.Declaration, type: Type): void {
-    this.typeReplacements.set(declaration, type);
-  }
-
-  transformClassElement(element: ts.ClassElement, imports: ImportManager): ts.ClassElement {
-    if (ts.isMethodDeclaration(element)) {
-      const original = ts.getOriginalNode(element, ts.isMethodDeclaration);
-      if (!this.typeReplacements.has(original)) {
-        return element;
-      }
-      const returnType = this.typeReplacements.get(original)!;
-      const tsReturnType = translateType(returnType, imports);
-
-      return ts.updateMethod(
-          element, element.decorators, element.modifiers, element.asteriskToken, element.name,
-          element.questionToken, element.typeParameters, element.parameters, tsReturnType,
-          element.body);
-    }
-
-    return element;
-  }
-
-  transformFunctionDeclaration(element: ts.FunctionDeclaration, imports: ImportManager):
-      ts.FunctionDeclaration {
-    const original = ts.getOriginalNode(element) as ts.FunctionDeclaration;
-    if (!this.typeReplacements.has(original)) {
-      return element;
-    }
-    const returnType = this.typeReplacements.get(original)!;
-    const tsReturnType = translateType(returnType, imports);
-
-    return ts.updateFunctionDeclaration(
-        /* node */ element,
-        /* decorators */ element.decorators,
-        /* modifiers */ element.modifiers,
-        /* asteriskToken */ element.asteriskToken,
-        /* name */ element.name,
-        /* typeParameters */ element.typeParameters,
-        /* parameters */ element.parameters,
-        /* type */ tsReturnType,
-        /* body */ element.body);
-  }
-}