From 4c78984ad26825851d78d6f0339d8e4cb7bf1e54 Mon Sep 17 00:00:00 2001
From: Alan Agius <alan.agius4@gmail.com>
Date: Fri, 2 Jul 2021 12:33:51 +0200
Subject: [PATCH] fix(compiler-cli): support reflecting namespace declarations
 (#42728)
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DTS bundling, will cause originally namespaced imports become namespace declarations within the same file. Example:

Before bundling
```ts
import * as i1 from './router';

export declare class RouterModule {
    constructor(guard: any, router: Router);

    static ɵmod: i0.ɵɵNgModuleDeclaration<RouterModule, [typeof i1.RouterOutlet...]>;
}
```

After bundling
```
declare namespace i1 {
  export {
    RouterOutletContract,
    RouterOutlet
  }
}

export declare class RouterModule {
    constructor(guard: any, router: Router);

    static ɵmod: i0.ɵɵNgModuleDeclaration<RouterModule, [typeof i1.RouterOutlet...]>;
}
```

And therefore this commit adds support for reflecting types that are defined in such namespace declarations.

Closes #42064

PR Close #42728
---
 .../src/ngtsc/reflection/src/typescript.ts    |  2 ++
 .../src/ngtsc/reflection/test/ts_host_spec.ts | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/packages/compiler-cli/src/ngtsc/reflection/src/typescript.ts b/packages/compiler-cli/src/ngtsc/reflection/src/typescript.ts
index a08a088a68..7c3ebc6e56 100644
--- a/packages/compiler-cli/src/ngtsc/reflection/src/typescript.ts
+++ b/packages/compiler-cli/src/ngtsc/reflection/src/typescript.ts
@@ -548,6 +548,8 @@ export function reflectTypeEntityToDeclaration(
         throw new Error(`Module specifier is not a string`);
       }
       return {node, from: importDecl.moduleSpecifier.text};
+    } else if (ts.isModuleDeclaration(decl)) {
+      return {node, from: null};
     } else {
       throw new Error(`Unknown import type?`);
     }
diff --git a/packages/compiler-cli/src/ngtsc/reflection/test/ts_host_spec.ts b/packages/compiler-cli/src/ngtsc/reflection/test/ts_host_spec.ts
index d298d2441c..fd5c7c7ffb 100644
--- a/packages/compiler-cli/src/ngtsc/reflection/test/ts_host_spec.ts
+++ b/packages/compiler-cli/src/ngtsc/reflection/test/ts_host_spec.ts
@@ -153,6 +153,30 @@ runInEachFileSystem(() => {
         expectParameter(args[0], 'bar', {moduleName: './bar', name: 'Bar'});
       });
 
+      it('should reflect an argument from a namespace declarations', () => {
+        const {program} = makeProgram([{
+          name: _('/entry.ts'),
+          contents: `
+            export declare class Bar {}
+            declare namespace i1 {
+              export {
+                Bar,
+              }
+            }
+
+            class Foo {
+              constructor(bar: i1.Bar) {}
+            }
+        `
+        }]);
+        const clazz = getDeclaration(program, _('/entry.ts'), 'Foo', isNamedClassDeclaration);
+        const checker = program.getTypeChecker();
+        const host = new TypeScriptReflectionHost(checker);
+        const args = host.getConstructorParameters(clazz)!;
+        expect(args.length).toBe(1);
+        expectParameter(args[0], 'bar', 'i1.Bar');
+      });
+
       it('should reflect an argument from a default import', () => {
         const {program} = makeProgram([
           {