feat(ivy): support NgModule metadata from calls that do not return ModuleWithProviders types (#27326)

Normally functions that return `ModuleWithProvider` objects should parameterize
the return type to include the type of `NgModule` that is being returned. For
example `forRoot(): ModuleWithProviders<RouterModule>`.

But in some cases, especially those generated by nccc, these functions to not
explicitly declare `ModuleWithProviders` as their return type. Instead they
return a "intersection" type, one of whose members is a type literal that
declares the `NgModule` type returned. For example:
`forRoot(): CustomType&{ngModule:RouterModule}`.

This commit changes the `NgModuleDecoratorHandler` so that it can extract
the `NgModule` type from either kind of declaration.

PR Close #27326

packages/compiler-cli/src/ngtsc/annotations/src/ng_module.ts

@@ -197,9 +197,20 @@ export class NgModuleDecoratorHandler implements DecoratorHandler<NgModuleAnalys
    */
   private _extractModuleFromModuleWithProvidersFn(node: ts.FunctionDeclaration|
                                                   ts.MethodDeclaration): ts.Expression|null {
-    const type = node.type;
+    const type = node.type || null;
+    return type &&
+        (this._reflectModuleFromTypeParam(type) || this._reflectModuleFromLiteralType(type));
+  }
+
+  /**
+   * Retrieve an `NgModule` identifier (T) from the specified `type`, if it is of the form:
+   * `ModuleWithProviders<T>`
+   * @param type The type to reflect on.
+   * @returns the identifier of the NgModule type if found, or null otherwise.
+   */
+  private _reflectModuleFromTypeParam(type: ts.TypeNode): ts.Expression|null {
     // Examine the type of the function to see if it's a ModuleWithProviders reference.
-    if (type === undefined || !ts.isTypeReferenceNode(type) || !ts.isIdentifier(type.typeName)) {
+    if (!ts.isTypeReferenceNode(type) || !ts.isIdentifier(type.typeName)) {
       return null;
     }
 
@@ -226,6 +237,32 @@ export class NgModuleDecoratorHandler implements DecoratorHandler<NgModuleAnalys
     return typeNodeToValueExpr(arg);
   }
 
+  /**
+   * Retrieve an `NgModule` identifier (T) from the specified `type`, if it is of the form:
+   * `A|B|{ngModule: T}|C`.
+   * @param type The type to reflect on.
+   * @returns the identifier of the NgModule type if found, or null otherwise.
+   */
+  private _reflectModuleFromLiteralType(type: ts.TypeNode): ts.Expression|null {
+    if (!ts.isIntersectionTypeNode(type)) {
+      return null;
+    }
+    for (const t of type.types) {
+      if (ts.isTypeLiteralNode(t)) {
+        for (const m of t.members) {
+          const ngModuleType = ts.isPropertySignature(m) && ts.isIdentifier(m.name) &&
+                  m.name.text === 'ngModule' && m.type ||
+              null;
+          const ngModuleExpression = ngModuleType && typeNodeToValueExpr(ngModuleType);
+          if (ngModuleExpression) {
+            return ngModuleExpression;
+          }
+        }
+      }
+    }
+    return null;
+  }
+
   /**
    * Compute a list of `Reference`s from a resolved metadata value.
    */