feat(ngcc): support for new APF where module points to esm2015 output (#36944)

As of version 10, libraries following the APF will no longer contain
ESM5 output. Hence, tests in ngcc need to be updated as they currently
rely on the release output of `@angular/core`.

Additionally, we'd need to support in ngcc that the `module`
property of entry-points no longer necessarily refers to
`esm5` output, but instead can also target `esm2015`.

We currently achieve this by checking the path the `module`
property points to. We can do this because as per APF, the
folder name is known for the esm2015 output. Long-term for
more coverage, we want to sniff the format by looking for
known ES2015 constructs in the file `module` refers to.

PR Close #36944

packages/compiler-cli/ngcc/src/command_line_options.ts

@@ -27,7 +27,7 @@ export function parseCommandLineOptions(args: string[]): NgccOptions {
             alias: 'properties',
             array: true,
             describe:
-                'An array of names of properties in package.json to compile (e.g. `module` or `es2015`)\n' +
+                'An array of names of properties in package.json to compile (e.g. `module` or `main`)\n' +
                 'Each of these properties should hold the path to a bundle-format.\n' +
                 'If provided, only the specified properties are considered for processing.\n' +
                 'If not provided, all the supported format properties (e.g. fesm2015, fesm5, es2015, esm2015, esm5, main, module) in the package.json are considered.'
@@ -136,4 +136,4 @@ export function parseCommandLineOptions(args: string[]): NgccOptions {
     errorOnFailedEntryPoint,
     tsConfigPath
   };
-}
+}

packages/compiler-cli/ngcc/src/packages/entry_point.ts

@@ -207,6 +207,15 @@ export function getEntryPointFormat(
       }
       return sniffModuleFormat(fs, join(entryPoint.path, mainFile));
     case 'module':
+      const moduleFilePath = entryPoint.packageJson['module'];
+      // As of version 10, the `module` property in `package.json` should point to
+      // the ESM2015 format output as per Angular Package format specification. This
+      // means that the `module` property captures multiple formats, as old libraries
+      // built with the old APF can still be processed. We detect the format by checking
+      // the paths that should be used as per APF specification.
+      if (typeof moduleFilePath === 'string' && moduleFilePath.includes('esm2015')) {
+        return `esm2015`;
+      }
       return 'esm5';
     default:
       return undefined;