build: fix random ngc resolve failures (#807)

Equivalent to angular/components#12103

Author: CaerusKaru

tools/package-tools/build-package.ts

@@ -1,10 +1,12 @@
 import {join} from 'path';
-import {red} from 'chalk';
 import {PackageBundler} from './build-bundles';
 import {buildConfig} from './build-config';
+import {
+  addImportAsToAllMetadata,
+  compileEntryPoint,
+  renamePrivateReExportsToBeUnique,
+} from './compile-entry-point';
 import {getSecondaryEntryPointsForPackage} from './secondary-entry-points';
-import {compileEntryPoint, renamePrivateReExportsToBeUnique} from './compile-entry-point';
-import {ngcCompile} from './ngc-compile';
 
 const {packagesDir, outputDir} = buildConfig;
 
@@ -74,7 +76,8 @@ export class BuildPackage {
 
   /** Compiles the TypeScript test source files for the package. */
   async compileTests() {
-    await this._compileTestEntryPoint(testsTsconfigName);
+    return compileEntryPoint(this, testsTsconfigName)
+      .then(() => addImportAsToAllMetadata(this));
   }
 
   /** Creates all bundles for the package and all associated entry points. */
@@ -89,18 +92,6 @@ export class BuildPackage {
         .then(() => renamePrivateReExportsToBeUnique(this, p));
   }
 
-  /** Compiles the TypeScript sources of a primary or secondary entry point. */
-  private _compileTestEntryPoint(tsconfigName: string, secondaryEntryPoint = ''): Promise<any> {
-    const entryPointPath = join(this.sourceDir, secondaryEntryPoint);
-    const entryPointTsconfigPath = join(entryPointPath, tsconfigName);
-
-    return ngcCompile(['-p', entryPointTsconfigPath]).catch(() => {
-      const error = red(`Failed to compile ${secondaryEntryPoint} using ${entryPointTsconfigPath}`);
-      console.error(error);
-      return Promise.reject(error);
-    });
-  }
-
   /** Stores the secondary entry-points for this package if they haven't been computed already. */
   private cacheSecondaryEntryPoints() {
     if (!this._secondaryEntryPoints) {

tools/package-tools/compile-entry-point.ts

@@ -26,6 +26,19 @@ export async function compileEntryPoint(buildPackage: BuildPackage, tsconfigName
   });
 }
 
+/**
+ * Adds `importAs` property to all generated metadata.json files for a package's secondary
+ * entry-points. This is necessary for unit tests so that the imports generated by using the
+ * `providedIn` syntax are able to resolve symbols to the "expected" location (e.g.
+ * "@angular/cdk/overlay" instead of a local relative path). Assumes that the package has already
+ * been built.
+ */
+export function addImportAsToAllMetadata(buildPackage: BuildPackage) {
+  for (const entryPoint of buildPackage.secondaryEntryPoints) {
+    addImportAs(buildPackage.name, buildPackage.outputDir, entryPoint);
+  }
+}
+
 /** Renames `ɵa`-style re-exports generated by Angular to be unique across compilation units. */
 export function renamePrivateReExportsToBeUnique(buildPackage: BuildPackage,
                                                   secondaryEntryPoint = '') {
@@ -44,6 +57,16 @@ export function renamePrivateReExportsToBeUnique(buildPackage: BuildPackage,
   }
 }
 
+/** Adds `importAs` property to generated all metadata.json files for an entry-point. */
+function addImportAs(packageName: string, outputPath: string, secondaryEntryPoint: string): void {
+  const path = join(outputPath, secondaryEntryPoint);
+  glob(join(path, '**/*.+(metadata.json)')).forEach(metadataPath => {
+    let metadata = JSON.parse(readFileSync(metadataPath, 'utf-8'));
+    metadata[0]['importAs'] = `@angular/${packageName}/${secondaryEntryPoint}`;
+    writeFileSync(metadataPath, JSON.stringify(metadata), 'utf-8');
+  });
+}
+
 /** Updates exports in designated folder with identifier specified. */
 function addIdToGlob(outputPath: string, entryPointId: number): void {
   glob(join(outputPath, '**/*.+(js|d.ts|metadata.json)')).forEach(filePath => {

tools/package-tools/gulp/build-tasks-gulp.ts

@@ -54,8 +54,11 @@ export function createPackageBuildTasks(buildPackage: BuildPackage) {
   ));
 
   task(`${taskName}:build-no-bundles`, sequenceTask(
+    // Build assets before building the ESM output. Since we compile with NGC, the compiler
+    // tries to resolve all required assets.
+    `${taskName}:assets`,
     // Build the ESM output that includes all test files. Also build assets for the package.
-    [`${taskName}:build:esm:tests`, `${taskName}:assets`],
+    `${taskName}:build:esm:tests`,
     // Inline assets into ESM output.
     `${taskName}:assets:inline`
   ));