fix(@angular-devkit/build-angular): don't log blank warnings in console

Closes #18524

(cherry picked from commit 155707a)

Author: alan-agius4

packages/angular_devkit/build_angular/src/angular-cli-files/utilities/stats.ts

@@ -87,10 +87,11 @@ export function statsToString(json: any, statsConfig: any) {
 }
 
 // TODO(#16193): Don't emit this warning in the first place rather than just suppressing it.
-const ERRONEOUS_WARNINGS = [
+const ERRONEOUS_WARNINGS_FILTER = (warning: string) => ![
   /multiple assets emit different content.*3rdpartylicenses\.txt/i,
-];
-export function statsWarningsToString(json: any, statsConfig: any) {
+].some(msg => msg.test(warning));
+
+export function statsWarningsToString(json: any, statsConfig: any): string {
   const colors = statsConfig.colors;
   const rs = (x: string) => colors ? reset(x) : x;
   const y = (x: string) => colors ? bold(yellow(x)) : x;
@@ -104,12 +105,12 @@ export function statsWarningsToString(json: any, statsConfig: any) {
 
   return rs('\n' + warnings
     .map((warning: any) => `${warning}`)
-    .filter((warning: string) => !ERRONEOUS_WARNINGS.some((erroneous) => erroneous.test(warning)))
+    .filter(ERRONEOUS_WARNINGS_FILTER)
     .map((warning: string) => y(`WARNING in ${warning}`))
     .join('\n\n'));
 }
 
-export function statsErrorsToString(json: any, statsConfig: any) {
+export function statsErrorsToString(json: any, statsConfig: any): string {
   const colors = statsConfig.colors;
   const rs = (x: string) => colors ? reset(x) : x;
   const r = (x: string) => colors ? bold(red(x)) : x;
@@ -120,16 +121,18 @@ export function statsErrorsToString(json: any, statsConfig: any) {
       .reduce((a: string[], b: string[]) => [...a, ...b], [])
     );
   }
+
   return rs('\n' + errors
     .map((error: any) => r(`ERROR in ${error}`))
     .join('\n\n')
   );
 }
 
 export function statsHasErrors(json: any): boolean {
-  return json.errors.length > 0 || !!json.children?.some((c: any) => c.errors.length);
+  return json.errors.length || !!json.children?.some((c: any) => c.errors.length);
 }
 
 export function statsHasWarnings(json: any): boolean {
-  return json.warnings.length > 0 || !!json.children?.some((c: any) => c.warnings.length);
+  return json.warnings.filter(ERRONEOUS_WARNINGS_FILTER).length ||
+    !!json.children?.some((c: any) => c.warnings.filter(ERRONEOUS_WARNINGS_FILTER).length);
 }

packages/angular_devkit/build_angular/src/browser/index.ts

@@ -101,10 +101,10 @@ export function createBrowserLoggingCallback(
       logger.info(statsToString(json, config.stats));
     }
 
-    if (stats.hasWarnings()) {
+    if (statsHasWarnings(json)) {
       logger.warn(statsWarningsToString(json, config.stats));
     }
-    if (stats.hasErrors()) {
+    if (statsHasErrors(json)) {
       logger.error(statsErrorsToString(json, config.stats));
     }
   };

packages/angular_devkit/build_angular/src/extract-i18n/index.ts

@@ -20,7 +20,7 @@ import {
   getStatsConfig,
   getStylesConfig,
 } from '../angular-cli-files/models/webpack-configs';
-import { statsErrorsToString, statsWarningsToString } from '../angular-cli-files/utilities/stats';
+import { statsErrorsToString, statsHasErrors, statsHasWarnings, statsWarningsToString } from '../angular-cli-files/utilities/stats';
 import { Schema as BrowserBuilderOptions } from '../browser/schema';
 import { createI18nOptions } from '../utils/i18n-options';
 import { assertCompatibleAngularVersion } from '../utils/version';
@@ -127,11 +127,11 @@ export async function execute(
   const logging: WebpackLoggingCallback = (stats, config) => {
     const json = stats.toJson({ errors: true, warnings: true });
 
-    if (stats.hasWarnings()) {
+    if (statsHasWarnings(json)) {
       context.logger.warn(statsWarningsToString(json, config.stats));
     }
 
-    if (stats.hasErrors()) {
+    if (statsHasErrors(json)) {
       context.logger.error(statsErrorsToString(json, config.stats));
     }
   };