fix(@angular-devkit/build-angular): ensure webpack tilde resolve behavior for stylesheet resources

Author: clydin

packages/angular_devkit/build_angular/src/angular-cli-files/plugins/postcss-cli-resources.ts

@@ -81,11 +81,7 @@ export default postcss.plugin('postcss-cli-resources', (options: PostcssCliResou
       return cachedUrl;
     }
 
-    if (inputUrl.startsWith('~')) {
-      inputUrl = inputUrl.substr(1);
-    }
-
-    if (inputUrl.startsWith('/')) {
+    if (rebaseRootRelative && inputUrl.startsWith('/')) {
       let outputUrl = '';
       if (deployUrl.match(/:\/\//) || deployUrl.startsWith('/')) {
         // If deployUrl is absolute or root relative, ignore baseHref & use deployUrl as is.
@@ -103,6 +99,10 @@ export default postcss.plugin('postcss-cli-resources', (options: PostcssCliResou
       return outputUrl;
     }
 
+    if (inputUrl.startsWith('~')) {
+      inputUrl = inputUrl.substr(1);
+    }
+
     const { pathname, hash, search } = url.parse(inputUrl.replace(/\\/g, '/'));
     const resolver = (file: string, base: string) => new Promise<string>((resolve, reject) => {
       loader.resolve(base, decodeURI(file), (err, result) => {

packages/angular_devkit/build_angular/test/browser/styles_spec_large.ts

@@ -257,6 +257,17 @@ describe('Browser Builder styles', () => {
   });
 
   it(`supports font-awesome imports`, async () => {
+    host.writeMultipleFiles({
+      'src/styles.scss': `
+        @import "font-awesome/scss/font-awesome";
+      `,
+    });
+
+    const overrides = { extractCss: true, styles: [`src/styles.scss`] };
+    await browserBuild(architect, host, target, overrides);
+  }, 30000);
+
+  it(`supports font-awesome imports (tilde)`, async () => {
     host.writeMultipleFiles({
       'src/styles.scss': `
         $fa-font-path: "~font-awesome/fonts";
@@ -578,6 +589,31 @@ describe('Browser Builder styles', () => {
     await browserBuild(architect, host, target, overrides);
   });
 
+  it('causes equal failure for tilde and tilde-slash url()', async () => {
+    host.writeMultipleFiles({
+      'src/styles.css': `
+        body {
+          background-image: url('~/does-not-exist.jpg');
+        }
+      `,
+    });
+
+    const overrides = { extractCss: true, optimization: true };
+    const run = await architect.scheduleTarget(target, overrides);
+    await expectAsync(run.result).toBeResolvedTo(jasmine.objectContaining({ success: false }));
+
+    host.writeMultipleFiles({
+      'src/styles.css': `
+        body {
+          background-image: url('~does-not-exist.jpg');
+        }
+      `,
+    });
+
+    const run2 = await architect.scheduleTarget(target, overrides);
+    await expectAsync(run2.result).toBeResolvedTo(jasmine.objectContaining({ success: false }));
+  });
+
   it('supports Protocol-relative Url', async () => {
     host.writeMultipleFiles({
       'src/styles.css': `