Test against real-world Sass frameworks

In a future commit, I'll update these jobs to only run just before
release, since they're expected to be substantially less likely to
fail and we don't want to waste cycles. For now, I have them runnning
always to verify that they run successfully at least once.

.github/workflows/ci.yml

@@ -142,6 +142,68 @@ jobs:
           --errors ambiguous-doc-reference,broken-link,deprecated
           --errors unknown-directive,unknown-macro,unresolved-doc-reference
 
+  bootstrap:
+    name: "Bootstrap ${{ matrix.bootstrap_version }}"
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        bootstrap_version: [4, 5]
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dart-lang/setup-dart@v1
+      - run: dart pub get
+      - run: dart pub run grinder fetch-bootstrap${{matrix.bootstrap_version}}
+      - name: Build
+        run: dart bin/sass.dart --quiet build/bootstrap/scss:build/bootstrap-output
+        env: {GITHUB_BEARER_TOKEN: "${{ secrets.GITHUB_TOKEN }}"}
+
+  bourbon:
+    name: Bourbon
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dart-lang/setup-dart@v1
+      - run: dart pub get
+      - run: dart pub run grinder fetch-bourbon
+      - name: Test
+        run: |
+          dart bin/sass.dart --quiet -I build/bourbon -I build/bourbon/spec/fixtures \
+              build/bourbon/spec/fixtures:build/bourbon-output
+        env: {GITHUB_BEARER_TOKEN: "${{ secrets.GITHUB_TOKEN }}"}
+
+  foundation:
+    name: Foundation
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dart-lang/setup-dart@v1
+      - run: dart pub get
+      - run: dart pub run grinder fetch-foundation
+      # TODO(nweiz): Foundation has proper Sass tests, but they're currently not
+      # compatible with Dart Sass. Once they are, we should run those rather
+      # than just building the CSS output.
+      - name: Build
+        run: dart bin/sass.dart --quiet build/foundation-sites/assets:build/foundation-output
+        env: {GITHUB_BEARER_TOKEN: "${{ secrets.GITHUB_TOKEN }}"}
+
+  bulma:
+    name: Bulma
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dart-lang/setup-dart@v1
+      - run: dart pub get
+      - run: dart pub run grinder fetch-bulma
+      - name: Build
+        run: dart bin/sass.dart --quiet build/bulma/bulma.sass build/bulma-output.css
+        env: {GITHUB_BEARER_TOKEN: "${{ secrets.GITHUB_TOKEN }}"}
+
   sanity_checks:
     name: Sanity checks
     runs-on: ubuntu-latest

pubspec.yaml

@@ -34,7 +34,7 @@ dependencies:
 dev_dependencies:
   analyzer: ^2.2.0
   archive: ^3.1.2
-  cli_pkg: ^1.3.0
+  cli_pkg: ^1.7.0
   crypto: ^3.0.0
   dart_style: ^2.0.0
   grinder: ^0.9.0

tool/grind.dart

@@ -15,6 +15,7 @@ import 'grind/synchronize.dart';
 
 export 'grind/bazel.dart';
 export 'grind/benchmark.dart';
+export 'grind/frameworks.dart';
 export 'grind/sanity_check.dart';
 export 'grind/subpackages.dart';
 export 'grind/synchronize.dart';
@@ -34,8 +35,8 @@ void main(List<String> args) {
           as Map<String, dynamic>;
   pkg.npmReadme.fn = () => _readAndResolveMarkdown("package/README.npm.md");
   pkg.standaloneName.value = "dart-sass";
-  pkg.githubUser.fn = () => Platform.environment["GH_USER"]!;
-  pkg.githubPassword.fn = () => Platform.environment["GH_TOKEN"]!;
+  pkg.githubUser.fn = () => Platform.environment["GH_USER"];
+  pkg.githubPassword.fn = () => Platform.environment["GH_TOKEN"];
 
   pkg.githubReleaseNotes.fn = () =>
       "To install Sass ${pkg.version}, download one of the packages below "

tool/grind/frameworks.dart

@@ -0,0 +1,71 @@
+// Copyright 2021 Google Inc. Use of this source code is governed by an
+// MIT-style license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+import 'dart:convert';
+
+import 'package:grinder/grinder.dart';
+import 'package:http/http.dart' as http;
+
+import 'utils.dart';
+
+@Task('Download Bootstrap 5.x for testing purposes.')
+Future<void> fetchBootstrap5() => _getLatestRelease('twbs/bootstrap');
+
+@Task('Download Bootstrap 4.x for testing purposes.')
+Future<void> fetchBootstrap4() =>
+    _getLatestRelease('twbs/bootstrap', pattern: RegExp(r'^v4\.'));
+
+@Task('Download Bourbon for testing purposes.')
+Future<void> fetchBourbon() => _getLatestRelease('thoughtbot/bourbon');
+
+@Task('Download Foundation for testing purposes.')
+Future<void> fetchFoundation() =>
+    _getLatestRelease('foundation/foundation-sites');
+
+@Task('Download Bulma for testing purposes.')
+Future<void> fetchBulma() => _getLatestRelease('jgthms/bulma');
+
+/// Clones the latest release of the given GitHub repository [slug].
+///
+/// If [pattern] is passed, this will clone the latest release that matches that
+/// pattern.
+Future<void> _getLatestRelease(String slug, {Pattern? pattern}) async {
+  await cloneOrCheckout('git://github.com/$slug',
+      await _findLatestRelease(slug, pattern: pattern));
+}
+
+/// Returns the tag name of the latest release for the given GitHub repository
+/// [slug].
+///
+/// If [pattern] is passed, this will find the latest release that matches that
+/// pattern.
+Future<String> _findLatestRelease(String slug, {Pattern? pattern}) async {
+  var releases = await _fetchReleases(slug);
+  if (pattern == null) return releases[0]['tag_name'] as String;
+
+  var page = 1;
+  while (releases.isNotEmpty) {
+    for (var release in releases) {
+      var tagName = release['tag_name'] as String;
+      if (pattern.allMatches(tagName).isNotEmpty) return tagName;
+    }
+
+    page++;
+    releases = await _fetchReleases(slug, page: page);
+  }
+
+  fail("Couldn't find a release of $slug matching $pattern.");
+}
+
+/// Fetches the GitHub releases page for the repo at [slug].
+Future<List<Map<String, dynamic>>> _fetchReleases(String slug,
+    {int page = 1}) async {
+  var result = json.decode(await http.read(
+      Uri.parse("https://api.github.com/repos/$slug/releases?page=$page"),
+      headers: {
+        "accept": "application/vnd.github.v3+json",
+        "authorization": githubAuthorization
+      })) as List<dynamic>;
+  return result.cast<Map<String, dynamic>>();
+}

tool/grind/subpackages.dart

@@ -12,6 +12,8 @@ import 'package:path/path.dart' as p;
 import 'package:pubspec_parse/pubspec_parse.dart';
 import 'package:yaml/yaml.dart';
 
+import 'utils.dart';
+
 /// The path in which pub expects to find its credentials file.
 final String _pubCredentialsPath = () {
   // This follows the same logic as pub:
@@ -30,17 +32,6 @@ final String _pubCredentialsPath = () {
   return p.join(cacheDir, 'credentials.json');
 }();
 
-/// Returns the HTTP basic authentication Authorization header from the
-/// environment.
-String get _githubAuthorization {
-  var bearerToken = pkg.githubBearerToken.value;
-  return bearerToken != null
-      ? "Bearer $bearerToken"
-      : "Basic " +
-          base64.encode(utf8
-              .encode(pkg.githubUser.value + ':' + pkg.githubPassword.value));
-}
-
 @Task('Deploy sub-packages to pub.')
 Future<void> deploySubPackages() async {
   // Write pub credentials
@@ -86,7 +77,7 @@ Future<void> deploySubPackages() async {
         headers: {
           "accept": "application/vnd.github.v3+json",
           "content-type": "application/json",
-          "authorization": _githubAuthorization
+          "authorization": githubAuthorization
         },
         body: jsonEncode({
           "ref": "refs/tags/${pubspec.name}/${pubspec.version}",

tool/grind/utils.dart

@@ -3,6 +3,7 @@
 // https://opensource.org/licenses/MIT.
 
 import 'dart:async';
+import 'dart:convert';
 import 'dart:io';
 
 import 'package:cli_pkg/cli_pkg.dart' as pkg;
@@ -17,6 +18,17 @@ final sassBotEnvironment = RunOptions(environment: {
   "GIT_COMMITTER_EMAIL": pkg.botEmail.value
 });
 
+/// Returns the HTTP basic authentication Authorization header from the
+/// environment.
+String get githubAuthorization {
+  var bearerToken = pkg.githubBearerToken.value;
+  return bearerToken != null
+      ? "Bearer $bearerToken"
+      : "Basic " +
+          base64.encode(utf8
+              .encode(pkg.githubUser.value + ':' + pkg.githubPassword.value));
+}
+
 /// Ensure that the `build/` directory exists.
 void ensureBuild() {
   Directory('build').createSync(recursive: true);
@@ -47,18 +59,22 @@ Future<String> cloneOrCheckout(String url, String ref) async {
 
   var path = p.join("build", name);
 
-  if (Directory(p.join(path, '.git')).existsSync()) {
-    log("Updating $url");
-    await runAsync("git",
-        arguments: ["fetch", "origin"], workingDirectory: path);
-  } else {
+  if (!Directory(p.join(path, '.git')).existsSync()) {
     delete(Directory(path));
-    await runAsync("git", arguments: ["clone", url, path]);
+    await runAsync("git", arguments: ["init", path]);
     await runAsync("git",
         arguments: ["config", "advice.detachedHead", "false"],
         workingDirectory: path);
+    await runAsync("git",
+        arguments: ["remote", "add", "origin", url], workingDirectory: path);
+  } else {
+    log("Updating $url");
   }
-  await runAsync("git", arguments: ["checkout", ref], workingDirectory: path);
+
+  await runAsync("git",
+      arguments: ["fetch", "origin", "--depth=1", ref], workingDirectory: path);
+  await runAsync("git",
+      arguments: ["checkout", "FETCH_HEAD"], workingDirectory: path);
   log("");
 
   return path;