[ffigen] Format using dart format (#2362)

Author: liamappelbe

pkgs/ffigen/CHANGELOG.md

@@ -1,5 +1,10 @@
 ## 19.1.0-wip
 
+- Format using `dart format` so that the formatter uses the target package's
+  Dart version and formatting options.
+- Add `_` to the list of Dart keywords, since it has special meaning in newer
+  Dart versions.
+
 ## 19.0.0
 
 - Use package:objective_c 8.0.0.

pkgs/ffigen/lib/src/code_generator/dart_keywords.dart

@@ -6,6 +6,7 @@
 ///
 /// Source: https://dart.dev/guides/language/language-tour#keywords.
 const keywords = {
+  '_',
   'abstract',
   'as',
   'assert',

pkgs/ffigen/lib/src/code_generator/library.dart

@@ -4,7 +4,7 @@
 
 import 'dart:io';
 
-import 'package:dart_style/dart_style.dart';
+import 'package:logging/logging.dart';
 import 'package:yaml_edit/yaml_edit.dart';
 
 import '../code_generator.dart';
@@ -13,6 +13,8 @@ import '../config_provider/config_types.dart';
 
 import 'writer.dart';
 
+final _logger = Logger('ffigen.library');
+
 /// Container for all Bindings.
 class Library {
   /// List of bindings in this library.
@@ -92,14 +94,19 @@ class Library {
   /// generated file.
   void generateFile(File file, {bool format = true}) {
     if (!file.existsSync()) file.createSync(recursive: true);
-    var bindings = generate();
+    file.writeAsStringSync(generate());
     if (format) {
-      final formatter = DartFormatter(
-        languageVersion: DartFormatter.latestShortStyleLanguageVersion,
-      );
-      bindings = formatter.format(bindings);
+      final result = Process.runSync(
+          Platform.resolvedExecutable,
+          [
+            'format',
+            file.absolute.path,
+          ],
+          workingDirectory: file.parent.absolute.path);
+      if (result.exitCode != 0) {
+        _logger.severe('Formatting failed\n${result.stdout}\n${result.stderr}');
+      }
     }
-    file.writeAsStringSync(bindings);
   }
 
   /// Generates [file] with the Objective C code needed for the bindings, if

pkgs/ffigen/test/.gitignore

@@ -0,0 +1 @@
+.temp

pkgs/ffigen/test/test_utils.dart

@@ -8,7 +8,6 @@ import 'package:ffigen/src/code_generator.dart';
 import 'package:ffigen/src/config_provider/config.dart';
 import 'package:ffigen/src/config_provider/utils.dart';
 import 'package:ffigen/src/config_provider/yaml_config.dart';
-import 'package:ffigen/src/strings.dart' as strings;
 import 'package:logging/logging.dart';
 import 'package:package_config/package_config_types.dart';
 import 'package:path/path.dart' as path;
@@ -90,6 +89,9 @@ String absPath(String p) => path.join(packagePathForTests, p);
 String configPath(String directory, String file) =>
     absPath(configPathForTest(directory, file));
 
+/// Returns the temp directory used to store bindings generated by tests.
+String tmpDir = path.join(packagePathForTests, 'test', '.temp');
+
 /// Generates actual file using library and tests using [expect] with expected.
 ///
 /// This will not delete the actual debug file incase [expect] throws an error.
@@ -102,9 +104,7 @@ void _matchFileWithExpected({
   String Function(String)? codeNormalizer,
 }) {
   final expectedPath = path.joinAll([packagePathForTests, ...pathToExpected]);
-  final file = File(
-    path.join(strings.tmpDir, pathForActual),
-  );
+  final file = File(path.join(tmpDir, pathForActual));
   fileWriter(library: library, file: file);
   try {
     final actual =