Add a little script to run migrated (and unmigrated) tests.

Change-Id: I1c64b96e79084d2b45d97ae7fcb6c0f0eddb6f3d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142561
Reviewed-by: Nicholas Shahan <nshahan@google.com>
Commit-Queue: Nicholas Shahan <nshahan@google.com>
Auto-Submit: Bob Nystrom <rnystrom@google.com>

tools/migration/bin/test.dart

@@ -0,0 +1,86 @@
+// Copyright (c) 2020, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/// A little utility script to make it easier to run NNBD and legacy tests.
+import 'dart:io';
+
+import 'package:args/args.dart';
+
+import 'package:migration/src/io.dart';
+import 'package:migration/src/test_directories.dart';
+
+/// Maps "normal" names for Dart implementations to their test runner compiler
+/// names.
+const compilerNames = {
+  "analyzer": "dart2analyzer",
+  "cfe": "fasta",
+  "dart2js": "dart2js",
+  "ddc": "dartdevk",
+  "vm": "dartk",
+};
+
+void main(List<String> arguments) async {
+  var testDir = "";
+  var isLegacy = false;
+  var compilers = <String>[];
+
+  var argParser = ArgParser();
+  argParser.addFlag("legacy",
+      help: "Run the legacy tests.",
+      negatable: false,
+      callback: (flag) => isLegacy = false);
+
+  argParser.addMultiOption("compiler",
+      abbr: "c",
+      help: "Which Dart implementations to run the tests on.",
+      allowed: ["analyzer", "cfe", "dart2js", "ddc", "vm"],
+      callback: (implementations) {
+    compilers.addAll(implementations.map((name) => compilerNames[name]));
+  });
+
+  if (arguments.contains("--help")) {
+    showUsage(argParser);
+  }
+
+  try {
+    var argResults = argParser.parse(arguments);
+
+    if (argResults.rest.length != 1) {
+      showUsage(argParser, "Missing test directory.");
+    }
+
+    testDir = argResults.rest[0];
+
+    // If the test directory is just a single identifier, assume it's a language
+    // test subdirectory.
+    if (!testDir.contains("/")) testDir = "language_2/$testDir";
+  } on FormatException catch (exception) {
+    showUsage(argParser, exception.message);
+  }
+
+  if (!isLegacy) testDir = toNnbdPath(testDir);
+
+  var testArgs = [
+    "--mode=release",
+    if (!isLegacy) ...[
+      "--enable-experiment=non-nullable",
+      "--nnbd=strong",
+    ],
+    "--compiler=${compilers.join(',')}",
+    testDir,
+  ];
+
+  print("Running tools/test.py ${testArgs.join(' ')}");
+  await runProcessAsync("tools/test.py", testArgs);
+}
+
+void showUsage(ArgParser argParser, [String error]) {
+  if (error != null) {
+    print(error);
+    print("");
+  }
+  print("Usage: dart test.dart <source dir>");
+  print(argParser.usage);
+  exit(error == null ? 0 : 1);
+}

tools/migration/lib/src/io.dart

@@ -131,6 +131,20 @@ bool runProcess(String executable, List<String> arguments,
   return result.exitCode == 0;
 }
 
+Future<bool> runProcessAsync(String executable, List<String> arguments,
+    {String workingDirectory}) async {
+  if (dryRun) {
+    print("Dry run: run $executable ${arguments.join(' ')}");
+    return true;
+  }
+
+  var process = await Process.start(executable, arguments);
+  process.stdout.listen(stdout.add);
+  process.stderr.listen(stderr.add);
+
+  return (await process.exitCode) == 0;
+}
+
 /// Returns a list of the paths to all files within [dir], which is
 /// assumed to be relative to the SDK's "tests" directory and having file with
 /// an extension in [extensions].