Expose PhantomJS's remote debugger URL.

lib/src/runner/browser/phantom_js.dart

 // Copyright (c) 2015, 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.
 
 library test.runner.browser.phantom_js;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
@@ skipping 21 matching lines @@
   if (status !== "success") phantom.exit(1);
 });
 """;
 
 /// A class for running an instance of PhantomJS.
 ///
 /// Any errors starting or running the process are reported through [onExit].
 class PhantomJS extends Browser {
   final name = "PhantomJS";
 
-  PhantomJS(url, {String executable})
-      : super(() => _startBrowser(url, executable));
+  final Future<Uri> remoteDebuggerUrl;
 
-  /// Starts a new instance of PhantomJS open to the given [url], which may be a
-  /// [Uri] or a [String].
-  ///
-  /// If [executable] is passed, it's used as the PhantomJS executable.
-  /// Otherwise the default executable name for the current OS will be used.
-  static Future<Process> _startBrowser(url, [String executable]) async {
-    if (executable == null) {
-      executable = Platform.isWindows ? "phantomjs.exe" : "phantomjs";
-    }
+  factory PhantomJS(url, {String executable, bool debug: false}) {
+    var remoteDebuggerCompleter = new Completer.sync();
+    return new PhantomJS._(() async {
+      if (executable == null) {
+        executable = Platform.isWindows ? "phantomjs.exe" : "phantomjs";
+      }
 
-    var dir = createTempDir();
-    var script = p.join(dir, "script.js");
-    new File(script).writeAsStringSync(_script);
+      var dir = createTempDir();
+      var script = p.join(dir, "script.js");
+      new File(script).writeAsStringSync(_script);
 
-    var process = await Process.start(
-        executable, [script, url.toString()]);
+      var port = debug ? await getUnsafeUnusedPort() : null;
 
-    // PhantomJS synchronously emits standard output, which means that if we
-    // don't drain its stdout stream it can deadlock.
-    process.stdout.listen((_) {});
+      var args = [];
+      if (debug) {
+        args.addAll([
+          "--remote-debugger-port=$port",
+          "--remote-debugger-autorun=yes"
+        ]);
+      }
+      args.addAll([script, url.toString()]);
+      var process = await Process.start(executable, args);
 
-    process.exitCode.then((exitCode) {
-      new Directory(dir).deleteSync(recursive: true);
+      // PhantomJS synchronously emits standard output, which means that if we
+      // don't drain its stdout stream it can deadlock.
+      process.stdout.listen((_) {});
 
-      if (exitCode == exit_codes.protocol) {
-        throw new ApplicationException(
-            "Only PhantomJS version 2.0.0 or greater is supported");
+      process.exitCode.then((exitCode) {
+        new Directory(dir).deleteSync(recursive: true);
+
+        if (exitCode == exit_codes.protocol) {
+          throw new ApplicationException(
+              "Only PhantomJS version 2.0.0 or greater is supported");
+        }
+      });
+
+      if (port != null) {
+        remoteDebuggerCompleter.complete(Uri.parse(
+            "http://localhost:$port/webkit/inspector/inspector.html?page=2"));
+      } else {
+        remoteDebuggerCompleter.complete(null);
       }
-    });
 
-    return process;
+      return process;
+    }, remoteDebuggerCompleter.future);
   }
+
+  PhantomJS._(Future<Process> startBrowser(), this.remoteDebuggerUrl)
+      : super(startBrowser);
 }