Add a Pub source that checks packages out from Git.

utils/pub/io.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Helper functionality to make working with IO easier.
  */
 #library('pub_io');
 
 #import('dart:io');
@@ skipping 240 matching lines @@
  * Given [entry] which may be a [String], [File], or [Directory] relative to
  * the current working directory, returns its full canonicalized path.
  */
 // TODO(rnystrom): Should this be async?
 String getFullPath(entry) => new File(_getPath(entry)).fullPathSync();
 
 /**
  * Spawns and runs the process located at [executable], passing in [args].
  * Returns a [Future] that will complete the results of the process after it
  * has ended.
+ *
+ * If [pipeStdout] and/or [pipeStderr] are set, all output from the subprocess's
+ * output streams are sent to the parent process's output streams. Output from
+ * piped streams won't be available in the result object.
  */
 Future<PubProcessResult> runProcess(String executable, List<String> args,
-    [String workingDir]) {
+    [String workingDir, bool pipeStdout = false, bool pipeStderr = false]) {
   int exitCode;
 
   final options = new ProcessOptions();
   if (workingDir != null) options.workingDirectory = workingDir;
 
   final process = Process.start(executable, args, options);
 
   final outStream = new StringInputStream(process.stdout);
   final processStdout = <String>[];
 
   final errStream = new StringInputStream(process.stderr);
   final processStderr = <String>[];
 
   final completer = new Completer<PubProcessResult>();
 
   checkComplete() {
     // Wait until the process is done and its output streams are closed.
-    if (!outStream.closed) return;
-    if (!errStream.closed) return;
+    if (!pipeStdout && !outStream.closed) return;
+    if (!pipeStderr && !errStream.closed) return;
     if (exitCode == null) return;
 
     completer.complete(new PubProcessResult(
         processStdout, processStderr, exitCode));
   }
 
-  outStream.onLine   = () => processStdout.add(outStream.readLine());
-  outStream.onClosed = checkComplete;
-  outStream.onError  = (error) => completer.completeException(error);
+  if (pipeStdout) {
+    process.stdout.pipe(stdout, close: false);
+  } else {
+    outStream.onLine   = () => processStdout.add(outStream.readLine());
+    outStream.onClosed = checkComplete;
+    outStream.onError  = (error) => completer.completeException(error);
+  }
 
-  errStream.onLine   = () => processStderr.add(errStream.readLine());
-  errStream.onClosed = checkComplete;
-  errStream.onError  = (error) => completer.completeException(error);
+  if (pipeStderr) {
+    process.stderr.pipe(stderr, close: false);
+  } else {
+    errStream.onLine   = () => processStderr.add(errStream.readLine());
+    errStream.onClosed = checkComplete;
+    errStream.onError  = (error) => completer.completeException(error);
+  }
 
   process.onExit = (actualExitCode) {
     exitCode = actualExitCode;
     checkComplete();
   };
 
   process.onError = (error) => completer.completeException(error);
 
   return completer.future;
 }
 
 /**
  * Contains the results of invoking a [Process] and waiting for it to complete.
  */
 class PubProcessResult {
   final List<String> stdout;
   final List<String> stderr;
   final int exitCode;
 
   const PubProcessResult(this.stdout, this.stderr, this.exitCode);
+
+  bool get success() => exitCode == 0;
 }
 
 /**
  * Gets the path string for [entry], which can either already be a path string,
  * or be a [File] or [Directory]. Allows working generically with "file-like"
  * objects.
  */
 String _getPath(entry) {
   if (entry is String) return entry;
   if (entry is File) return entry.name;
   if (entry is Directory) return entry.path;
   throw 'Entry $entry is not a supported type.';
 }
 
 /**
  * Gets a [Directory] for [entry], which can either already be one, or be a
  * [String].
  */
 Directory _getDirectory(entry) {
   if (entry is Directory) return entry;
   return new Directory(entry);
 }