Get rid of unneeded Future.immediate() calls.

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 io;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
 import 'dart:json';
 import 'dart:uri';
 
 import '../../pkg/path/lib/path.dart' as path;
 import 'log.dart' as log;
 import 'utils.dart';
 
-bool _isGitInstalledCache;
-
-/// The cached Git command.
-String _gitCommandCache;
-
 final NEWLINE_PATTERN = new RegExp("\r\n?|\n\r?");
 
 /// Joins a number of path string parts into a single path. Handles
 /// platform-specific path separators. Parts can be [String], [Directory], or
 /// [File] objects.
 String join(part1, [part2, part3, part4, part5, part6, part7, part8]) {
   var parts = [part1, part2, part3, part4, part5, part6, part7, part8]
       .mappedBy((part) => part == null ? null : _getPath(part)).toList();
 
   return path.join(parts[0], parts[1], parts[2], parts[3], parts[4], parts[5],
@@ skipping 144 matching lines @@
 /// exist, creates them. Returns a [Future] that completes once all the
 /// directories are created.
 Future<Directory> ensureDir(path) {
   path = _getPath(path);
   log.fine("Ensuring directory $path exists.");
   if (path == '.') return new Future.immediate(new Directory('.'));
 
   return dirExists(path).then((exists) {
     if (exists) {
       log.fine("Directory $path already exists.");
-      return new Future.immediate(new Directory(path));
+      return new Directory(path);
     }
 
     return ensureDir(dirname(path)).then((_) {
       return createDir(path).catchError((asyncError) {
         if (asyncError.error is! DirectoryIOException) throw asyncError;
         // Error 17 means the directory already exists (or 183 on Windows).
         if (asyncError.error.osError.errorCode == 17 ||
             asyncError.error.osError.errorCode == 183) {
           log.fine("Got 'already exists' error when creating directory.");
           return _getDirectory(path);
@@ skipping 206 matching lines @@
     if (exists) return createSymlink(from, to);
 
     // It's OK for the self link (i.e. the root package) to not have a lib
     // directory since it may just be a leaf application that only has
     // code in bin or web.
     if (!isSelfLink) {
       log.warning('Warning: Package "$name" does not have a "lib" directory so '
                   'you will not be able to import any libraries from it.');
     }
 
-    return new Future.immediate(to);
+    return to;
   });
 }
 
 /// Given [entry] which may be a [String], [File], or [Directory] relative to
 /// the current working directory, returns its full canonicalized path.
 String getFullPath(entry) => path.absolute(_getPath(entry));
 
 /// Returns whether or not [entry] is an absolute path.
 bool isAbsolute(entry) => path.isAbsolute(_getPath(entry));
 
@@ skipping 339 matching lines @@
   var tempDir;
   return createTempDir().then((dir) {
     tempDir = dir;
     return fn(tempDir.path);
   }).whenComplete(() {
     log.fine('Cleaning up temp directory ${tempDir.path}.');
     return deleteDir(tempDir);
   });
 }
 
-/// Tests whether or not the git command-line app is available for use.
-Future<bool> get isGitInstalled {
-  if (_isGitInstalledCache != null) {
-    // TODO(rnystrom): The sleep is to pump the message queue. Can use
-    // Future.immediate() when #3356 is fixed.
-    return sleep(0).then((_) => _isGitInstalledCache);
-  }
-
-  return _gitCommand.then((git) => git != null);
-}
-
-/// Run a git process with [args] from [workingDir].
-Future<PubProcessResult> runGit(List<String> args,
-    {String workingDir, Map<String, String> environment}) {
-  return _gitCommand.then((git) => runProcess(git, args,
-        workingDir: workingDir, environment: environment));
-}
-
-/// Returns the name of the git command-line app, or null if Git could not be
-/// found on the user's PATH.
-Future<String> get _gitCommand {
-  // TODO(nweiz): Just use Future.immediate once issue 3356 is fixed.
-  if (_gitCommandCache != null) {
-    return sleep(0).then((_) => _gitCommandCache);
-  }
-
-  return _tryGitCommand("git").then((success) {
-    if (success) return new Future.immediate("git");
-
-    // Git is sometimes installed on Windows as `git.cmd`
-    return _tryGitCommand("git.cmd").then((success) {
-      if (success) return "git.cmd";
-      return null;
-    });
-  }).then((command) {
-    _gitCommandCache = command;
-    return command;
-  });
-}
-
-/// Checks whether [command] is the Git command for this computer.
-Future<bool> _tryGitCommand(String command) {
-  var completer = new Completer<bool>();
-
-  // If "git --version" prints something familiar, git is working.
-  var future = runProcess(command, ["--version"]);
-
-  future.then((results) {
-    var regex = new RegExp("^git version");
-    completer.complete(results.stdout.length == 1 &&
-                       regex.hasMatch(results.stdout[0]));
-  }).catchError((err) {
-    // If the process failed, they probably don't have it.
-    completer.complete(false);
-  });
-
-  return completer.future;
-}
-
 /// Extracts a `.tar.gz` file from [stream] to [destination], which can be a
 /// directory or a path. Returns whether or not the extraction was successful.
 Future<bool> extractTarGz(InputStream stream, destination) {
   destination = _getPath(destination);
 
   log.fine("Extracting .tar.gz stream to $destination.");
 
   if (Platform.operatingSystem == "windows") {
     return _extractTarGzWindows(stream, destination);
   }
@@ skipping 187 matching lines @@
 Directory _getDirectory(entry) {
   if (entry is Directory) return entry;
   return new Directory(entry);
 }
 
 /// Gets a [Uri] for [uri], which can either already be one, or be a [String].
 Uri _getUri(uri) {
   if (uri is Uri) return uri;
   return new Uri.fromString(uri);
 }