Fix code_transformers to consider dart symlinks (typical in brew installations)

Review URL: https://codereview.chromium.org//795433002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/code_transformers@42275 260f80e4-7a28-3924-810f-c04153c831b5

Author: sigmundch

CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.2.3+2
+
+* Added logic to discover the location of the dart SDK when the dart binary is a
+  symlink.
+
 ## 0.2.3
 
 * Added support for logging stable error messages from transformers.

lib/src/dart_sdk.dart

@@ -5,7 +5,7 @@
 library code_transformers.src.dart_sdk;
 
 import 'dart:convert' as convert;
-import 'dart:io' show File, Platform, Process;
+import 'dart:io' show File, Link, Platform, Process;
 import 'package:path/path.dart' as path;
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_io.dart';
@@ -23,18 +23,24 @@ String get dartSdkDirectory {
 
   bool isSdkDir(String dirname) =>
       new File(path.join(dirname, 'lib', '_internal', 'libraries.dart'))
-        .existsSync();
+      .existsSync();
 
-  if (path.split(Platform.executable).length == 1) {
+  String executable = Platform.executable;
+  if (path.split(executable).length == 1) {
     // TODO(blois): make this cross-platform.
     // HACK: A single part, hope it's on the path.
-    var result = Process.runSync('which', ['dart'],
-        stdoutEncoding: convert.UTF8);
-
-    var sdkDir = path.dirname(path.dirname(result.stdout));
+    executable = Process.runSync('which', ['dart'],
+        stdoutEncoding: convert.UTF8).stdout.trim();
+    // In case Dart is symlinked (e.g. homebrew on Mac) follow symbolic links.
+    var link = new Link(executable);
+    if (link.existsSync()) {
+      executable = link.resolveSymbolicLinksSync();
+    }
+    var sdkDir = path.dirname(path.dirname(executable));
     if (isSdkDir(sdkDir)) return sdkDir;
   }
-  var dartDir = path.dirname(path.absolute(Platform.executable));
+
+  var dartDir = path.dirname(path.absolute(executable));
   // If there's a sub-dir named dart-sdk then we're most likely executing from
   // a dart enlistment build directory.
   if (isSdkDir(path.join(dartDir, 'dart-sdk'))) {

pubspec.yaml

@@ -1,5 +1,5 @@
 name: code_transformers
-version: 0.2.3+1
+version: 0.2.3+2
 author: "Dart Team <[email protected]>"
 description: Collection of utilities related to creating barback transformers.
 homepage: http://www.dartlang.org