Resolve the executable path on Mac OS when sym-linked

Don't try to test sym-linked files on Windows as Junctions only support
directories.

This helps to locate the Dart SDK (if any) from the path of the dart
executable. On Linux the use of /proc/self/exe already takes care of this.

[email protected]
BUG=

Review URL: https://codereview.chromium.org//1178643007.

Author: sgjesse

runtime/bin/platform_win.cc

@@ -5,6 +5,7 @@
 #include "platform/globals.h"
 #if defined(TARGET_OS_WINDOWS)
 
+#include "bin/file.h"
 #include "bin/platform.h"
 #include "bin/log.h"
 #include "bin/socket.h"
@@ -97,7 +98,10 @@ char* Platform::ResolveExecutablePath() {
   }
   char* path = StringUtils::WideToUtf8(tmp_buffer);
   free(tmp_buffer);
-  return path;
+  // Return the canonical path as the returned path might contain symlinks.
+  char* canon_path = File::GetCanonicalPath(path);
+  free(path);
+  return canon_path;
 }
 
 }  // namespace bin

tests/standalone/io/platform_executable_test.dart

@@ -44,30 +44,27 @@ void testDartExecShouldNotBeInCurrentDir() {
 }
 
 void testShouldSucceedWithEmptyPathEnvironment() {
-  var command = Platform.isWindows ? 'dir' : 'ls';
+  var command = Platform.isWindows ? 'cmd' : 'ls';
   Process.runSync(command, [],
                   includeParentEnvironment: false,
                   environment: {_SCRIPT_KEY: 'yes', 'PATH': ''});
 }
 
 void testShouldSucceedWithSourcePlatformExecutable() {
-  //print('*** Running normally');
   verify(Platform.executable);
 }
 
 void testExeSymLinked(Directory dir) {
   var dirUri = new Uri.directory(dir.path);
   var link = new Link.fromUri(dirUri.resolve('dart_exe_link'));
   link.createSync(Platform.executable);
-  //print('*** Creating a sym-link to the executable');
   verify(link.path);
 }
 
 void testPathToDirWithExeSymLinked(Directory dir) {
   var dirUri = new Uri.directory(dir.path);
   var link = new Link.fromUri(dirUri.resolve('dart_exe_link'));
   link.createSync(Platform.executable);
-  //print('*** Path to a directory that contains a sym-link to dart bin');
   verify('dart_exe_link', altPath: dir.path);
 }
 
@@ -85,7 +82,6 @@ void testExeDirSymLinked(Directory dir) {
   var linkedBin =
       new Uri.directory(linkDirUri.toFilePath()).resolve(platformExeName);
 
-  //print('*** Running in a sym-linked directory');
   verify(linkedBin.toFilePath());
 }
 
@@ -99,15 +95,13 @@ void testPathPointsToSymLinkedSDKPath(Directory dir) {
 
   link.createSync(exeFile.parent.path);
 
-  //print('*** Path points to a sym-linked SDK dir');
   verify(platformExeName, altPath: link.path);
 }
 
 void testPathToSDKDir() {
   var exeFile = new File(Platform.executable);
   var binDirPath = exeFile.parent.path;
 
-  //print('*** Running with PATH env set to environment - fixed in 16994 - thanks!');
   verify(platformExeName, altPath: binDirPath);
 }
 
@@ -135,10 +129,16 @@ void main() {
 
   testDartExecShouldNotBeInCurrentDir();
   testShouldSucceedWithSourcePlatformExecutable(); /// 00: ok
-  withTempDir(testExeSymLinked); /// 01: ok
+  // dart:io does not support linking to files in Windows.
+  if (!Platform.isWindows) {
+    withTempDir(testExeSymLinked); /// 01: ok
+  }
   withTempDir(testExeDirSymLinked); /// 02: ok
   testPathToSDKDir(); /// 03: ok
   withTempDir(testPathPointsToSymLinkedSDKPath); /// 04: ok
-  withTempDir(testPathToDirWithExeSymLinked); /// 05: ok
+  // dart:io does not support linking to files in Windows.
+  if (!Platform.isWindows) {
+    withTempDir(testPathToDirWithExeSymLinked); /// 05: ok
+  }
   testShouldSucceedWithEmptyPathEnvironment(); /// 06: ok
 }

tests/standalone/standalone.status

@@ -17,13 +17,6 @@ javascript_compatibility_errors_test/none: Fail, OK  # Not possible to exclude o
 package/package_isolate_test: Fail # Issue 12474
 io/observatory_test: Fail
 
-[ $runtime == vm && $system == windows ]
-io/platform_executable_test/01: RuntimeError # Issue 16994
-io/platform_executable_test/02: RuntimeError # Issue 16994
-io/platform_executable_test/04: RuntimeError # Issue 16994
-io/platform_executable_test/05: RuntimeError # Issue 16994
-io/platform_executable_test/06: RuntimeError # NEEDS TRIAGE (kevmoo)
-
 [ $runtime == vm && $checked ]
 # These tests have type errors on purpose.
 io/process_invalid_arguments_test: Fail, OK