Avoid using RegExps in path to work around issue 19090.

pkg/path/lib/src/style/posix.dart

Index: pkg/path/lib/src/style/posix.dart
diff --git a/pkg/path/lib/src/style/posix.dart b/pkg/path/lib/src/style/posix.dart
index e0b601743c743b829aa817fc5721e3128cadb9a9..8067fad74a4ccddb3631ae16b007061568269a13 100644
--- a/pkg/path/lib/src/style/posix.dart
+++ b/pkg/path/lib/src/style/posix.dart
@@ -13,9 +13,24 @@ class PosixStyle extends InternalStyle {
 
   final name = 'posix';
   final separator = '/';
+  final separators = const ['/'];
+
+  // Deprecated properties.
+
   final separatorPattern = new RegExp(r'/');
   final needsSeparatorPattern = new RegExp(r'[^/]$');
   final rootPattern = new RegExp(r'^/');
+  final relativeRootPattern = null;
+
+  bool needsSeparator(String path) =>
+      !path.isEmpty && path.codeUnitAt(path.length - 1) != 0x2f; // "/"

[Bob Nystrom, 2014/06/02 22:43:05]

!path.isEmpty -> path.isNotEmpty

and elsewhere.

[nweiz, 2014/06/02 23:13:25]

Done.

+
+  String getRoot(String path) {
+    if (!path.isEmpty && path.codeUnitAt(0) == 0x2f) return '/';
+    return null;
+  }
+
+  String getRelativeRoot(String path) => null;
 
   String pathFromUri(Uri uri) {
     if (uri.scheme == '' || uri.scheme == 'file') {