From 13cd62a6f00c6c7b659c15e2462d43513b4b531d Mon Sep 17 00:00:00 2001
From: Tobe O <thosakwe@gmail.com>
Date: Mon, 9 Oct 2017 09:39:14 -0400
Subject: [PATCH] Perf update

---
 lib/src/router.dart  | 11 ++++++-----
 lib/string_util.dart | 43 +++++++++++++++++++++++++++++++++++++++++
 pubspec.yaml         |  2 +-
 test/strip_test.dart | 46 ++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 96 insertions(+), 6 deletions(-)
 create mode 100644 lib/string_util.dart
 create mode 100644 test/strip_test.dart

diff --git a/lib/src/router.dart b/lib/src/router.dart
index bafbbae5..dfa1e42a 100644
--- a/lib/src/router.dart
+++ b/lib/src/router.dart
@@ -2,6 +2,7 @@ library angel_route.src.router;
 
 import 'extensible.dart';
 import 'routing_exception.dart';
+import '../string_util.dart';
 part 'symlink_route.dart';
 part 'route.dart';
 part 'routing_result.dart';
@@ -266,8 +267,8 @@ class Router {
   /// with the given method.
   RoutingResult resolve(String absolute, String relative,
       {String method: 'GET'}) {
-    final cleanAbsolute = absolute.replaceAll(_straySlashes, '');
-    final cleanRelative = relative.replaceAll(_straySlashes, '');
+    final cleanAbsolute = stripStraySlashes(absolute);
+    final cleanRelative = stripStraySlashes(relative);
     final segments = cleanRelative.split('/').where((str) => str.isNotEmpty);
     //print(
     //   'Now resolving $method "/$cleanRelative", absolute: $cleanAbsolute');
@@ -283,9 +284,9 @@ class Router {
 
           if (match != null) {
             final cleaned = s.join('/').replaceFirst(match[0], '');
-            final tail = cleanRelative
-                .replaceAll(route._head, '')
-                .replaceAll(_straySlashes, '');
+            var tail = cleanRelative
+                .replaceAll(route._head, '');
+            tail = stripStraySlashes(tail);
 
             if (cleaned.isEmpty) {
               //print(
diff --git a/lib/string_util.dart b/lib/string_util.dart
new file mode 100644
index 00000000..9a9e5bf7
--- /dev/null
+++ b/lib/string_util.dart
@@ -0,0 +1,43 @@
+/// Helper functions to performantly transform strings, without `RegExp`.
+library angel_route.string_util;
+
+/// Removes leading and trailing occurrences of a pattern from a string.
+String stripStray(String haystack, String needle) {
+  int firstSlash;
+
+  if (haystack.startsWith(needle)) {
+    firstSlash = haystack.indexOf(needle);
+    if (firstSlash == -1) return haystack;
+  } else {
+    firstSlash = -1;
+  }
+
+  if (firstSlash == haystack.length - 1)
+    return haystack.length == 1 ? '' : haystack.substring(0, firstSlash);
+
+  // Find last leading index of slash
+  for (int i = firstSlash + 1; i < haystack.length; i++) {
+    if (haystack[i] != needle) {
+      var sub = haystack.substring(i);
+
+      if (!sub.endsWith(needle))
+        return sub;
+
+      var lastSlash = sub.lastIndexOf(needle);
+
+      for (int j = lastSlash - 1; j >= 0; j--) {
+        if (sub[j] != needle) {
+          return sub.substring(0, j + 1);
+        }
+      }
+
+      return lastSlash == -1 ? sub : sub.substring(0, lastSlash);
+    }
+  }
+
+  return haystack.substring(0, firstSlash);
+}
+
+String stripStraySlashes(String str) => stripStray(str, '/');
+
+String stripRegexStraySlashes(String str) => stripStray(str, '\\/');
diff --git a/pubspec.yaml b/pubspec.yaml
index b1ed6dac..c5aceb5f 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: angel_route
 description: A powerful, isomorphic routing library for Dart.
-version: 1.0.6
+version: 1.0.7
 author: Tobe O <thosakwe@gmail.com>
 homepage: https://github.com/angel-dart/angel_route
 dev_dependencies:
diff --git a/test/strip_test.dart b/test/strip_test.dart
new file mode 100644
index 00000000..955f1bf5
--- /dev/null
+++ b/test/strip_test.dart
@@ -0,0 +1,46 @@
+import 'package:angel_route/string_util.dart';
+import 'package:test/test.dart';
+
+main() {
+  test('strip leading', () {
+    var a = '///a';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'a');
+  });
+
+  test('strip trailing', () {
+    var a = 'a///';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'a');
+  });
+
+  test('strip both', () {
+    var a = '///a///';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'a');
+  });
+
+  test('intermediate slashes preserved', () {
+    var a = '///a///b//';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'a///b');
+  });
+
+  test('only if starts with', () {
+    var a = 'd///a///b//';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'd///a///b');
+  });
+
+  test('only if ends with', () {
+    var a = '///a///b//c';
+    var b = stripStraySlashes(a);
+    print('$a => $b');
+    expect(b, 'a///b//c');
+  });
+}
\ No newline at end of file