From f6787fb16935ab5d3695459a7b54b5c35a308b19 Mon Sep 17 00:00:00 2001
From: Bernhard Schussek <bschussek@gmail.com>
Date: Wed, 23 Dec 2015 14:04:48 +0100
Subject: [PATCH] Switched to a better performing algorithm for
 Glob::getStaticPrefix()

---
 CHANGELOG.md       |  3 +-
 src/Glob.php       | 66 +++++++++++++++++++++++++++-----------------
 tests/GlobTest.php | 68 ++++++++++++++++++----------------------------
 3 files changed, 69 insertions(+), 68 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 17980f1..82016cf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,8 @@ Changelog
 
 * 4.0.0 (@release_date@)
 
- * switched to a better-performing regex compilation algorithm
+ * switched to a better-performing algorithm for `Glob::toRegEx()`
+ * switched to a better-performing algorithm for `Glob::getStaticPrefix()`
  * escaping is now always enabled
 
 * 3.3.0 (2015-12-23)
diff --git a/src/Glob.php b/src/Glob.php
index 15e0957..34de929 100644
--- a/src/Glob.php
+++ b/src/Glob.php
@@ -420,33 +420,49 @@ public static function getStaticPrefix($glob, $flags = 0)
             ));
         }
 
-        $prefix = $glob;
+        $prefix = '';
+        $length = strlen($glob);
 
-        if ($flags & self::ESCAPE) {
-            // Read backslashes together with the next (the escaped) character
-            // up to the first non-escaped star/brace
-            if (preg_match('~^('.Symbol::BACKSLASH.'.|[^'.Symbol::BACKSLASH.Symbol::STAR.Symbol::L_BRACE.Symbol::QUESTION_MARK.Symbol::L_BRACKET.'])*~', $glob, $matches)) {
-                $prefix = $matches[0];
-            }
+        for ($i = 0; $i < $length; ++$i) {
+            $c = $glob[$i];
+
+            switch ($c) {
+                case '/':
+                    $prefix .= '/';
+                    if (isset($glob[$i + 3]) && '**/' === $glob[$i + 1].$glob[$i + 2].$glob[$i + 3]) {
+                        break 2;
+                    }
+                    break;
+
+                case '*':
+                case '?':
+                case '{':
+                case '[':
+                    break 2;
+
+                case '\\':
+                    if (isset($glob[$i + 1])) {
+                        switch ($glob[$i + 1]) {
+                            case '*':
+                            case '?':
+                            case '{':
+                            case '[':
+                            case '\\':
+                                $prefix .= $glob[$i + 1];
+                                ++$i;
+                                break;
 
-            // Replace escaped characters by their unescaped equivalents
-            $prefix = str_replace(
-                array('\\\\', '\\*', '\\{', '\\}', '\\?', '\\[', '\\]', '\\^'),
-                array('\\', '*', '{', '}', '?', '[', ']', '^'),
-                $prefix
-            );
-        } else {
-            $pos1 = strpos($glob, '*');
-            $pos2 = strpos($glob, '{');
-            $pos3 = strpos($glob, '?');
-            $pos4 = strpos($glob, '[');
-
-            $positions = array_filter(array($pos1, $pos2, $pos3, $pos4), function ($v) {
-                return false !== $v;
-            });
-
-            if (!empty($positions)) {
-                $prefix = substr($glob, 0, min($positions));
+                            default:
+                                $prefix .= '\\';
+                        }
+                    } else {
+                        $prefix .= '\\';
+                    }
+                    break;
+
+                default:
+                    $prefix .= $c;
+                    break;
             }
         }
 
diff --git a/tests/GlobTest.php b/tests/GlobTest.php
index 904a94e..3b8311b 100644
--- a/tests/GlobTest.php
+++ b/tests/GlobTest.php
@@ -711,9 +711,9 @@ public function testToRegexFailsIfNotAbsolute()
     /**
      * @dataProvider provideStaticPrefixes
      */
-    public function testGetStaticPrefix($glob, $prefix, $flags = 0)
+    public function testGetStaticPrefix($glob, $prefix)
     {
-        $this->assertSame($prefix, Glob::getStaticPrefix($glob, $flags));
+        $this->assertSame($prefix, Glob::getStaticPrefix($glob));
     }
 
     public function provideStaticPrefixes()
@@ -721,38 +721,26 @@ public function provideStaticPrefixes()
         return array(
             // The method assumes that the path is already consolidated
             array('/foo/baz/../*/bar/*', '/foo/baz/../'),
-            array('/foo/baz/bar*', '/foo/baz/bar'),
-            array('/foo/baz/bar\\*', '/foo/baz/bar\\'),
-            array('/foo/baz/bar\\\\*', '/foo/baz/bar\\\\'),
-            array('/foo/baz/bar{a,b}', '/foo/baz/bar'),
-            array('/foo/baz/bar\\{a,b}', '/foo/baz/bar\\'),
-            array('/foo/baz/bar\\\\{a,b}', '/foo/baz/bar\\\\'),
-            array('/foo/baz/bar?', '/foo/baz/bar'),
-            array('/foo/baz/bar\\?', '/foo/baz/bar\\'),
-            array('/foo/baz/bar\\\\?', '/foo/baz/bar\\\\'),
-            array('/foo/baz/bar[ab]', '/foo/baz/bar'),
-            array('/foo/baz/bar\\[ab]', '/foo/baz/bar\\'),
-            array('/foo/baz/bar\\\\[ab]', '/foo/baz/bar\\\\'),
-            array('/foo/baz/bar\\*', '/foo/baz/bar*', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\*', '/foo/baz/bar\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\*', '/foo/baz/bar\\*', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\\\*', '/foo/baz/bar\\\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\*\\\\', '/foo/baz/bar*\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\{a,b}', '/foo/baz/bar{a,b}', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\{a,b}', '/foo/baz/bar\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\{a,b}', '/foo/baz/bar\\{a,b}', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\\\{a,b}', '/foo/baz/bar\\\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\{a,b}\\\\', '/foo/baz/bar{a,b}\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\?', '/foo/baz/bar?', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\?', '/foo/baz/bar\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\?', '/foo/baz/bar\\?', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\\\?', '/foo/baz/bar\\\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\?\\\\', '/foo/baz/bar?\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\[ab]', '/foo/baz/bar[ab]', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\[ab]', '/foo/baz/bar\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\[ab]', '/foo/baz/bar\\[ab]', Glob::ESCAPE),
-            array('/foo/baz/bar\\\\\\\\[ab]', '/foo/baz/bar\\\\', Glob::ESCAPE),
-            array('/foo/baz/bar\\[ab]\\\\', '/foo/baz/bar[ab]\\', Glob::ESCAPE),
+            array('/foo/baz/bar\\*', '/foo/baz/bar*'),
+            array('/foo/baz/bar\\\\*', '/foo/baz/bar\\'),
+            array('/foo/baz/bar\\\\\\*', '/foo/baz/bar\\*'),
+            array('/foo/baz/bar\\\\\\\\*', '/foo/baz/bar\\\\'),
+            array('/foo/baz/bar\\*\\\\', '/foo/baz/bar*\\'),
+            array('/foo/baz/bar\\{a,b}', '/foo/baz/bar{a,b}'),
+            array('/foo/baz/bar\\\\{a,b}', '/foo/baz/bar\\'),
+            array('/foo/baz/bar\\\\\\{a,b}', '/foo/baz/bar\\{a,b}'),
+            array('/foo/baz/bar\\\\\\\\{a,b}', '/foo/baz/bar\\\\'),
+            array('/foo/baz/bar\\{a,b}\\\\', '/foo/baz/bar{a,b}\\'),
+            array('/foo/baz/bar\\?', '/foo/baz/bar?'),
+            array('/foo/baz/bar\\\\?', '/foo/baz/bar\\'),
+            array('/foo/baz/bar\\\\\\?', '/foo/baz/bar\\?'),
+            array('/foo/baz/bar\\\\\\\\?', '/foo/baz/bar\\\\'),
+            array('/foo/baz/bar\\?\\\\', '/foo/baz/bar?\\'),
+            array('/foo/baz/bar\\[ab]', '/foo/baz/bar[ab]'),
+            array('/foo/baz/bar\\\\[ab]', '/foo/baz/bar\\'),
+            array('/foo/baz/bar\\\\\\[ab]', '/foo/baz/bar\\[ab]'),
+            array('/foo/baz/bar\\\\\\\\[ab]', '/foo/baz/bar\\\\'),
+            array('/foo/baz/bar\\[ab]\\\\', '/foo/baz/bar[ab]\\'),
         );
     }
 
@@ -776,9 +764,9 @@ public function testGetBasePath($glob, $basePath, $flags = 0)
     /**
      * @dataProvider provideBasePaths
      */
-    public function testGetBasePathStream($glob, $basePath, $flags = 0)
+    public function testGetBasePathStream($glob, $basePath)
     {
-        $this->assertSame('globtest://'.$basePath, Glob::getBasePath('globtest://'.$glob, $flags));
+        $this->assertSame('globtest://'.$basePath, Glob::getBasePath('globtest://'.$glob));
     }
 
     public function provideBasePaths()
@@ -792,13 +780,9 @@ public function provideBasePaths()
             array('/foo*', '/'),
             array('/*', '/'),
             array('/foo/baz*/bar', '/foo'),
-            array('/foo/baz\\*/bar', '/foo'),
+            array('/foo/baz\\*/bar', '/foo/baz*'),
             array('/foo/baz\\\\*/bar', '/foo'),
-            array('/foo/baz\\\\\\*/bar', '/foo'),
-            array('/foo/baz*/bar', '/foo', Glob::ESCAPE),
-            array('/foo/baz\\*/bar', '/foo/baz*', Glob::ESCAPE),
-            array('/foo/baz\\\\*/bar', '/foo', Glob::ESCAPE),
-            array('/foo/baz\\\\\\*/bar', '/foo/baz\\*', Glob::ESCAPE),
+            array('/foo/baz\\\\\\*/bar', '/foo/baz\\*'),
         );
     }