Fix atrocious performance in RegEx class

allejo · allejo · commit 7c4c207322eb · 2020-11-21T22:13:33.000-08:00
Forward port e98ea8f Fixes #78
diff --git a/src/Highlight/RegEx.php b/src/Highlight/RegEx.php
@@ -76,13 +76,13 @@ public function exec($str)
     {
         $index = null;
         $results = array();
-        preg_match_all($this->source, $str, $results, PREG_SET_ORDER | PREG_OFFSET_CAPTURE, $this->lastIndex);
+        preg_match($this->source, $str, $results, PREG_OFFSET_CAPTURE, $this->lastIndex);
 
         if ($results === null || count($results) === 0) {
             return null;
         }
 
-        foreach ($results[0] as &$result) {
+        foreach ($results as &$result) {
             if ($result[1] !== -1) {
                 // Only save the index if it hasn't been set yet
                 if ($index === null) {
@@ -95,7 +95,8 @@ public function exec($str)
             }
         }
 
-        $results = $results[0];
+        unset($result);
+
         $this->lastIndex += mb_strlen($results[0]) + ($index - $this->lastIndex);
 
         $matches = new RegExMatch($results);

Original file line number	Diff line number	Diff line change
`@@ -76,13 +76,13 @@ public function exec($str)`
`76`	`76`	`{`
`77`	`77`	`$index = null;`
`78`	`78`	`$results = array();`
`79`		`- preg_match_all($this->source, $str, $results, PREG_SET_ORDER \| PREG_OFFSET_CAPTURE, $this->lastIndex);`
	`79`	`+ preg_match($this->source, $str, $results, PREG_OFFSET_CAPTURE, $this->lastIndex);`
`80`	`80`
`81`	`81`	`if ($results === null \|\| count($results) === 0) {`
`82`	`82`	`return null;`
`83`	`83`	`}`
`84`	`84`
`85`		`- foreach ($results[0] as &$result) {`
	`85`	`+ foreach ($results as &$result) {`
`86`	`86`	`if ($result[1] !== -1) {`
`87`	`87`	`// Only save the index if it hasn't been set yet`
`88`	`88`	`if ($index === null) {`
`@@ -95,7 +95,8 @@ public function exec($str)`
`95`	`95`	`}`
`96`	`96`	`}`
`97`	`97`
`98`		`- $results = $results[0];`
	`98`	`+ unset($result);`
	`99`	`+`
`99`	`100`	`$this->lastIndex += mb_strlen($results[0]) + ($index - $this->lastIndex);`
`100`	`101`
`101`	`102`	`$matches = new RegExMatch($results);`