Merge "Less_Parser: Faster matching by inlining matcher() chains"

wikimedia · Mar 26, 2024 · 9294701 · 9294701
2 parents fd334ea + b799deb
commit 9294701
Showing 1 changed file with 21 additions and 56 deletions.
diff --git a/lib/Less/Parser.php b/lib/Less/Parser.php
@@ -757,44 +757,6 @@ private function isWhitespace( $offset = 0 ) {
  return strpos( " \t\n\r\v\f", $this->input[$this->pos + $offset] ) !== false;
  }
 
- /**
- * Parse from a token, regexp or string, and move forward if match
- *
- * @param array $toks
- * @return null|string|array|Less_Tree
- */
- private function matcher( $toks ) {
- // The match is confirmed, add the match length to `this::pos`,
- // and consume any extra white-space characters (' ' || '\n')
- // which come after that. The reason for this is that LeSS's
- // grammar is mostly white-space insensitive.
- //
-
- foreach ( $toks as $tok ) {
-
- $char = $tok[0];
-
- if ( $char === '/' ) {
- $match = $this->matchReg( $tok );
- if ( $match !== null ) {
- return $match;
- }
-
- } elseif ( $char === '#' ) {
- $match = $this->matchChar( $tok[1] );
-
- } else {
- // Non-terminal, match using a function call
- $match = $this->$tok();
-
- }
-
- if ( $match ) {
- return $match;
- }
- }
- }
-
  /**
  * Match a single character in the input.
  *
@@ -869,16 +831,22 @@ private function skipWhitespace( $length ) {
  }
 
  /**
+ * Parse a token from a regexp or method name string
+ *
  * @param string $tok
  * @param string|null $msg
+ * @see less-2.5.3.js#Parser.expect
  */
  private function expect( $tok, $msg = null ) {
- $result = $this->matcher( [ $tok ] );
- if ( !$result ) {
- $this->Error( $msg ? "Expected '" . $tok . "' got '" . $this->input[$this->pos] . "'" : $msg );
+ if ( $tok[0] === '/' ) {
+ $result = $this->matchReg( $tok );
  } else {
+ $result = $this->$tok();
+ }
+ if ( $result !== null ) {
  return $result;
  }
+ $this->Error( $msg ? "Expected '" . $tok . "' got '" . $this->input[$this->pos] . "'" : $msg );
  }
 
  /**
@@ -1203,7 +1171,7 @@ private function parseEntitiesUrl() {
  return;
  }
 
- $value = $this->matcher( [ 'parseEntitiesQuoted', 'parseEntitiesVariable', '/\\Gdata\:.*?[^\)]+/', '/\\G(?:(?:\\\\[\(\)\'"])|[^\(\)\'"])+/' ] );
+ $value = $this->parseEntitiesQuoted() ?? $this->parseEntitiesVariable() ?? $this->matchReg( '/\\Gdata\:.*?[^\)]+/' ) ?? $this->matchReg( '/\\G(?:(?:\\\\[\(\)\'"])|[^\(\)\'"])+/' ) ?? null;
  if ( !$value ) {
  $value = '';
  }
@@ -1736,17 +1704,14 @@ private function parseElement() {
  $c = $this->parseCombinator();
  $index = $this->pos;
 
- // TODO: Speed up by calling matchChar directly, like less.js does
- $e = $this->matcher( [
- '/\\G(?:\d+\.\d+|\d+)%/',
- '/\\G(?:[.#]?|:*)(?:[\w-]|[^\x00-\x9f]|\\\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/',
- '#*',
- '#&',
- 'parseAttribute',
- '/\\G\([^&()@]+\)/',
- '/\\G[\.#:](?=@)/',
- 'parseEntitiesVariableCurly'
- ] );
+ $e = $this->matchReg( '/\\G(?:\d+\.\d+|\d+)%/' )
+ ?? $this->matchReg( '/\\G(?:[.#]?|:*)(?:[\w-]|[^\x00-\x9f]|\\\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/' )
+ ?? $this->matchChar( '*' )
+ ?? $this->matchChar( '&' )
+ ?? $this->parseAttribute()
+ ?? $this->matchReg( '/\\G\([^&()@]+\)/' )
+ ?? $this->matchReg( '/\\G[\.#:](?=@)/' )
+ ?? $this->parseEntitiesVariableCurly();
 
  if ( $e === null ) {
  $this->save();
@@ -1781,7 +1746,7 @@ private function parseCombinator() {
  $c = $this->input[$this->pos];
  if ( $c === '/' ) {
  $this->save();
- $slashedCombinator = $this->matcher( [ '/\/[a-z]+\//i' ] );
+ $slashedCombinator = $this->matchReg( '/\\G\/[a-z]+\//i' );
  if ( $slashedCombinator ) {
  $this->forget();
  return $slashedCombinator;
@@ -1890,7 +1855,7 @@ private function parseAttribute() {
 
  $op = $this->matchReg( '/\\G[|~*$^]?=/' );
  if ( $op ) {
- $val = $this->matcher( [ 'parseEntitiesQuoted', '/\\G[0-9]+%/', '/\\G[\w-]+/', 'parseEntitiesVariableCurly' ] );
+ $val = $this->parseEntitiesQuoted() ?? $this->matchReg( '/\\G[0-9]+%/' ) ?? $this->matchReg( '/\\G[\w-]+/' ) ?? $this->parseEntitiesVariableCurly();
  }
 
  $this->expectChar( ']' );
@@ -2440,7 +2405,7 @@ private function parseAddition() {
  $op = $this->matchReg( '/\\G[-+]\s+/' );
  if ( !$op ) {
  if ( !$isSpaced ) {
- $op = $this->matcher( [ '#+', '#-' ] );
+ $op = $this->matchChar( '+' ) ?? $this->matchChar( '-' );
  }
  if ( !$op ) {
  break;