Re: [PATCH] reserved words allowed as function/method names

Patches added to http://bugs.php.net/28261, and I re-opened the bug. Greg Gregory Beaver wrote: > Hi, > > I spent a while tonight tinkering with the parser to try to figure out > how to allow it to use T_IMPORT as well as T_STRING for method names, > and quickly came to the conclusion that this causes way more trouble > than it is worth. However, in a moment of inspiration, I realized that > a minor change in the lexer would allow any reserved words for method > names. The patch is attached. This patch allows all kinds of odd > looking code that probably won't be used, but permanently guarantees > that code written for PHP now will never conflict with future reserved > words: > > <?php > namespace testing; > class Test { > function array() > { > echo "array\n"; > } > function class() > { > echo "class\n"; > } > static function import() > { > echo "import\n"; > } > function new() > { > echo "new\n"; > } > $a = new Test; > $a->array(); > $a->class(); > $a->new(); > Test::import(); > testing::Test::import(); > ?> > > The patch does not allow reserved names for class names, interface > names, functions, or for class constants. This would be much harder to > implement in the lexer, and in my experience collisions with reserved > words most often happens with methods. > > The patch only allows methods to use reserved words, not functions, and > causes a fatal error with this code: > > <?php > function foreach($a) > { > } > ?> > > This prevents this wtf code, which would also produce a different (and > non-intuitive) fatal error: > > <?php > foreach (foreach() as $foreach) {foreach();} > ?> > > The patch is against PHP 5.3, and PHP 6 > > Greg > > > ------------------------------------------------------------------------ > > ? better_halt.patch.txt > ? config.cli > ? config.nice.nodebug > ? err > ? install-pear-nozlib.phar > ? run-tests.oops.patch.txt > ? smarter_lexer.patch.txt > ? test-phar.sh > ? test.phar > ? testme.php > ? zlib.patch > ? Zend/tests/zend_function_name.phpt > ? ext/gd/run-tests.php > ? ext/gettext/run-tests.php > ? ext/mysqli/run-tests.php > ? ext/zip/run-tests.php > ? ext/zlib/zlib_filter.c.2 > ? pear/scripts > ? tests/lang/halt_compiler1.phpt > ? tests/lang/halt_compiler2.phpt > ? tests/lang/halt_compiler3.phpt > ? tests/lang/halt_compiler4.phpt > Index: run-tests.php > =================================================================== > RCS file: /repository/php-src/run-tests.php,v > retrieving revision 1.226.2.37.2.35 > diff -u -r1.226.2.37.2.35 run-tests.php > --- run-tests.php 14 Sep 2007 15:28:03 -0000 1.226.2.37.2.35 > +++ run-tests.php 3 Oct 2007 02:40:57 -0000 > @@ -1328,12 +1328,15 @@ > $raw_lines = explode("\n", $post); > > $request = ''; > + $started = false; > foreach ($raw_lines as $line) { > if (empty($env['CONTENT_TYPE']) && > preg_match('/^Content-Type:(.*)/i', $line, $res)) { > $env['CONTENT_TYPE'] = trim(str_replace("\r", '', $res[1])); > continue; > } > - $request .= $line . "\n"; > + if ($started) $request .= "\n"; > + $started = true; > + $request .= $line; > } > > $env['CONTENT_LENGTH'] = strlen($request); > Index: Zend/zend_language_scanner.l > =================================================================== > RCS file: /repository/ZendEngine2/zend_language_scanner.l,v > retrieving revision 1.131.2.11.2.13.2.1 > diff -u -r1.131.2.11.2.13.2.1 zend_language_scanner.l > --- Zend/zend_language_scanner.l 28 Sep 2007 19:52:50 -0000 1.131.2.11.2.13.2.1 > +++ Zend/zend_language_scanner.l 3 Oct 2007 02:41:02 -0000 > @@ -978,6 +978,9 @@ > } > > <ST_IN_SCRIPTING>"function" { > + if (CG(active_class_entry)) { > + yy_push_state(ST_LOOKING_FOR_PROPERTY TSRMLS_CC); > + } > return T_FUNCTION; > } > > @@ -1118,6 +1121,14 @@ > return T_OBJECT_OPERATOR; > } > > +<ST_LOOKING_FOR_PROPERTY>{WHITESPACE} { > + zendlval->value.str.val = yytext; /* no copying - intentional */ > + zendlval->value.str.len = yyleng; > + zendlval->type = IS_STRING; > + HANDLE_NEWLINES(yytext, yyleng); > + return T_WHITESPACE; > +} > + > <ST_LOOKING_FOR_PROPERTY>{LABEL} { > yy_pop_state(TSRMLS_C); > zend_copy_value(zendlval, yytext, yyleng); > @@ -1131,6 +1142,7 @@ > } > > <ST_IN_SCRIPTING>"::" { > + yy_push_state(ST_LOOKING_FOR_PROPERTY TSRMLS_CC); > return T_PAAMAYIM_NEKUDOTAYIM; > } > > > > ------------------------------------------------------------------------ > > Index: Zend/zend_language_scanner.l > =================================================================== > RCS file: /repository/ZendEngine2/zend_language_scanner.l,v > retrieving revision 1.170 > diff -u -r1.170 zend_language_scanner.l > --- Zend/zend_language_scanner.l 9 Sep 2007 22:49:31 -0000 1.170 > +++ Zend/zend_language_scanner.l 3 Oct 2007 02:42:31 -0000 > @@ -1483,6 +1483,9 @@ > } > > <ST_IN_SCRIPTING>"function" { > + if (CG(active_class_entry)) { > + yy_push_state(ST_LOOKING_FOR_PROPERTY TSRMLS_CC); > + } > return T_FUNCTION; > } > > @@ -1627,6 +1630,14 @@ > return T_OBJECT_OPERATOR; > } > > +<ST_LOOKING_FOR_PROPERTY>{WHITESPACE} { > + Z_STRVAL_P(zendlval) = yytext; /* no copying - intentional */ > + Z_STRLEN_P(zendlval) = yyleng; > + Z_TYPE_P(zendlval) = IS_STRING; > + HANDLE_NEWLINES(yytext, yyleng); > + return T_WHITESPACE; > +} > + > <ST_LOOKING_FOR_PROPERTY>{LABEL} { > yy_pop_state(TSRMLS_C); > if (!zend_copy_scanner_string(zendlval, yytext, yyleng, UG(unicode)?IS_UNICODE:IS_STRING, > SCNG(output_conv) TSRMLS_CC)) { > @@ -1644,6 +1655,7 @@ > } > > <ST_IN_SCRIPTING>"::" { > + yy_push_state(ST_LOOKING_FOR_PROPERTY TSRMLS_CC); > return T_PAAMAYIM_NEKUDOTAYIM; > } >