Add sniff to disallow alternative PHP open tags.

This sniff checks  for the alternative PHP syntaxes - ASP tags and script tags - which have been removed in PHP7:
```php
<% echo 'content'; %>
<%= 'content'; %>
<script language="php">
echo 'content';
</script>
```
Ref: http://php.net/manual/en/language.basic-syntax.phptags.php

If PHPCS is run on PHP < 7, the script tags will be fixable, provided they are correct.
If PHPCS is run on PHP < 7 + asp_tags is on, the ASP tags will be fixable.

Fixes squizlabs#1063

Similar to squizlabs#1069, the `myconfig5.ini` and `myconfig57.ini` files and the adjustment to the travis script are needed for the fixer unit tests to pass as when asp_tags is set to off, the fixer won't fix it correctly and the tests will fail ;-)

.travis.yml

@@ -11,7 +11,8 @@ php:
   - hhvm
 
 before_script:
-  - if [ $TRAVIS_PHP_VERSION != "hhvm" ]; then phpenv config-add myconfig.ini; fi
+  - if [[ $TRAVIS_PHP_VERSION != "7.0" && $TRAVIS_PHP_VERSION != "nightly" && $TRAVIS_PHP_VERSION != "hhvm" ]]; then mv -f myconfig5.ini myconfig.ini; phpenv config-add myconfig.ini; fi
+  - if [[ $TRAVIS_PHP_VERSION == "7.0" || $TRAVIS_PHP_VERSION == "nightly" ]]; then mv -f myconfig57.ini myconfig.ini; phpenv config-add myconfig.ini; fi
 
 script:
   - if [ $TRAVIS_PHP_VERSION != "hhvm" ]; then php scripts/phpcs --config-set php_path php; fi

CodeSniffer/Standards/Generic/Docs/PHP/DisallowAlternativePHPTagsStandard.xml

@@ -0,0 +1,7 @@
+<documentation title="Alternative PHP Code Tags">
+    <standard>
+    <![CDATA[
+    Always use <?php ?> to delimit PHP code, do not use the ASP <% %> style tags nor the <script language="php"></script> tags. This is the most portable way to include PHP code on differing operating systems and setups.
+    ]]>
+    </standard>
+</documentation>

CodeSniffer/Standards/Generic/Sniffs/PHP/DisallowAlternativePHPTagsSniff.php

@@ -0,0 +1,253 @@
+<?php
+/**
+ * Generic_Sniffs_PHP_DisallowAlternativePHPTagsSniff.
+ *
+ * PHP version 5
+ *
+ * @category  PHP
+ * @package   PHP_CodeSniffer
+ * @author    Greg Sherwood <[email protected]>
+ * @author    Marc McIntyre <[email protected]>
+ * @copyright 2006-2014 Squiz Pty Ltd (ABN 77 084 670 600)
+ * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ * @link      http://pear.php.net/package/PHP_CodeSniffer
+ */
+
+/**
+ * Generic_Sniffs_PHP_DisallowAlternativePHPTagsSniff.
+ *
+ * Verifies that no alternative PHP tags are used.
+ *
+ * If alternative PHP open tags are found, this sniff can fix both the open and close tags.
+ *
+ * @category  PHP
+ * @package   PHP_CodeSniffer
+ * @author    Greg Sherwood <[email protected]>
+ * @author    Marc McIntyre <[email protected]>
+ * @copyright 2006-2014 Squiz Pty Ltd (ABN 77 084 670 600)
+ * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
+ * @version   Release: @package_version@
+ * @link      http://pear.php.net/package/PHP_CodeSniffer
+ */
+class Generic_Sniffs_PHP_DisallowAlternativePHPTagsSniff implements PHP_CodeSniffer_Sniff
+{
+
+
+    /**
+     * Whether ASP tags are enabled or not.
+     *
+     * @var bool
+     */
+    private $_aspTags = false;
+
+
+    /**
+     * Returns an array of tokens this test wants to listen for.
+     *
+     * @return array
+     */
+    public function register()
+    {
+        if (PHP_VERSION_ID < 70000) {
+            $this->_aspTags = (boolean) ini_get('asp_tags');
+        }
+
+        return array(
+                T_OPEN_TAG,
+                T_OPEN_TAG_WITH_ECHO,
+                T_INLINE_HTML,
+               );
+
+    }//end register()
+
+
+    /**
+     * Processes this test, when one of its tokens is encountered.
+     *
+     * @param PHP_CodeSniffer_File $phpcsFile The file being scanned.
+     * @param int                  $stackPtr  The position of the current token
+     *                                        in the stack passed in $tokens.
+     *
+     * @return void
+     */
+    public function process(PHP_CodeSniffer_File $phpcsFile, $stackPtr)
+    {
+        $tokens  = $phpcsFile->getTokens();
+        $openTag = $tokens[$stackPtr];
+        $content = $openTag['content'];
+
+        if (trim($content) === '') {
+            return;
+        }
+
+        if (T_OPEN_TAG === $openTag['code']) {
+            if ('<%' === $content) {
+                $error    = 'ASP style opening tag used; expected "<?php" but found "%s"';
+                $closer   = $this->findClosingTag($phpcsFile, $tokens, $stackPtr, '%>');
+                $error_id = 'ASPOpenTagFound';
+            } else if (false !== strpos($content, '<script ')) {
+                $error    = 'Script style opening tag used; expected "<?php" but found "%s"';
+                $closer   = $this->findClosingTag($phpcsFile, $tokens, $stackPtr, '</script>');
+                $error_id = 'ScriptOpenTagFound';
+            }
+
+            if (isset($error, $closer, $error_id) === true) {
+                $data = array($content);
+
+                if (false === $closer) {
+                    $phpcsFile->addError($error, $stackPtr, $error_id, $data);
+                } else {
+                    $fix = $phpcsFile->addFixableError($error, $stackPtr, $error_id, $data);
+                    if (true === $fix) {
+                        $this->addChangeset($phpcsFile, $tokens, $stackPtr, $closer);
+                    }
+                }
+            }
+
+            return;
+        }//end if
+
+        if (T_OPEN_TAG_WITH_ECHO === $openTag['code'] && '<%=' === $content) {
+            $error   = 'ASP style opening tag used with echo; expected "<?php echo %s ..." but found "%s %s ..."';
+            $nextVar = $phpcsFile->findNext(T_WHITESPACE, ($stackPtr + 1), null, true);
+            $snippet = $this->getSnippet($tokens[$nextVar]['content']);
+            $data    = array(
+                        $snippet,
+                        $content,
+                        $snippet,
+                       );
+
+            $closer = $this->findClosingTag($phpcsFile, $tokens, $stackPtr, '%>');
+
+            if (false === $closer) {
+                $phpcsFile->addError($error, $stackPtr, 'ASPShortOpenTagFound', $data);
+            } else {
+                $fix = $phpcsFile->addFixableError($error, $stackPtr, 'ASPShortOpenTagFound', $data);
+                if (true === $fix) {
+                    $this->addChangeset($phpcsFile, $tokens, $stackPtr, $closer, true);
+                }
+            }
+
+            return;
+        }//end if
+
+        // Account for incorrect script open tags. The "(?:<s)?" in the regex is to work-around a bug in PHP 5.2.
+        if (T_INLINE_HTML === $openTag['code'] && 1 === preg_match('`((?:<s)?cript (?:[^>]+)?language=[\'"]?php[\'"]?(?:[^>]+)?>)`i', $content, $match)) {
+            $error   = 'Script style opening tag used; expected "<?php" but found "%s"';
+            $snippet = $this->getSnippet($content, $match[1]);
+            $data    = array($match[1].$snippet);
+
+            $phpcsFile->addError($error, $stackPtr, 'ScriptOpenTagFound', $data);
+
+            return;
+        }
+
+        if (T_INLINE_HTML === $openTag['code'] && false === $this->_aspTags) {
+            if (false !== strpos($content, '<%=')) {
+                $error   = 'Possible use of ASP style short opening tags detected. Needs manual inspection. Found: %s';
+                $snippet = $this->getSnippet($content, '<%=');
+                $data    = array('<%='.$snippet);
+
+                $phpcsFile->addWarning($error, $stackPtr, 'MaybeASPShortOpenTagFound', $data);
+            } else if (false !== strpos($content, '<%')) {
+                $error   = 'Possible use of ASP style opening tags detected. Needs manual inspection. Found: %s';
+                $snippet = $this->getSnippet($content, '<%');
+                $data    = array('<%'.$snippet);
+
+                $phpcsFile->addWarning($error, $stackPtr, 'MaybeASPOpenTagFound', $data);
+            }
+        }
+
+    }//end process()
+
+
+    /**
+     * Get a snippet from a HTML token.
+     *
+     * @param string $content  The content of the HTML token.
+     * @param string $start_at Partial string to use as a starting point for the snippet.
+     * @param int    $length   The target length of the snippet to get. Defaults to 40.
+     *
+     * @return string
+     */
+    protected function getSnippet($content, $start_at = '', $length = 40)
+    {
+        $start_pos = 0;
+
+        if ($start_at !== '') {
+            $start_pos = strpos($content, $start_at);
+            if ($start_pos !== false) {
+                $start_pos += strlen($start_at);
+            }
+        }
+
+        $snippet = substr($content, $start_pos, $length);
+        if ((strlen($content) - $start_pos) > $length) {
+            $snippet .= '...';
+        }
+
+        return $snippet;
+
+    }//end getSnippet()
+
+
+    /**
+     * Try and find a matching PHP closing tag.
+     *
+     * @param PHP_CodeSniffer_File $phpcsFile The file being scanned.
+     * @param array                $tokens    The token stack.
+     * @param int                  $stackPtr  The position of the current token
+     *                                        in the stack passed in $tokens.
+     * @param string               $content   The expected content of the closing tag to match the opener.
+     *
+     * @return int|false Pointer to the position in the stack for the closing tag or false if not found.
+     */
+    protected function findClosingTag(PHP_CodeSniffer_File $phpcsFile, $tokens, $stackPtr, $content)
+    {
+        $closer = $phpcsFile->findNext(T_CLOSE_TAG, ($stackPtr + 1));
+
+        if ($closer !== false && $content === trim($tokens[$closer]['content'])) {
+            return $closer;
+        }
+
+        return false;
+
+    }//end findClosingTag()
+
+
+    /**
+     * Add a changeset to replace the alternative PHP tags.
+     *
+     * @param PHP_CodeSniffer_File $phpcsFile         The file being scanned.
+     * @param array                $tokens            The token stack.
+     * @param int                  $open_tag_pointer  Stack pointer to the PHP open tag.
+     * @param int                  $close_tag_pointer Stack pointer to the PHP close tag.
+     * @param bool                 $echo              Whether to add 'echo' or not.
+     *
+     * @return void
+     */
+    protected function addChangeset(PHP_CodeSniffer_File $phpcsFile, $tokens, $open_tag_pointer, $close_tag_pointer, $echo = false)
+    {
+        // Build up the open tag replacement and make sure there's always whitespace behind it.
+        $open_replacement = '<?php';
+        if ($echo === true) {
+            $open_replacement .= ' echo';
+        }
+
+        if ($tokens[($open_tag_pointer + 1)]['code'] !== T_WHITESPACE) {
+            $open_replacement .= ' ';
+        }
+
+        // Make sure we don't remove any line breaks after the closing tag.
+        $regex = '`'.preg_quote(trim($tokens[$close_tag_pointer]['content'])).'`';
+        $close_replacement = preg_replace($regex, '?>', $tokens[$close_tag_pointer]['content']);
+
+        $phpcsFile->fixer->beginChangeset();
+        $phpcsFile->fixer->replaceToken($open_tag_pointer, $open_replacement);
+        $phpcsFile->fixer->replaceToken($close_tag_pointer, $close_replacement);
+        $phpcsFile->fixer->endChangeset();
+
+    }//end addChangeset()
+
+
+}//end class

CodeSniffer/Standards/Generic/Tests/PHP/DisallowAlternativePHPTagsUnitTest.1.inc

@@ -0,0 +1,14 @@
+<div>
+<?php echo $var; ?>
+Some content here.
+<script language="php">
+echo $var;
+</script>
+<script language='php'>echo $var;</script>
+<script type="text/php" language="php">
+echo $var;
+</script>
+<script language='PHP' type='text/php'>
+echo $var;
+</script>
+</div>

CodeSniffer/Standards/Generic/Tests/PHP/DisallowAlternativePHPTagsUnitTest.1.inc.fixed

@@ -0,0 +1,14 @@
+<div>
+<?php echo $var; ?>
+Some content here.
+<?php
+echo $var;
+?>
+<?php echo $var;?>
+<script type="text/php" language="php">
+echo $var;
+</script>
+<script language='PHP' type='text/php'>
+echo $var;
+</script>
+</div>

CodeSniffer/Standards/Generic/Tests/PHP/DisallowAlternativePHPTagsUnitTest.2.inc

@@ -0,0 +1,6 @@
+<div>
+<% echo $var; %>
+<p>Some text <% echo $var; %> and some more text</p>
+<%= $var . ' and some more text to make sure the snippet works'; %>
+<p>Some text <%= $var %> and some more text</p>
+</div>

CodeSniffer/Standards/Generic/Tests/PHP/DisallowAlternativePHPTagsUnitTest.2.inc.fixed

@@ -0,0 +1,6 @@
+<div>
+<?php echo $var; ?>
+<p>Some text <?php echo $var; ?> and some more text</p>
+<?php echo $var . ' and some more text to make sure the snippet works'; ?>
+<p>Some text <?php echo $var ?> and some more text</p>
+</div>