Fixed bug #2664 : PSR12.Files.OpenTag incorrectly identifies PHP file with only an opening tag

Author: gsherwood

package.xml

@@ -35,6 +35,7 @@ http://pear.php.net/dtd/package-2.0.xsd">
   - Fixed bug #2654 : Incorrect indentation for arguments of multiline function calls
   - Fixed bug #2656 : Squiz.WhiteSpace.MemberVarSpacing removes comments before first member var during auto fixing
     -- Thanks to Juliette Reinders Folmer for the patch
+  - Fixed bug #2664 : PSR12.Files.OpenTag incorrectly identifies PHP file with only an opening tag
  </notes>
  <contents>
   <dir name="/">
@@ -1074,6 +1075,7 @@ http://pear.php.net/dtd/package-2.0.xsd">
         <file baseinstalldir="PHP/CodeSniffer" name="OpenTagUnitTest.2.inc.fixed" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="OpenTagUnitTest.3.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="OpenTagUnitTest.4.inc" role="test" />
+        <file baseinstalldir="PHP/CodeSniffer" name="OpenTagUnitTest.5.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="OpenTagUnitTest.php" role="test" />
        </dir>
        <dir name="Functions">

src/Standards/PSR12/Sniffs/Files/OpenTagSniff.php

@@ -52,6 +52,11 @@ public function process(File $phpcsFile, $stackPtr)
 
         $tokens = $phpcsFile->getTokens();
         $next   = $phpcsFile->findNext(T_WHITESPACE, ($stackPtr + 1), null, true);
+        if ($next === false) {
+            // Empty file.
+            return;
+        }
+
         if ($tokens[$next]['line'] === $tokens[$stackPtr]['line']) {
             $error = 'Opening PHP tag must be on a line by itself';
             $fix   = $phpcsFile->addFixableError($error, $stackPtr, 'NotAlone');

src/Standards/PSR12/Tests/Files/OpenTagUnitTest.5.inc

@@ -0,0 +1 @@
+<?php