Fixed bug #2616 : PSR12.Files.FileHeader false positive when file only contains docblock

Author: gsherwood

package.xml

@@ -27,6 +27,7 @@ http://pear.php.net/dtd/package-2.0.xsd">
  <license uri="https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt">BSD 3-Clause License</license>
  <notes>
   - Fixed bug #2615 : Constant visibility false positive on non-class constants
+  - Fixed bug #2616 : PSR12.Files.FileHeader false positive when file only contains docblock
   - Fixed bug #2619 : PSR12.Files.FileHeader locks up when inline comment is the last content in a file
   - Fixed bug #2621 : PSR12.Classes.AnonClassDeclaration.CloseBraceSameLine false positive for anon class passed as function argument
     -- Thanks to Martins Sipenko for the patch
@@ -1060,6 +1061,7 @@ http://pear.php.net/dtd/package-2.0.xsd">
         <file baseinstalldir="PHP/CodeSniffer" name="FileHeaderUnitTest.5.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="FileHeaderUnitTest.6.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="FileHeaderUnitTest.7.inc" role="test" />
+        <file baseinstalldir="PHP/CodeSniffer" name="FileHeaderUnitTest.8.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="FileHeaderUnitTest.php" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="ImportStatementUnitTest.inc" role="test" />
         <file baseinstalldir="PHP/CodeSniffer" name="ImportStatementUnitTest.php" role="test" />

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

@@ -154,7 +154,7 @@ public function process(File $phpcsFile, $stackPtr)
                 // Make sure there is a single blank line after
                 // this block.
                 $next = $phpcsFile->findNext(T_WHITESPACE, ($line['end'] + 1), null, true);
-                if ($tokens[$next]['line'] !== ($tokens[$line['end']]['line'] + 2)) {
+                if ($next !== false && $tokens[$next]['line'] !== ($tokens[$line['end']]['line'] + 2)) {
                     $error = 'Header blocks must be followed by a single blank line';
                     $fix   = $phpcsFile->addFixableError($error, $line['end'], 'SpacingAfterBlock');
                     if ($fix === true) {

src/Standards/PSR12/Tests/Files/FileHeaderUnitTest.8.inc

@@ -0,0 +1,5 @@
+<?php
+
+/**
+ * Comment here.
+ */