PEAR/Functions/FunctionDeclaration: add extra defensive coding

When the sniff is run during live coding, the sniff could encounter a situation where a function declaration does not have a scope opener, not a function body.

In that case, the "SpaceBeforeSemicolon" check would try to find a semi-colon, presuming the function is an abstract method or interface method, but would not find one, which would result in the `if ($tokens[($end - 1)]['content'] === $phpcsFile->eolChar)` condition throwing a _"Undefined array key -1"_ notice.

Fixed now.

Includes test safeguarding the fix.

Note: this fix will, by extension, fix this same error for the `PSR2.Methods.FunctionCallSignature` sniff and the `Squiz.Functions.MultiLineFunctionDeclaration` sniff.

:point_right: this commit will be easier to review while ignoring whitespace changes.

src/Standards/PEAR/Sniffs/Functions/FunctionDeclarationSniff.php

@@ -128,23 +128,25 @@ public function process(File $phpcsFile, $stackPtr)
             // Must be no space before semicolon in abstract/interface methods.
             if ($methodProps['has_body'] === false) {
                 $end = $phpcsFile->findNext(T_SEMICOLON, $closeBracket);
-                if ($tokens[($end - 1)]['content'] === $phpcsFile->eolChar) {
-                    $spaces = 'newline';
-                } else if ($tokens[($end - 1)]['code'] === T_WHITESPACE) {
-                    $spaces = $tokens[($end - 1)]['length'];
-                } else {
-                    $spaces = 0;
-                }
+                if ($end !== false) {
+                    if ($tokens[($end - 1)]['content'] === $phpcsFile->eolChar) {
+                        $spaces = 'newline';
+                    } else if ($tokens[($end - 1)]['code'] === T_WHITESPACE) {
+                        $spaces = $tokens[($end - 1)]['length'];
+                    } else {
+                        $spaces = 0;
+                    }
 
-                if ($spaces !== 0) {
-                    $error = 'Expected 0 spaces before semicolon; %s found';
-                    $data  = [$spaces];
-                    $fix   = $phpcsFile->addFixableError($error, $end, 'SpaceBeforeSemicolon', $data);
-                    if ($fix === true) {
-                        $phpcsFile->fixer->replaceToken(($end - 1), '');
+                    if ($spaces !== 0) {
+                        $error = 'Expected 0 spaces before semicolon; %s found';
+                        $data  = [$spaces];
+                        $fix   = $phpcsFile->addFixableError($error, $end, 'SpaceBeforeSemicolon', $data);
+                        if ($fix === true) {
+                            $phpcsFile->fixer->replaceToken(($end - 1), '');
+                        }
                     }
                 }
-            }
+            }//end if
         }//end if
 
         // Must be one space before and after USE keyword for closures.

src/Standards/PEAR/Tests/Functions/FunctionDeclarationUnitTest.2.inc

@@ -0,0 +1,7 @@
+<?php
+
+// Intentional parse error/live coding test.
+// This must be the only test in this file.
+// Safeguarding that the sniff does not throw a PHP notice for this test.
+
+function liveCoding()