VariableAnalysisSniff::checkForVariableVariable(): fix comment tolerance (#151)

PHP ignores comments in unexpected/unconventional places and so should the sniff.

Includes adjusting an existing unit test.

Without the fix, the adjusted unit test would cause test failures.

Author: jrfnl

VariableAnalysis/Sniffs/CodeAnalysis/VariableAnalysisSniff.php

@@ -787,13 +787,19 @@ protected function checkForAssignment(File $phpcsFile, $stackPtr, $varName, $cur
   protected function checkForVariableVariable(File $phpcsFile, $stackPtr, $varName, $currScope) {
     $tokens = $phpcsFile->getTokens();
 
-    if (!isset($tokens[$stackPtr - 1]['code'])) {
+    $prev = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($stackPtr - 1), null, true);
+    if ($prev === false) {
       return false;
     }
-    if ($tokens[$stackPtr - 1]['code'] === T_DOLLAR) {
+    if ($tokens[$prev]['code'] === T_DOLLAR) {
       return true;
     }
-    if ($tokens[$stackPtr - 1]['code'] === T_OPEN_CURLY_BRACKET && isset($tokens[$stackPtr - 2]['code']) && $tokens[$stackPtr - 2]['code'] === T_DOLLAR) {
+    if ($tokens[$prev]['code'] !== T_OPEN_CURLY_BRACKET) {
+      return false;
+    }
+
+    $prevPrev = $phpcsFile->findPrevious(Tokens::$emptyTokens, ($prev - 1), null, true);
+    if ($prevPrev !== false && $tokens[$prevPrev]['code'] === T_DOLLAR) {
       return true;
     }
     return false;

VariableAnalysis/Tests/CodeAnalysis/fixtures/VariableVariablesFixture.php

@@ -15,7 +15,7 @@ function usedVariableVariableInEcho() {
 function usedVariableVariableInLeftAssignment() {
     $foo = true; // the below is assignment, not a read, so this should be a warning
     $marName = 'foo';
-    $$marName = false;
+    $ /* comment */ $marName = false;
 }
 
 function usedVariableVariableInRightAssignment() {