bug #4846 FunctionsAnalyzer - better isGlobalFunctionCall detection (SpacePossum)

This PR was merged into the 2.15 branch.

Discussion
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FunctionsAnalyzer - better isGlobalFunctionCall detection

Fixes #3051
Replaces #4251

Commits
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6a3d517 FunctionsAnalyzer - better isGlobalFunctionCall detection

Author: SpacePossum

src/Fixer/FunctionNotation/ImplodeCallFixer.php

@@ -75,7 +75,7 @@ protected function applyFix(\SplFileInfo $file, Tokens $tokens)
     {
         $functionsAnalyzer = new FunctionsAnalyzer();
 
-        foreach ($tokens as $index => $token) {
+        for ($index = \count($tokens) - 1; $index > 0; --$index) {
             if (!$tokens[$index]->equals([T_STRING, 'implode'], false)) {
                 continue;
             }

src/Tokenizer/Analyzer/FunctionsAnalyzer.php

@@ -13,8 +13,10 @@
 namespace PhpCsFixer\Tokenizer\Analyzer;
 
 use PhpCsFixer\Tokenizer\Analyzer\Analysis\ArgumentAnalysis;
+use PhpCsFixer\Tokenizer\Analyzer\Analysis\NamespaceUseAnalysis;
 use PhpCsFixer\Tokenizer\Analyzer\Analysis\TypeAnalysis;
 use PhpCsFixer\Tokenizer\CT;
+use PhpCsFixer\Tokenizer\Token;
 use PhpCsFixer\Tokenizer\Tokens;
 
 /**
@@ -23,6 +25,13 @@
 final class FunctionsAnalyzer
 {
     /**
+     * @var array
+     */
+    private $functionsAnalysis = ['tokens' => '', 'imports' => [], 'declarations' => []];
+
+    /**
+     * Important: risky because of the limited (file) scope of the tool.
+     *
      * @param int $index
      *
      * @return bool
@@ -33,15 +42,85 @@ public function isGlobalFunctionCall(Tokens $tokens, $index)
             return false;
         }
 
+        $nextIndex = $tokens->getNextMeaningfulToken($index);
+
+        if (!$tokens[$nextIndex]->equals('(')) {
+            return false;
+        }
+
+        $previousIsNamespaceSeparator = false;
         $prevIndex = $tokens->getPrevMeaningfulToken($index);
+
         if ($tokens[$prevIndex]->isGivenKind(T_NS_SEPARATOR)) {
+            $previousIsNamespaceSeparator = true;
             $prevIndex = $tokens->getPrevMeaningfulToken($prevIndex);
         }
 
-        $nextIndex = $tokens->getNextMeaningfulToken($index);
+        if ($tokens[$prevIndex]->isGivenKind([T_DOUBLE_COLON, T_FUNCTION, CT::T_NAMESPACE_OPERATOR, T_NEW, T_OBJECT_OPERATOR, CT::T_RETURN_REF, T_STRING])) {
+            return false;
+        }
+
+        if ($previousIsNamespaceSeparator) {
+            return true;
+        }
+
+        if ($tokens->isChanged() || $tokens->getCodeHash() !== $this->functionsAnalysis['tokens']) {
+            $this->buildFunctionsAnalysis($tokens);
+        }
+
+        // figure out in which namespace we are
+        $namespaceAnalyzer = new NamespacesAnalyzer();
+
+        $declarations = $namespaceAnalyzer->getDeclarations($tokens);
+        $scopeStartIndex = 0;
+        $scopeEndIndex = \count($tokens) - 1;
+        $inGlobalNamespace = false;
+
+        foreach ($declarations as $declaration) {
+            $scopeStartIndex = $declaration->getScopeStartIndex();
+            $scopeEndIndex = $declaration->getScopeEndIndex();
+
+            if ($index >= $scopeStartIndex && $index <= $scopeEndIndex) {
+                $inGlobalNamespace = '' === $declaration->getFullName();
+
+                break;
+            }
+        }
+
+        $call = strtolower($tokens[$index]->getContent());
+
+        // check if the call is to a function declared in the same namespace as the call is done,
+        // if the call is already in the global namespace than declared functions are in the same
+        // global namespace and don't need checking
+
+        if (!$inGlobalNamespace) {
+            /** @var int $functionNameIndex */
+            foreach ($this->functionsAnalysis['declarations'] as $functionNameIndex) {
+                if ($functionNameIndex < $scopeStartIndex || $functionNameIndex > $scopeEndIndex) {
+                    continue;
+                }
+
+                if (strtolower($tokens[$functionNameIndex]->getContent()) === $call) {
+                    return false;
+                }
+            }
+        }
 
-        return !$tokens[$prevIndex]->isGivenKind([T_DOUBLE_COLON, T_FUNCTION, CT::T_NAMESPACE_OPERATOR, T_NEW, T_OBJECT_OPERATOR, CT::T_RETURN_REF, T_STRING])
-            && $tokens[$nextIndex]->equals('(');
+        /** @var NamespaceUseAnalysis $functionUse */
+        foreach ($this->functionsAnalysis['imports'] as $functionUse) {
+            if ($functionUse->getStartIndex() < $scopeStartIndex || $functionUse->getEndIndex() > $scopeEndIndex) {
+                continue;
+            }
+
+            if ($call !== strtolower($functionUse->getShortName())) {
+                continue;
+            }
+
+            // global import like `use function \str_repeat;`
+            return $functionUse->getShortName() === ltrim($functionUse->getFullName(), '\\');
+        }
+
+        return true;
     }
 
     /**
@@ -119,4 +198,65 @@ public function isTheSameClassCall(Tokens $tokens, $index)
             || $tokens[$operatorIndex]->equals([T_DOUBLE_COLON, '::']) && $tokens[$referenceIndex]->equals([T_STRING, 'self'], false)
             || $tokens[$operatorIndex]->equals([T_DOUBLE_COLON, '::']) && $tokens[$referenceIndex]->equals([T_STATIC, 'static'], false);
     }
+
+    private function buildFunctionsAnalysis(Tokens $tokens)
+    {
+        $this->functionsAnalysis = [
+            'tokens' => $tokens->getCodeHash(),
+            'imports' => [],
+            'declarations' => [],
+        ];
+
+        // find declarations
+
+        if ($tokens->isTokenKindFound(T_FUNCTION)) {
+            $end = \count($tokens);
+
+            for ($i = 0; $i < $end; ++$i) {
+                // skip classy, we are looking for functions not methods
+                if ($tokens[$i]->isGivenKind(Token::getClassyTokenKinds())) {
+                    $i = $tokens->getNextTokenOfKind($i, ['(', '{']);
+
+                    if ($tokens[$i]->equals('(')) { // anonymous class
+                        $i = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $i);
+                        $i = $tokens->getNextTokenOfKind($i, ['{']);
+                    }
+
+                    $i = $tokens->findBlockEnd(Tokens::BLOCK_TYPE_CURLY_BRACE, $i);
+
+                    continue;
+                }
+
+                if (!$tokens[$i]->isGivenKind(T_FUNCTION)) {
+                    continue;
+                }
+
+                $i = $tokens->getNextMeaningfulToken($i);
+
+                if ($tokens[$i]->isGivenKind(CT::T_RETURN_REF)) {
+                    $i = $tokens->getNextMeaningfulToken($i);
+                }
+
+                if (!$tokens[$i]->isGivenKind(T_STRING)) {
+                    continue;
+                }
+
+                $this->functionsAnalysis['declarations'][] = $i;
+            }
+        }
+
+        // find imported functions
+
+        $namespaceUsesAnalyzer = new NamespaceUsesAnalyzer();
+
+        if ($tokens->isTokenKindFound(CT::T_FUNCTION_IMPORT)) {
+            $declarations = $namespaceUsesAnalyzer->getDeclarationsFromTokens($tokens);
+
+            foreach ($declarations as $declaration) {
+                if ($declaration->isFunction()) {
+                    $this->functionsAnalysis['imports'][] = $declaration;
+                }
+            }
+        }
+    }
 }

tests/Fixer/FunctionNotation/NativeFunctionInvocationFixerTest.php

@@ -592,6 +592,16 @@ public function & strlen($name) {
                     'strict' => true,
                 ],
             ],
+            [
+                '<?php
+                    use function foo\json_decode;
+                    json_decode($base);
+                ',
+                null,
+                [
+                    'include' => ['@all'],
+                ],
+            ],
         ];
     }