Don't ignore files with use function

Previously `ClassFileLocator` would enter a "function context" when it
encountered `T_FUNCTION` token, causing it to ignore subsequent classes
(thinking they are defined in a function), ultimately leading to the
file being ignored because ``ClassFileLocator`` thought there's no
(named) classes defined in the file.

Now it will additionally check that the `T_FUNCTION` token is not
preceded by `T_USE`, fixing the bug.

Author: weirdan

CHANGELOG.md

@@ -22,7 +22,7 @@ All notable changes to this project will be documented in this file, in reverse
 
 ### Fixed
 
-- Nothing.
+- [#44](https://github.com/zendframework/zend-file/pull/44) fixes an issue where ClassFileLocator would skip the file (otherwise valid class file) containing `use function`
 
 ## 2.8.0 - 2018-04-25
 

src/ClassFileLocator.php

@@ -126,7 +126,10 @@ public function accept()
                     }
                     break;
                 case T_FUNCTION:
-                    $inFunctionDeclaration = true;
+                    // `use function` should not enter function context
+                    if ($i < 2 || ! is_array($tokens[$i - 2]) || $tokens[$i - 2][0] !== T_USE) {
+                        $inFunctionDeclaration = true;
+                    }
                     break;
                 case T_TRAIT:
                 case T_CLASS:

test/ClassFileLocatorTest.php

@@ -196,4 +196,17 @@ public function testIgnoresMethodsNamedAfterKeywords()
 
         $this->assertEquals($expected, $classNames, '', 0.0, 10, true);
     }
+
+    public function testIterationFindsClassInAFileWithUseFunction()
+    {
+        $locator = new ClassFileLocator(__DIR__);
+        $found = false;
+
+        foreach ($locator as $file) {
+            if (preg_match('/ContainsUseFunction\.php$/', $file->getFilename())) {
+                $found = true;
+            }
+        }
+        $this->assertTrue($found, "Failed to find a file that contains `use function`");
+    }
 }

test/TestAsset/ContainsUseFunction.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace ZendTest\File\TestAsset;
+
+use function strlen;
+
+class ContainsUseFunction
+{
+
+}