minor #550 Adds tests for Path helper. (dbrumann)

This PR was merged into the 1.8-dev branch.

Discussion
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Adds tests for Path helper.

I wanted to make sure I understand how concatenate on Path works for my
PR for #513 and maybe the tests are valuable to others as well.

Commits
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7081853 Adds tests for Path helper.

Author: nicolas-grekas

tests/PathTest.php

@@ -22,4 +22,27 @@ public function testConcatenateOnWindows()
 
         $this->assertEquals('c:\\my-project/src/kernel.php', $path->concatenate(['c:\\my-project', 'src/', 'kernel.php']));
     }
+
+    /**
+     * @dataProvider providePathsForConcatenation
+     */
+    public function testConcatenate($part1, $part2, $expectedPath)
+    {
+        $path = new Path('');
+
+        $actualPath = $path->concatenate([$part1, $part2]);
+
+        $this->assertEquals($expectedPath, $actualPath);
+    }
+
+    public function providePathsForConcatenation()
+    {
+        return [
+            [__DIR__, 'foo/bar.txt', __DIR__.'/foo/bar.txt'],
+            [__DIR__, '/foo/bar.txt', __DIR__.'/foo/bar.txt'],
+            ['', 'foo/bar.txt', '/foo/bar.txt'],
+            ['', '/foo/bar.txt', '/foo/bar.txt'],
+            ['.', 'foo/bar.txt', './foo/bar.txt'],
+        ];
+    }
 }