bug #22985 [Config] Allow empty globs (nicolas-grekas)

This PR was merged into the 3.3 branch.

Discussion
----------

[Config] Allow empty globs

| Q             | A
| ------------- | ---
| Branch?       | 3.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #22950
| License       | MIT
| Doc PR        | -

This considers globs as valid even if they return no matches when they have a prefix (and when that prefix exists, according to `$ignoreErrors`).
This means there is an edge-case:
`*.abc` with at least one match is OK, but when it has no match, it falls back to regular import, then usually will fil.
But rewriting this to `./*.abc` resolves the ambiguity and turns this into a glob that won't fail if no matches are found.

This should provide the expected behavior in most cases (but ambiguous described one of course).

Commits
-------

c5b9c1a8c8 [Config] Allow empty globs

src/Symfony/Component/Config/Loader/FileLoader.php

@@ -83,13 +83,18 @@ abstract class FileLoader extends Loader
      */
     public function import($resource, $type = null, $ignoreErrors = false, $sourceResource = null)
     {
-        if (is_string($resource) && false !== strpbrk($resource, '*?{[')) {
+        if (is_string($resource) && strlen($resource) !== $i = strcspn($resource, '*?{[')) {
             $ret = array();
-            foreach ($this->glob($resource, false, $_, true) as $path => $info) {
-                $ret[] = $this->doImport($path, $type, $ignoreErrors, $sourceResource);
+            $isSubpath = 0 !== $i && false !== strpos(substr($resource, 0, $i), '/');
+            foreach ($this->glob($resource, false, $_, $ignoreErrors || !$isSubpath) as $path => $info) {
+                if (null !== $res = $this->doImport($path, $type, $ignoreErrors, $sourceResource)) {
+                    $ret[] = $res;
+                }
+                $isSubpath = true;
             }
-            if ($ret) {
-                return count($ret) > 1 ? $ret : $ret[0];
+
+            if ($isSubpath) {
+                return isset($ret[1]) ? $ret : (isset($ret[0]) ? $ret[0] : null);
             }
         }
 
@@ -104,7 +109,7 @@ abstract class FileLoader extends Loader
         if (strlen($pattern) === $i = strcspn($pattern, '*?{[')) {
             $prefix = $pattern;
             $pattern = '';
-        } elseif (0 === $i) {
+        } elseif (0 === $i || false === strpos(substr($pattern, 0, $i), '/')) {
             $prefix = '.';
             $pattern = '/'.$pattern;
         } else {

src/Symfony/Component/Config/Tests/Loader/FileLoaderTest.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Config\Tests\Loader;
 
 use PHPUnit\Framework\TestCase;
+use Symfony\Component\Config\FileLocator;
 use Symfony\Component\Config\Loader\FileLoader;
 use Symfony\Component\Config\Loader\LoaderResolver;
 
@@ -74,6 +75,21 @@ class FileLoaderTest extends TestCase
 
         $this->assertSame('[foo]', $loader->import('[foo]'));
     }
+
+    public function testImportWithNoGlobMatch()
+    {
+        $locatorMock = $this->getMockBuilder('Symfony\Component\Config\FileLocatorInterface')->getMock();
+        $loader = new TestFileLoader($locatorMock);
+
+        $this->assertNull($loader->import('./*.abc'));
+    }
+
+    public function testImportWithSimpleGlob()
+    {
+        $loader = new TestFileLoader(new FileLocator(__DIR__));
+
+        $this->assertSame(__FILE__, strtr($loader->import('FileLoaderTest.*'), '/', DIRECTORY_SEPARATOR));
+    }
 }
 
 class TestFileLoader extends FileLoader