Do not add empty PSR-4 autoload entry (#173)

Do not add empty PSR-4 autoload entry

Closes #166

Author: theofidry

src/Scoper/Composer/AutoloadPrefixer.php

@@ -14,6 +14,8 @@
 
 namespace Humbug\PhpScoper\Scoper\Composer;
 
+use function array_key_exists;
+
 /**
  * @private
  */
@@ -40,10 +42,12 @@ public static function prefixPackageAutoloads(array $contents, string $prefix):
 
     private static function prefixAutoloads(array $autoload, string $prefix): array
     {
-        $autoload['psr-4'] = isset($autoload['psr-4']) ? $autoload['psr-4'] : [];
+        if (false === array_key_exists('psr-4', $autoload) && false === array_key_exists('psr-0', $autoload)) {
+            return $autoload;
+        }
 
         if (isset($autoload['psr-0'])) {
-            $autoload['psr-4'] = self::mergePSR0And4($autoload['psr-0'], $autoload['psr-4']);
+            $autoload['psr-4'] = self::mergePSR0And4($autoload['psr-0'], $autoload['psr-4'] ?? []);
         }
         unset($autoload['psr-0']);
 

tests/Scoper/Composer/JsonFileScoperTest.php

@@ -212,6 +212,7 @@ public function providePSR0ComposerFiles()
 }
 JSON
         ];
+
         yield 'psr zero and four with the same namespace get merged' => [
             <<<'JSON'
 {
@@ -239,6 +240,7 @@ public function providePSR0ComposerFiles()
 }
 JSON
         ];
+
         yield 'psr zero and four get merged if either of them have multiple entries' => [
             <<<'JSON'
 {
@@ -290,6 +292,7 @@ public function providePSR0ComposerFiles()
 }
 JSON
         ];
+
         yield 'psr zero gets converted to psr4' => [
             <<<'JSON'
 {
@@ -311,6 +314,7 @@ public function providePSR0ComposerFiles()
 }
 JSON
         ];
+
         yield 'psr zero and four get merged when both are arrays' => [
             <<<'JSON'
 {
@@ -344,6 +348,27 @@ public function providePSR0ComposerFiles()
         }
     }
 }
+JSON
+        ];
+
+        yield [
+            <<<'JSON'
+{
+    "autoload": {
+        "classmap": ["src"]
+    }
+}
+
+JSON
+            ,
+            <<<'JSON'
+{
+    "autoload": {
+        "classmap": [
+            "src"
+        ]
+    }
+}
 JSON
         ];
     }