Unit tests for #2712

Author: gsherwood

tests/Core/Tokenizer/BackfillFnTokenTest.inc

@@ -57,3 +57,12 @@ $a = fn($x) => yield 'k' => $x;
 
 /* testNullableNamespace */
 $a = fn(?\DateTime $x) : ?\DateTime => $x;
+
+/* testSelfReturnType */
+fn(self $a) : self => $a;
+
+/* testParentReturnType */
+fn(parent $a) : parent => $a;
+
+/* testCallableReturnType */
+fn(callable $a) : callable => $a;

tests/Core/Tokenizer/BackfillFnTokenTest.php

@@ -459,6 +459,42 @@ public function testNullableNamespace()
     }//end testNullableNamespace()
 
 
+    /**
+     * Test arrow functions that use self/parent/callable return types.
+     *
+     * @covers PHP_CodeSniffer\Tokenizers\PHP::processAdditional
+     *
+     * @return void
+     */
+    public function testKeywordReturnTypes()
+    {
+        $tokens = self::$phpcsFile->getTokens();
+
+        $testMarkers = [
+            'Self',
+            'Parent',
+            'Callable',
+        ];
+
+        foreach ($testMarkers as $marker) {
+            $token = $this->getTargetToken('/* test'.$marker.'ReturnType */', T_FN);
+            $this->backfillHelper($token);
+
+            $this->assertSame($tokens[$token]['scope_opener'], ($token + 11), "Scope opener is not the arrow token (for $marker)");
+            $this->assertSame($tokens[$token]['scope_closer'], ($token + 14), "Scope closer is not the semicolon token(for $marker)");
+
+            $opener = $tokens[$token]['scope_opener'];
+            $this->assertSame($tokens[$opener]['scope_opener'], ($token + 11), "Opener scope opener is not the arrow token(for $marker)");
+            $this->assertSame($tokens[$opener]['scope_closer'], ($token + 14), "Opener scope closer is not the semicolon token(for $marker)");
+
+            $closer = $tokens[$token]['scope_opener'];
+            $this->assertSame($tokens[$closer]['scope_opener'], ($token + 11), "Closer scope opener is not the arrow token(for $marker)");
+            $this->assertSame($tokens[$closer]['scope_closer'], ($token + 14), "Closer scope closer is not the semicolon token(for $marker)");
+        }
+
+    }//end testKeywordReturnTypes()
+
+
     /**
      * Test that anonymous class tokens without parenthesis do not get assigned a parenthesis owner.
      *