Added support for ConstantString unions in DuplicateKeysInLiteralArraysRule

Author: zonuexe

Diff for: src/Rules/Arrays/DuplicateKeysInLiteralArraysRule.php

@@ -9,7 +9,6 @@
 use PHPStan\Rules\Rule;
 use PHPStan\Rules\RuleErrorBuilder;
 use PHPStan\Type\Constant\ConstantIntegerType;
-use PHPStan\Type\ConstantScalarType;
 use function array_keys;
 use function count;
 use function implode;
@@ -79,29 +78,29 @@ public function processNode(Node $node, Scope $scope): array
 				}
 			}
 
-			if (!$keyType instanceof ConstantScalarType) {
+			if (count($keyType->getConstantScalarValues()) === 0) {
 				$autoGeneratedIndex = false;
 				continue;
 			}
 
-			$value = $keyType->getValue();
-			$printedValue = $key !== null
-				? $this->exprPrinter->printExpr($key)
-				: $value;
+			foreach ($keyType->getConstantScalarValues() as $value) {
+				$printedValue = $key !== null
+					? $this->exprPrinter->printExpr($key)
+					: $value;
+				$printedValues[$value][] = $printedValue;
 
-			$printedValues[$value][] = $printedValue;
+				if (!isset($valueLines[$value])) {
+					$valueLines[$value] = $item->getStartLine();
+				}
 
-			if (!isset($valueLines[$value])) {
-				$valueLines[$value] = $item->getStartLine();
-			}
+				$previousCount = count($values);
+				$values[$value] = $printedValue;
+				if ($previousCount !== count($values)) {
+					continue;
+				}
 
-			$previousCount = count($values);
-			$values[$value] = $printedValue;
-			if ($previousCount !== count($values)) {
-				continue;
+				$duplicateKeys[$value] = true;
 			}
-
-			$duplicateKeys[$value] = true;
 		}
 
 		$messages = [];

Diff for: tests/PHPStan/Rules/Arrays/DuplicateKeysInLiteralArraysRuleTest.php

@@ -61,6 +61,18 @@ public function testDuplicateKeys(): void
 				'Array has 2 duplicate keys with value -41 (-41, -41).',
 				76,
 			],
+			[
+				'Array has 2 duplicate keys with value \'foo\' (\'foo\', $key).',
+				102,
+			],
+			[
+				'Array has 2 duplicate keys with value \'bar\' (\'bar\', $key).',
+				103,
+			],
+			[
+				'Array has 2 duplicate keys with value \'key\' (\'key\', $key2).',
+				105,
+			],
 		]);
 	}
 

Diff for: tests/PHPStan/Rules/Arrays/data/duplicate-keys.php

@@ -92,4 +92,19 @@ public function doWithoutKeys(int $int)
 		];
 	}
 
+	/**
+	 * @param 'foo'|'bar' $key
+	 */
+	public function doUnionKeys(string $key): void
+	{
+		$key2 = 'key';
+		$a = [
+			'foo' => 'foo',
+			'bar' => 'bar',
+			$key => 'foo|bar',
+			'key' => 'bar',
+			$key2 => 'foo',
+		];
+	}
+
 }