From 03f7c263fedd20febfde984a3554b6df0d7c60aa Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 13 Aug 2023 05:41:08 +0200
Subject: [PATCH] Correct type for `$enum->name`

---
 .../Fetch/AtomicPropertyFetchAnalyzer.php     | 33 ++++++++++++-----
 tests/EnumTest.php                            | 36 +++++++++++++++++++
 2 files changed, 60 insertions(+), 9 deletions(-)

diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzer.php
index 663679383..d6289b668 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/AtomicPropertyFetchAnalyzer.php
@@ -228,7 +228,7 @@ class AtomicPropertyFetchAnalyzer
                 self::handleEnumValue($statements_analyzer, $stmt, $stmt_var_type, $class_storage);
             } elseif ($prop_name === 'name') {
                 $has_valid_fetch_type = true;
-                self::handleEnumName($statements_analyzer, $stmt, $lhs_type_part);
+                self::handleEnumName($statements_analyzer, $stmt, $stmt_var_type, $class_storage);
             } else {
                 self::handleNonExistentProperty(
                     $statements_analyzer,
@@ -979,16 +979,31 @@ class AtomicPropertyFetchAnalyzer
     private static function handleEnumName(
         StatementsAnalyzer $statements_analyzer,
         PropertyFetch $stmt,
-        Atomic $lhs_type_part
+        Union $stmt_var_type,
+        ClassLikeStorage $class_storage
     ): void {
-        if ($lhs_type_part instanceof TEnumCase) {
-            $statements_analyzer->node_data->setType(
-                $stmt,
-                new Union([Type::getAtomicStringFromLiteral($lhs_type_part->case_name)]),
-            );
-        } else {
-            $statements_analyzer->node_data->setType($stmt, Type::getNonEmptyString());
+        $relevant_enum_cases = array_filter(
+            $stmt_var_type->getAtomicTypes(),
+            static fn(Atomic $type): bool => $type instanceof TEnumCase,
+        );
+        $relevant_enum_case_names = array_map(
+            static fn(TEnumCase $enumCase): string => $enumCase->case_name,
+            $relevant_enum_cases,
+        );
+
+        if (empty($relevant_enum_case_names)) {
+            $relevant_enum_case_names = array_keys($class_storage->enum_cases);
         }
+
+        $statements_analyzer->node_data->setType(
+            $stmt,
+            empty($relevant_enum_case_names)
+                ? Type::getNonEmptyString()
+                : new Union(array_map(
+                    fn(string $name): TString => Type::getAtomicStringFromLiteral($name),
+                    $relevant_enum_case_names,
+                )),
+        );
     }
 
     private static function handleEnumValue(
diff --git a/tests/EnumTest.php b/tests/EnumTest.php
index 481824c10..1ac88b1c2 100644
--- a/tests/EnumTest.php
+++ b/tests/EnumTest.php
@@ -574,6 +574,42 @@ class EnumTest extends TestCase
                 'ignored_issues' => [],
                 'php_version' => '8.1',
             ],
+            'nameTypeOnKnownCases' => [
+                'code' => <<<'PHP'
+                    <?php
+                    enum Transport: string {
+                        case CAR = 'car';
+                        case BIKE = 'bike';
+                        case BOAT = 'boat';
+                    }
+
+                    $val = Transport::from(uniqid());
+                    $_name = $val->name;
+                    PHP,
+                'assertions' => [
+                    '$_name===' => "'BIKE'|'BOAT'|'CAR'",
+                ],
+                'ignored_issues' => [],
+                'php_version' => '8.1',
+            ],
+            'nameTypeOnUnknownCases' => [
+                'code' => <<<'PHP'
+                    <?php
+                    enum Transport: string {
+                        case CAR = 'car';
+                        case BIKE = 'bike';
+                        case BOAT = 'boat';
+                    }
+
+                    function f(Transport $e): void {
+                        $_name = $e->name;
+                        /** @psalm-check-type-exact $_name='BIKE'|'BOAT'|'CAR' */;
+                    }
+                    PHP,
+                'assertions' => [],
+                'ignored_issues' => [],
+                'php_version' => '8.1',
+            ],
         ];
     }