feature #52230 [Yaml] Allow to get all the enum cases (phansys)

This PR was merged into the 7.1 branch.

Discussion
----------

[Yaml] Allow to get all the enum cases

| Q             | A
| ------------- | ---
| Branch?       | 7.1
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Issues        | n/a
| License       | MIT

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With this addition, the `!php/enum` syntax is allowed to expose an array with all the enum cases (the result from [`UnitEnum::cases()`](https://www.php.net/manual/en/unitenum.cases.php)). This is useful for cases like `choices` option from the `Choice` validation constraint:

**BEFORE**:
```yaml
App\Entity\User:
    properties:
        status:
            - Choice:
                choices:
                    - !php/enum 'App\Entity\Enum\UserStatus::Enabled'
                    - !php/enum 'App\Entity\Enum\UserStatus::Disabled'
                    - !php/enum 'App\Entity\Enum\UserStatus::Blocked'
```

**AFTER**:
```yaml
App\Entity\User:
    properties:
        status:
            - Choice:
                choices: !php/enum 'App\Entity\Enum\UserStatus'
```

Prior to the support for enumerations, this was allowed by array constants:

```yaml
App\Entity\User:
    properties:
        status:
            - Choice:
                choices: !php/const 'App\Entity\User::AVAILABLE_STATUSES'
```

Commits
-------

3286539bef [Yaml] Allow Yaml component to get all the enum cases

Author: fabpot

CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+7.1
+---
+
+ * Add support for getting all the enum cases with `!php/enum Foo`
+
 7.0
 ---
 

Inline.php

@@ -643,24 +643,31 @@ private static function evaluateScalar(string $scalar, int $flags, array &$refer
                             }
 
                             $i = 0;
-                            $enum = self::parseScalar(substr($scalar, 10), 0, null, $i, false);
-                            if ($useValue = str_ends_with($enum, '->value')) {
-                                $enum = substr($enum, 0, -7);
-                            }
-                            if (!\defined($enum)) {
+                            $enumName = self::parseScalar(substr($scalar, 10), 0, null, $i, false);
+                            $useName = str_contains($enumName, '::');
+                            $enum = $useName ? strstr($enumName, '::', true) : $enumName;
+
+                            if (!enum_exists($enum)) {
                                 throw new ParseException(sprintf('The enum "%s" is not defined.', $enum), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                             }
+                            if (!$useName) {
+                                return $enum::cases();
+                            }
+                            if ($useValue = str_ends_with($enumName, '->value')) {
+                                $enumName = substr($enumName, 0, -7);
+                            }
 
-                            $value = \constant($enum);
-
-                            if (!$value instanceof \UnitEnum) {
-                                throw new ParseException(sprintf('The string "%s" is not the name of a valid enum.', $enum), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
+                            if (!\defined($enumName)) {
+                                throw new ParseException(sprintf('The string "%s" is not the name of a valid enum.', $enumName), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                             }
+
+                            $value = \constant($enumName);
+
                             if (!$useValue) {
                                 return $value;
                             }
                             if (!$value instanceof \BackedEnum) {
-                                throw new ParseException(sprintf('The enum "%s" defines no value next to its name.', $enum), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
+                                throw new ParseException(sprintf('The enum "%s" defines no value next to its name.', $enumName), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                             }
 
                             return $value->value;

Tests/InlineTest.php

@@ -76,14 +76,21 @@ public function testParsePhpConstantThrowsExceptionWhenUndefined()
     public function testParsePhpEnumThrowsExceptionWhenUndefined()
     {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('The enum "SomeEnum::Foo" is not defined');
-        Inline::parse('!php/enum SomeEnum::Foo', Yaml::PARSE_CONSTANT);
+        $this->expectExceptionMessage('The enum "SomeEnum" is not defined');
+        Inline::parse('!php/enum SomeEnum', Yaml::PARSE_CONSTANT);
+    }
+
+    public function testParsePhpEnumThrowsExceptionWhenNameUndefined()
+    {
+        $this->expectException(ParseException::class);
+        $this->expectExceptionMessage('The string "Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum::Foo" is not the name of a valid enum');
+        Inline::parse('!php/enum Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum::Foo', Yaml::PARSE_CONSTANT);
     }
 
     public function testParsePhpEnumThrowsExceptionWhenNotAnEnum()
     {
         $this->expectException(ParseException::class);
-        $this->expectExceptionMessage('The string "PHP_INT_MAX" is not the name of a valid enum');
+        $this->expectExceptionMessage('The enum "PHP_INT_MAX" is not defined');
         Inline::parse('!php/enum PHP_INT_MAX', Yaml::PARSE_CONSTANT);
     }
 
@@ -718,6 +725,11 @@ public function testDumpUnitEnum()
         $this->assertSame("!php/enum Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum::BAR", Inline::dump(FooUnitEnum::BAR));
     }
 
+    public function testParseUnitEnumCases()
+    {
+        $this->assertSame(FooUnitEnum::cases(), Inline::parse("!php/enum Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum", Yaml::PARSE_CONSTANT));
+    }
+
     public function testParseUnitEnum()
     {
         $this->assertSame(FooUnitEnum::BAR, Inline::parse("!php/enum Symfony\Component\Yaml\Tests\Fixtures\FooUnitEnum::BAR", Yaml::PARSE_CONSTANT));