From 8b6ff2521fa445454a15cbd0589eaea70a2fee19 Mon Sep 17 00:00:00 2001
From: "John Paul E. Balandan, CPA" <paulbalandan@gmail.com>
Date: Thu, 19 Dec 2024 14:11:43 +0800
Subject: [PATCH] Implement `EnumCaseNamingRule`

---
 src/Nexus/PHPStan/README.md                   |  1 +
 .../Rules/Enums/EnumCaseNamingRule.php        | 48 +++++++++++++++++
 src/Nexus/PHPStan/extension.neon              |  1 +
 .../Rules/Enums/EnumCaseNamingRuleTest.php    | 53 +++++++++++++++++++
 .../Rules/Enums/data/enum-case-naming.php     | 13 +++++
 5 files changed, 116 insertions(+)
 create mode 100644 src/Nexus/PHPStan/Rules/Enums/EnumCaseNamingRule.php
 create mode 100644 tests/PHPStan/Rules/Enums/EnumCaseNamingRuleTest.php
 create mode 100644 tests/PHPStan/Rules/Enums/data/enum-case-naming.php

diff --git a/src/Nexus/PHPStan/README.md b/src/Nexus/PHPStan/README.md
index a635a0d..5f5c0a5 100644
--- a/src/Nexus/PHPStan/README.md
+++ b/src/Nexus/PHPStan/README.md
@@ -32,6 +32,7 @@ The following rules will automatically be enabled once the `extension.neon` is a
     * Class properties - camelCase format with no underscores
     * Class methods - camelCase format with no underscores, except for magic methods where double
         underscores are allowed
+    * Enum cases - PascalCase format
     * Functions - lower_snake_case format
 2. `@phpstan-`-prefixed PHPDoc tags should be avoided where possible:
     * `@phpstan-var` => `@var`
diff --git a/src/Nexus/PHPStan/Rules/Enums/EnumCaseNamingRule.php b/src/Nexus/PHPStan/Rules/Enums/EnumCaseNamingRule.php
new file mode 100644
index 0000000..6efa30e
--- /dev/null
+++ b/src/Nexus/PHPStan/Rules/Enums/EnumCaseNamingRule.php
@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Nexus framework.
+ *
+ * (c) John Paul E. Balandan, CPA <paulbalandan@gmail.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Nexus\PHPStan\Rules\Enums;
+
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Rules\Rule;
+use PHPStan\Rules\RuleErrorBuilder;
+
+/**
+ * @implements Rule<Node\Stmt\EnumCase>
+ */
+final class EnumCaseNamingRule implements Rule
+{
+    public function getNodeType(): string
+    {
+        return Node\Stmt\EnumCase::class;
+    }
+
+    public function processNode(Node $node, Scope $scope): array
+    {
+        $enumCaseName = $node->name->name;
+
+        if (preg_match('/(?:[A-Z][a-z]+)+/', $enumCaseName) !== 1) {
+            return [
+                RuleErrorBuilder::message(\sprintf(
+                    'Enum case "%s" should be in PascalCase format.',
+                    $enumCaseName,
+                ))
+                    ->identifier('nexus.enumCaseNaming')
+                    ->build(),
+            ];
+        }
+
+        return [];
+    }
+}
diff --git a/src/Nexus/PHPStan/extension.neon b/src/Nexus/PHPStan/extension.neon
index 5114b0d..570374e 100644
--- a/src/Nexus/PHPStan/extension.neon
+++ b/src/Nexus/PHPStan/extension.neon
@@ -2,6 +2,7 @@ rules:
   - Nexus\PHPStan\Rules\CleanCode\AssignExprInCondRule
   - Nexus\PHPStan\Rules\CleanCode\DisallowedErrorSuppressionOperatorRule
   - Nexus\PHPStan\Rules\Constants\ClassConstantNamingRule
+  - Nexus\PHPStan\Rules\Enums\EnumCaseNamingRule
   - Nexus\PHPStan\Rules\Functions\FunctionNamingRule
   - Nexus\PHPStan\Rules\Methods\MethodNamingRule
   - Nexus\PHPStan\Rules\PhpDoc\DisallowedPhpstanDocTagRule
diff --git a/tests/PHPStan/Rules/Enums/EnumCaseNamingRuleTest.php b/tests/PHPStan/Rules/Enums/EnumCaseNamingRuleTest.php
new file mode 100644
index 0000000..e5e291f
--- /dev/null
+++ b/tests/PHPStan/Rules/Enums/EnumCaseNamingRuleTest.php
@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * This file is part of the Nexus framework.
+ *
+ * (c) John Paul E. Balandan, CPA <paulbalandan@gmail.com>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Nexus\Tests\PHPStan\Rules\Enums;
+
+use Nexus\PHPStan\Rules\Enums\EnumCaseNamingRule;
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Group;
+
+/**
+ * @internal
+ *
+ * @extends RuleTestCase<EnumCaseNamingRule>
+ */
+#[CoversClass(EnumCaseNamingRule::class)]
+#[Group('unit-test')]
+final class EnumCaseNamingRuleTest extends RuleTestCase
+{
+    public function testRule(): void
+    {
+        $this->analyse([__DIR__.'/data/enum-case-naming.php'], [
+            [
+                'Enum case "HEARTSSUIT" should be in PascalCase format.',
+                10,
+            ],
+            [
+                'Enum case "diamonds_suit" should be in PascalCase format.',
+                11,
+            ],
+            [
+                'Enum case "clubs_SUIT" should be in PascalCase format.',
+                12,
+            ],
+        ]);
+    }
+
+    protected function getRule(): Rule
+    {
+        return new EnumCaseNamingRule();
+    }
+}
diff --git a/tests/PHPStan/Rules/Enums/data/enum-case-naming.php b/tests/PHPStan/Rules/Enums/data/enum-case-naming.php
new file mode 100644
index 0000000..cf5f9c6
--- /dev/null
+++ b/tests/PHPStan/Rules/Enums/data/enum-case-naming.php
@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Nexus\Tests\PHPStan\Rules\Enums;
+
+enum CardSuits
+{
+    case SpadesSuit;
+    case HEARTSSUIT;
+    case diamonds_suit;
+    case clubs_SUIT;
+}