feat: introduce enum extractor (#42)

src/EnumExtractor.php

@@ -0,0 +1,94 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cdn77\EntityFqnExtractor;
+
+use Cdn77\EntityFqnExtractor\Exception\EnumDefinitionInFileIsInvalid;
+
+use function count;
+use function ltrim;
+use function Safe\file_get_contents;
+use function token_get_all;
+
+use const T_ENUM;
+use const T_NAME_QUALIFIED;
+use const T_NAMESPACE;
+use const T_STRING;
+use const T_WHITESPACE;
+
+final class EnumExtractor
+{
+    /** @return list<class-string> */
+    public static function all(string $filePathName): array
+    {
+        $code = file_get_contents($filePathName);
+
+        /** @var list<class-string> $enums */
+        $enums = [];
+        $namespace = '';
+        $tokens = token_get_all($code);
+        $count = count($tokens);
+
+        foreach ($tokens as $i => $token) {
+            if ($i < 2) {
+                continue;
+            }
+
+            if ($token[0] === T_NAMESPACE) {
+                for ($j = $i + 1; $j < $count; ++$j) {
+                    if ($tokens[$j][0] === T_NAME_QUALIFIED) {
+                        $namespace = $tokens[$j][1];
+
+                        break;
+                    }
+
+                    if ($tokens[$j][0] === T_STRING) {
+                        $namespace .= '\\' . $tokens[$j][1];
+
+                        continue;
+                    }
+
+                    if ($tokens[$j] === '{' || $tokens[$j] === ';') {
+                        $namespace = ltrim($namespace, '\\');
+
+                        break;
+                    }
+                }
+
+                continue;
+            }
+
+            if (
+                $tokens[$i - 2][0] !== T_ENUM
+                || $tokens[$i - 1][0] !== T_WHITESPACE
+                || $token[0] !== T_STRING
+            ) {
+                continue;
+            }
+
+            $enumName = $tokens[$i][1];
+            /** @psalm-var class-string $fqn */
+            $fqn = $namespace . '\\' . $enumName;
+            $enums[] = $fqn;
+        }
+
+        if ($enums === []) {
+            throw EnumDefinitionInFileIsInvalid::noEnum($filePathName);
+        }
+
+        return $enums;
+    }
+
+    /** @return class-string */
+    public static function get(string $filePathName): string
+    {
+        $enums = self::all($filePathName);
+
+        if (count($enums) > 1) {
+            throw EnumDefinitionInFileIsInvalid::multipleEnums($filePathName);
+        }
+
+        return $enums[0];
+    }
+}

src/Exception/EnumDefinitionInFileIsInvalid.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cdn77\EntityFqnExtractor\Exception;
+
+use InvalidArgumentException;
+use PhpParser\Error;
+
+use function Safe\sprintf;
+
+final class EnumDefinitionInFileIsInvalid extends InvalidArgumentException
+{
+    public static function cannotParse(string $filePathName, Error $error): self
+    {
+        return new self(
+            sprintf('Cannot parse file %s', $filePathName),
+            previous: $error
+        );
+    }
+
+    public static function noEnum(string $filePathName): self
+    {
+        return new self(
+            sprintf('There is no enum in a file %s', $filePathName)
+        );
+    }
+
+    public static function multipleEnums(string $filePathName): self
+    {
+        return new self(
+            sprintf('There are multiple enums in a file %s', $filePathName)
+        );
+    }
+}

tests/EnumExtractorTest.php

@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cdn77\EntityFqnExtractor\Tests;
+
+use Cdn77\EntityFqnExtractor\EnumExtractor;
+use Cdn77\EntityFqnExtractor\Exception\EnumDefinitionInFileIsInvalid;
+use Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory\EnumFixture;
+use Generator;
+
+final class EnumExtractorTest extends TestCaseBase
+{
+    public function testGet(): void
+    {
+        self::assertSame(
+            EnumFixture::class,
+            EnumExtractor::get(
+                __DIR__ . '/Fixtures/SomeDirectory/EnumFixture.php'
+            )
+        );
+    }
+
+    /**
+     * @param list<class-string> $expectedClasses
+     *
+     * @dataProvider dataProviderAll
+     */
+    public function testAll(array $expectedClasses, string $fixture): void
+    {
+        self::assertSame(
+            $expectedClasses,
+            EnumExtractor::all(__DIR__ . $fixture)
+        );
+    }
+
+    /** @return Generator<string, array{list<string>, string}> */
+    public function dataProviderAll(): Generator
+    {
+        yield 'two enums' => [
+            [
+                'Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory\Enum1',
+                'Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory\Enum2',
+            ],
+            '/Fixtures/SomeDirectory/EnumsFixture.php',
+        ];
+
+        yield 'class and interface' => [
+            [
+                'Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory\A',
+                'Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory\B',
+            ],
+            '/Fixtures/SomeDirectory/EnumInterfaceFixture.php',
+        ];
+    }
+
+    /** @dataProvider dataProviderGetThrows */
+    public function testGetThrows(string $expectedMessage, string $path): void
+    {
+        $this->expectException(EnumDefinitionInFileIsInvalid::class);
+        $this->expectExceptionMessage($expectedMessage);
+        EnumExtractor::get(__DIR__ . $path);
+    }
+
+    /** @return Generator<string, array{string, string}> */
+    public function dataProviderGetThrows(): Generator
+    {
+        yield 'class' => ['There is no enum in a file', '/Fixtures/SomeDirectory/ClassFixture.php'];
+        yield 'interface' => ['There is no enum in a file', '/Fixtures/SomeDirectory/InterfaceFixture.php'];
+        yield 'trait' => ['There is no enum in a file', '/Fixtures/SomeDirectory/TraitFixture.php'];
+        yield 'multiple enums' => [
+            'There are multiple enums in a file',
+            '/Fixtures/SomeDirectory/EnumsFixture.php',
+        ];
+    }
+}

tests/Fixtures/SomeDirectory/EnumInterfaceFixture.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory;
+
+// @codingStandardsIgnoreFile
+enum A
+{
+}
+
+interface InterfaceFixture
+{
+}
+
+enum B {
+}

tests/Fixtures/SomeDirectory/EnumsFixture.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Cdn77\EntityFqnExtractor\Fixtures\SomeDirectory;
+
+// @codingStandardsIgnoreFile
+
+enum Enum1
+{
+}
+
+enum Enum2
+{
+}