Implement runtime type assertion for iterables

alisqi · Oct 20, 2024 · 6419e34 · 6419e34
1 parent 3ea3d01
commit 6419e34
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diff --git a/README.md b/README.md
@@ -106,7 +106,7 @@ they are rendered. This is the aim of a similar project: [TwigStan](https://gith
 * ✅ Invalid type declared (e.g., `{% types {i: 'nit'} %}`)
 * ✅ Context contains variable (unless defined as optional)
 * ✅ Runtime variable is null when type is not nullable
-* ⌛ Runtime type doesn't match declaration
+* ✅ Runtime type doesn't match declaration
 * ⌛ Invalid object property or method (e.g., `{{ user.nmae }}`)
 * ⌛ Undocumented context variable (i.e., missing in `{% types %}`)
 * ⌛ Use of short-hand form (e.g., `{{ user.admin }}` instead of `isAdmin`) [Notice]

diff --git a/src/Assertion/AssertType.php b/src/Assertion/AssertType.php
@@ -6,6 +6,18 @@ final class AssertType
 {
     public static function matches($value, string $type): bool
     {
+        // convert iterable short form to canonical form (e.g., `string[]` => `iterable<string>`)
+        if (str_ends_with($type, '[]')) {
+            $type = 'iterable<' . substr($type, 0, -2) . '>';
+        }
+
+        if (str_starts_with($type, 'iterable<')) {
+            $matches = [];
+            preg_match('/<((string|number),\s*)?(.+)>/', substr($type, 8), $matches);
+            [, , $keyType, $valueType] = $matches;
+            return self::iterableMatches($value, $valueType, $keyType ?: null);
+        }
+
         return match ($type) {
             'string' => is_string($value),
             'number' => is_int($value) || is_float($value),
@@ -15,4 +27,23 @@ public static function matches($value, string $type): bool
             default => true,
         };
     }
+
+    private static function iterableMatches($iterable, string $valueType, ?string $keyType = null): bool
+    {
+        if (!is_iterable($iterable)) {
+            return false;
+        }
+
+        foreach ($iterable as $key => $value) {
+            if (!self::matches($value, $valueType)) {
+                return false;
+            }
+
+            if ($keyType !== null && !self::matches($key, $keyType)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
 }
diff --git a/tests/TypeAssertionsTest.php b/tests/TypeAssertionsTest.php
@@ -2,6 +2,7 @@
 
 namespace AlisQI\TwigQI\Tests;
 
+use ArrayIterator;
 use Exception;
 
 class TypeAssertionsTest extends AbstractTestCase
@@ -100,6 +101,46 @@ public static function getTypes(): array
             ['object', 'object', false],
             ['object', true, false],
             ['object', [], false],
+
+            ['iterable', [], true],
+            ['iterable', [13, 37], true],
+            ['iterable', new ArrayIterator([13, 37]), true],
+            ['iterable', ['foo' => 'bar'], true],
+            ['iterable', 'hello', false],
+
+            ['iterable<string>', [], true],
+            ['iterable<string>', ['hello'], true],
+            ['iterable<string>', new ArrayIterator(['hello']), true],
+            ['iterable<string>', [1337], false],
+            ['iterable<string>', 'hello', false],
+
+            ['string[]', [], true],
+            ['string[]', ['foo'], true],
+            ['string[]', 'foo', false],
+            ['string[]', [1337], false],
+
+            ['iterable<string, string>', [], true],
+            ['iterable<string, string>', ['foo' => 'bar'], true],
+            ['iterable<string, string>', new ArrayIterator(['foo' => 'bar']), true],
+            ['iterable<string, string>', ['foo' => 1337], false],
+            ['iterable<string, string>', ['foo' => ['bar']], false],
+            ['iterable<string, string>', [13, 37], false],
+
+            ['iterable<number, number>', [], true],
+            ['iterable<number, number>', [13, 37], true],
+            ['iterable<number, number>', [13 => 37], true],
+            ['iterable<number, number>', new ArrayIterator([13 => 37]), true],
+            ['iterable<number, number>', ['13' => 37], true],
+            ['iterable<number, number>', ['leet' => 1337], false],
+
+            ['iterable<string, iterable<string>>', ['foo' => ['bar']], true],
+            ['iterable<string, iterable<number>>', ['foo' => [13, 37]], true],
+            ['iterable<string, iterable<string>>', ['foo' => [13, 37]], false],
+
+            ['iterable<iterable<iterable<string, number>>>', [[[]]], true],
+            ['iterable<iterable<iterable<string, number>>>', [[['foo' => 1337]]], true],
+            ['iterable<iterable<iterable<string, number>>>', [[[13, 37]]], false],
+            ['iterable<iterable<iterable<string, number>>>', [[['foo' => 'bar']]], false],
         ];
     }