TASK: Narrower handle boolean literal comparisons

Author: mhsdesign

src/TypeSystem/Narrower/ExpressionTypeNarrower.php

@@ -24,6 +24,7 @@
 
 use PackageFactory\ComponentEngine\Definition\BinaryOperator;
 use PackageFactory\ComponentEngine\Parser\Ast\BinaryOperationNode;
+use PackageFactory\ComponentEngine\Parser\Ast\BooleanLiteralNode;
 use PackageFactory\ComponentEngine\Parser\Ast\ExpressionNode;
 use PackageFactory\ComponentEngine\Parser\Ast\IdentifierNode;
 use PackageFactory\ComponentEngine\Parser\Ast\NullLiteralNode;
@@ -59,15 +60,43 @@ public function narrowTypesOfSymbolsIn(ExpressionNode $expressionNode, TypeNarro
         }
 
         if (($binaryOperationNode = $expressionNode->root) instanceof BinaryOperationNode) {
-            // cases
-            // `nullableString === null ? "nullableString is null" : "nullableString is not null"`
-            // `nullableString !== null ? "nullableString is not null" : "nullableString is null"`
+            // todo we currently only work with two operands
             if (count($binaryOperationNode->operands->rest) !== 1) {
                 return NarrowedTypes::empty();
             }
             $first = $binaryOperationNode->operands->first;
             $second = $binaryOperationNode->operands->rest[0];
 
+            if (
+                ($first->root instanceof BooleanLiteralNode
+                    && ($boolean = $first->root) instanceof BooleanLiteralNode
+                    // @phpstan-ignore-next-line
+                    && $other = $second
+                ) || ($second->root instanceof BooleanLiteralNode
+                    && ($boolean = $second->root) instanceof BooleanLiteralNode
+                    // @phpstan-ignore-next-line
+                    && $other = $first
+                )
+            ) {
+                $contextBasedOnOperator = match ($binaryOperationNode->operator) {
+                    BinaryOperator::EQUAL => $context,
+                    BinaryOperator::NOT_EQUAL => $context->negate(),
+                    default => null,
+                };
+
+                if (!$contextBasedOnOperator) {
+                    return NarrowedTypes::empty();
+                }
+
+                return $this->narrowTypesOfSymbolsIn(
+                    $other,
+                    $boolean->value ? $contextBasedOnOperator : $contextBasedOnOperator->negate()
+                );
+            }
+
+            // cases
+            // `nullableString === null ? "nullableString is null" : "nullableString is not null"`
+            // `nullableString !== null ? "nullableString is not null" : "nullableString is null"`
             $comparedIdentifierValueToNull = match (true) {
                 // case `nullableString === null`
                 $first->root instanceof IdentifierNode && $second->root instanceof NullLiteralNode => $first->root->value,

test/Unit/TypeSystem/Resolver/TernaryOperation/TernaryOperationTypeResolverTest.php

@@ -45,27 +45,44 @@ public function ternaryOperationExamples(): array
             'false ? 42 : "foo"' => ['false ? 42 : "foo"', StringType::get()],
             '1 < 2 ? 42 : "foo"' => ['1 < 2 ? 42 : "foo"', UnionType::of(NumberType::get(), StringType::get())],
             '1 < 2 ? variableOfTypeString : variableOfTypeNumber' => [
-                '1 < 2 ? variableOfTypeString : variableOfTypeNumber', 
+                '1 < 2 ? variableOfTypeString : variableOfTypeNumber',
                 UnionType::of(NumberType::get(), StringType::get())
             ],
+
             'nullableString ? nullableString : "fallback"' => [
                 'nullableString ? nullableString : "fallback"', StringType::get()
             ],
+            'nullableString ? null : nullableString' => [
+                'nullableString ? null : nullableString', NullType::get()
+            ],
+
             'nullableString === null ? "" : nullableString' => [
                 'nullableString === null ? "" : nullableString', StringType::get()
             ],
+            // Patience you must have my young Padawan.
             'null === nullableString ? "" : nullableString' => [
                 'null === nullableString ? "" : nullableString', StringType::get()
             ],
+
             'nullableString !== null ? nullableString : ""' => [
                 'nullableString !== null ? nullableString : ""', StringType::get()
             ],
-            // Patience you must have my young Padawan.
             'null !== nullableString ? nullableString : ""' => [
                 'null !== nullableString ? nullableString : ""', StringType::get()
             ],
-            'nullableString ? null : nullableString' => [
-                'nullableString ? null : nullableString', NullType::get()
+
+            'true === (nullableString === null) ? "" : nullableString' => [
+                'true === (nullableString === null) ? "" : nullableString', StringType::get()
+            ],
+            'false !== (nullableString === null) ? "" : nullableString' => [
+                'false !== (nullableString === null) ? "" : nullableString', StringType::get()
+            ],
+
+            'false === (nullableString === null) ? nullableString : ""' => [
+                'false === (nullableString === null) ? nullableString : ""', StringType::get()
+            ],
+            'true !== (nullableString === null) ? nullableString : ""' => [
+                'true !== (nullableString === null) ? nullableString : ""', StringType::get()
             ],
         ];
     }