Make array_count_values return non-empty-array types.

Author: mad-briller

src/Type/Php/ArrayCountValuesDynamicReturnTypeExtension.php

@@ -6,6 +6,7 @@
 use PHPStan\Analyser\Scope;
 use PHPStan\DependencyInjection\AutowiredService;
 use PHPStan\Reflection\FunctionReflection;
+use PHPStan\Type\Accessory\NonEmptyArrayType;
 use PHPStan\Type\ArrayType;
 use PHPStan\Type\Constant\ConstantArrayType;
 use PHPStan\Type\DynamicFunctionReturnTypeExtension;
@@ -56,9 +57,9 @@ public function getTypeFromFunctionCall(
 				continue;
 			}
 
-			$outputTypes[] = new ArrayType(
-				$itemType,
-				IntegerRangeType::fromInterval(1, null),
+			$outputTypes[] = TypeCombinator::intersect(
+				new ArrayType($itemType, IntegerRangeType::fromInterval(1, null)),
+				new NonEmptyArrayType(),
 			);
 		}
 

tests/PHPStan/Analyser/nsrt/array-count-values.php

@@ -6,11 +6,11 @@
 
 $ints = array_count_values([1, 2, 2, 3]);
 
-assertType('array<1|2|3, int<1, max>>', $ints);
+assertType('non-empty-array<1|2|3, int<1, max>>', $ints);
 
 $strings = array_count_values(['one', 'two', 'two', 'three']);
 
-assertType('array<\'one\'|\'three\'|\'two\', int<1, max>>', $strings);
+assertType('non-empty-array<\'one\'|\'three\'|\'two\', int<1, max>>', $strings);
 
 $objects = array_count_values([new \stdClass()]);
 
@@ -25,7 +25,7 @@ function returnsStringOrObjectArray(): array
 }
 
 // Objects are ignored by array_count_values, with a warning emitted.
-assertType('array<string, int<1, max>>', array_count_values(returnsStringOrObjectArray()));
+assertType('non-empty-array<string, int<1, max>>', array_count_values(returnsStringOrObjectArray()));
 
 class StringableObject
 {
@@ -40,4 +40,4 @@ public function __toString(): string
 // Stringable objects are ignored by array_count_values, with a warning emitted.
 $stringable = array_count_values([new StringableObject(), 'string', 1]);
 
-assertType('array<1|\'string\', int<1, max>>', $stringable);
+assertType('non-empty-array<1|\'string\', int<1, max>>', $stringable);