Test the constant condition and side effect checks of the ternary rule

The constant condition and float checks now read the constant values,
and the object check uses isObject(), so a mutant of them changes the
result. New test cases cover a constant condition and a function that
can have side effects.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: 2 people

src/Rules/Comparison/UnnecessaryTernaryOperatorRule.php

@@ -20,6 +20,7 @@
 use PHPStan\Type\ObjectWithoutClassType;
 use PHPStan\Type\TypeCombinator;
 use function count;
+use function is_float;
 use function is_string;
 use function sprintf;
 
@@ -77,7 +78,7 @@ private function check(Node\Expr\Ternary $node, Scope $scope): ?IdentifierRuleEr
 	{
 		// TernaryOperatorConstantConditionRule already reports these
 		$conditionType = $this->helper->getBooleanType($scope, $node->cond);
-		if ($conditionType->isTrue()->yes() || $conditionType->isFalse()->yes()) {
+		if (count($conditionType->getConstantScalarValues()) === 1) {
 			return null;
 		}
 
@@ -173,7 +174,13 @@ private function isAlwaysResult(Scope $branchScope, Expr $result, Scope $scope,
 		}
 
 		// 0.0 === -0.0, so `$f ?: 0.0` turns -0.0 into 0.0
-		return $otherType->isFloat()->no();
+		foreach ($otherType->getConstantScalarValues() as $value) {
+			if (is_float($value)) {
+				return false;
+			}
+		}
+
+		return true;
 	}
 
 	/**
@@ -197,12 +204,11 @@ private function isTruthinessNarrowedExactly(Expr $cond, Scope $scope, bool $nat
 		}
 
 		$type = $native ? $scope->getNativeType($cond) : $scope->getType($cond);
-		$objectType = new ObjectWithoutClassType();
-		if ($objectType->isSuperTypeOf($type)->no()) {
+		if ($type->isObject()->no()) {
 			return true;
 		}
 
-		return TypeCombinator::intersect($type, $objectType)->toBoolean()->isTrue()->yes();
+		return TypeCombinator::intersect($type, new ObjectWithoutClassType())->toBoolean()->isTrue()->yes();
 	}
 
 	private function containsCall(Expr $expr): bool

tests/PHPStan/Rules/Comparison/UnnecessaryTernaryOperatorRuleTest.php

@@ -87,15 +87,15 @@ public function testRule(): void
 			],
 			[
 				'Short ternary operator ?: is unnecessary because it always results in $foo.',
-				151,
+				162,
 			],
 			[
 				'Ternary operator is unnecessary because it always results in $s.',
-				190,
+				201,
 			],
 			[
 				'Ternary operator is unnecessary because it always results in $foo.',
-				195,
+				206,
 			],
 		]);
 	}
@@ -143,15 +143,15 @@ public function testRuleWithoutTreatingPhpDocTypesAsCertain(): void
 			],
 			[
 				'Short ternary operator ?: is unnecessary because it always results in $foo.',
-				151,
+				162,
 			],
 			[
 				'Ternary operator is unnecessary because it always results in $s.',
-				190,
+				201,
 			],
 			[
 				'Ternary operator is unnecessary because it always results in $foo.',
-				195,
+				206,
 			],
 		]);
 	}

tests/PHPStan/Rules/Comparison/data/unnecessary-ternary.php

@@ -143,6 +143,17 @@ function strlenOfString(string|false $blob): int
 	return $blob !== false ? strlen($blob) : 0;
 }
 
+/** @return null */
+function maybeSideEffects()
+{
+	return null;
+}
+
+function callWithMaybeSideEffects(?Foo $foo): ?Foo
+{
+	return $foo ?: maybeSideEffects();
+}
+
 trait FooTrait
 {
 
@@ -219,3 +230,15 @@ public function simpleXmlNot(?\SimpleXMLElement $xml): ?\SimpleXMLElement
 	}
 
 }
+
+class ConstantCondition
+{
+
+	public function alwaysFalse(): int
+	{
+		// TernaryOperatorConstantConditionRule reports this
+		$i = 0;
+		return $i ?: 0;
+	}
+
+}