feat(closure): closure parameter type narrowing from call-site literals

phpunit/code/closure-param-reassign.php

@@ -0,0 +1,52 @@
+<?php
+/**
+ * Isolated fixture: a Closure parameter written by the body.
+ *
+ * PHP allows re-assigning a parameter to any other type, so a parameter
+ * narrowed from its call sites would truncate the value (float stored into an
+ * int) or fail to compile. Only a parameter the body never writes to may be
+ * narrowed.
+ */
+
+function reassignToString(): void
+{
+    $fn = function ($rwStr) {
+        $rwStr = "str";
+        return $rwStr;
+    };
+    var_dump($fn(42));
+}
+
+function reassignToFloat(): void
+{
+    $fn = function ($rwFloat) {
+        $rwFloat = 1.5;
+        return $rwFloat;
+    };
+    var_dump($fn(42));
+}
+
+function incrementParam(): void
+{
+    $fn = function ($rwInc) {
+        $rwInc++;
+        return $rwInc;
+    };
+    var_dump($fn(42));
+}
+
+function writeThroughArrayDim(): void
+{
+    $fn = function ($rwDim) {
+        $rwDim[] = 9;
+        return $rwDim;
+    };
+    var_dump($fn([1, 2]));
+}
+
+// A parameter the body only reads still narrows.
+function untouchedParamStillNarrows(): void
+{
+    $fn = fn($roKeep) => $roKeep + 1;
+    var_dump($fn(42));
+}

phpunit/code/closure-param-type-class.php

@@ -0,0 +1,9 @@
+<?php
+class MyClass
+{
+    public function method(): int
+    {
+        $fn = fn(int $x) => $x + 1;
+        return $fn(42);
+    }
+}

phpunit/code/closure-param-type-varint.php

@@ -0,0 +1,123 @@
+<?php
+/**
+ * Test fixture for closure parameter type narrowing in varint_types mode.
+ *
+ * In varint mode, inferred int locals are stored in php::Var (not php::Int)
+ * to retain Zend integer widening semantics. Closure parameters with type
+ * declarations like int $param expect php::Int, but call-site variables are
+ * php::Var. The compiler must handle this type mismatch correctly.
+ */
+
+use varint_types;
+
+// --- Type declarations work correctly in varint mode ---
+
+function varintTypeDeclInt(int $vd1): int
+{
+    $fn = fn(int $p) => $p + 1;
+    $i = 42;
+    return $fn($i);
+}
+
+function varintTypeDeclFloat(float $vd2): float
+{
+    $fn = fn(float $p) => $p * 2.0;
+    $f = 3.14;
+    return $fn($f);
+}
+
+// --- Inferred types in call sites ---
+
+function varintInferredInt(): int
+{
+    $fn = fn(int $vi1) => $vi1 + 1;
+    $a = 10;
+    $b = 5;
+    return $fn($a + $b);
+}
+
+function varintInferredIntSub(): int
+{
+    $fn = fn(int $vis1) => $vis1 - 1;
+    $a = 20;
+    $b = 3;
+    return $fn($a - $b);
+}
+
+function varintInferredIntMul(): int
+{
+    $fn = fn(int $vim1) => $vim1 * 2;
+    $a = 7;
+    $b = 4;
+    return $fn($a * $b);
+}
+
+function varintInferredIntMod(): int
+{
+    $fn = fn(int $vimod1) => $vimod1 + 1;
+    $a = 10;
+    $b = 3;
+    return $fn($a % $b);
+}
+
+function varintInferredIntShiftLeft(): int
+{
+    $fn = fn(int $visl1) => $visl1 + 1;
+    $a = 3;
+    $b = 2;
+    return $fn($a << $b);
+}
+
+function varintInferredIntShiftRight(): int
+{
+    $fn = fn(int $visr1) => $visr1 + 1;
+    $a = 16;
+    $b = 2;
+    return $fn($a >> $b);
+}
+
+// --- Mixed type scenarios ---
+
+function varintMixedParams(): array
+{
+    $fn = fn(int $vmx1, float $vmx2) => [$vmx1, $vmx2];
+    $i = 42;
+    $f = 3.14;
+    return $fn($i, $f);
+}
+
+function varintBinaryPow(): int
+{
+    $fn = fn(int $vbp1) => $vbp1 + 1;
+    $a = 2;
+    $b = 3;
+    return $fn($a ** $b);
+}
+
+// --- Float division in varint mode (non-constant → Variant) ---
+
+function varintFloatDiv(): void
+{
+    $fn = fn($vfdiv1) => $vfdiv1;
+    $a = 3.14;
+    $b = 2;
+    var_dump($fn($a / $b));
+}
+
+// --- Main function for testing ---
+
+function main(): void
+{
+    echo "varintTypeDeclInt: " . varintTypeDeclInt(0) . "\n";
+    echo "varintTypeDeclFloat: " . varintTypeDeclFloat(0.0) . "\n";
+    echo "varintInferredInt: " . varintInferredInt() . "\n";
+    echo "varintInferredIntSub: " . varintInferredIntSub() . "\n";
+    echo "varintInferredIntMul: " . varintInferredIntMul() . "\n";
+    echo "varintInferredIntMod: " . varintInferredIntMod() . "\n";
+    echo "varintInferredIntShiftLeft: " . varintInferredIntShiftLeft() . "\n";
+    echo "varintInferredIntShiftRight: " . varintInferredIntShiftRight() . "\n";
+    $mixed = varintMixedParams();
+    echo "varintMixedParams: [" . $mixed[0] . ", " . $mixed[1] . "]\n";
+    echo "varintBinaryPow: " . varintBinaryPow() . "\n";
+    varintFloatDiv();
+}