Constexpr evaluator underflow / overflow handling for + and -

[BafS]

I have a type error bug (similar to #5505) when using binary shifts

Psalm version: v4.7.3

Error

Uncaught TypeError: Argument 2 passed to Psalm\Type::getInt() must be of the type int or null, float given, called in phar:///.../vendor/psalm/phar/psalm.phar/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php on line 162 and defined in phar:///.../vendor/psalm/phar/psalm.phar/src/Psalm/Type.php:129

psalm.xml

<?xml version="1.0"?>
<psalm
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="https://getpsalm.org/schema/config"
    xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
    xmlns:xi="http://www.w3.org/2001/XInclude"
>
    <projectFiles>
        <file name="bug-psalm.php" />
    </projectFiles>
</psalm>

bug-psalm.php

<?php

const MASK = (1 << 63) - (1 << 20);

[psalm-github-bot]

Hey @BafS, can you reproduce the issue on https://psalm.dev ?

[BafS]

Yes, https://psalm.dev/r/b5c187cf0c

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/b5c187cf0c

<?php

const MASK = (1 << 63) - (1 << 20);

Psalm encountered an internal error:

/vendor/vimeo/psalm/src/Psalm/Type.php: Argument 2 passed to Psalm\Type::getInt() must be of the type int or null, float given, called in /vendor/vimeo/psalm/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php on line 314

[weirdan]

The code handling Plus and Minus should be fixed to handle float results, the way it's already done for Pow and Mul:

psalm/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php

Lines 311 to 340 in cf6a4e7

	if ($parent instanceof PhpParser\Node\Expr\BinaryOp\Plus) {
	$calculated_type = Type::getInt(false, $left_type_part->value + $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Minus) {
	$calculated_type = Type::getInt(false, $left_type_part->value - $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Mod) {
	$calculated_type = Type::getInt(false, $left_type_part->value % $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Mul) {
	$result = $left_type_part->value * $right_type_part->value;
	if ($result <= PHP_INT_MAX) {
	$calculated_type = Type::getInt(false, $result);
	} else {
	$calculated_type = Type::getFloat($result);
	}
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\Pow) {
	$result = $left_type_part->value ** $right_type_part->value;
	if ($result <= PHP_INT_MAX) {
	$calculated_type = Type::getInt(false, $result);
	} else {
	$calculated_type = Type::getFloat($result);
	}
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\BitwiseOr) {
	$calculated_type = Type::getInt(false, $left_type_part->value | $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\BitwiseAnd) {
	$calculated_type = Type::getInt(false, $left_type_part->value & $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\BitwiseXor) {
	$calculated_type = Type::getInt(false, $left_type_part->value ^ $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\ShiftLeft) {
	$calculated_type = Type::getInt(false, $left_type_part->value << $right_type_part->value);
	} elseif ($parent instanceof PhpParser\Node\Expr\BinaryOp\ShiftRight) {
	$calculated_type = Type::getInt(false, $left_type_part->value >> $right_type_part->value);

[BafS]

Pow is not completely fixed btw, you need to check PHP_INT_MAX but PHP_INT_MIN too.

See https://psalm.dev/r/e4949e1737

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/e4949e1737

<?php

2 ** 63;

Psalm encountered an internal error:

/vendor/vimeo/psalm/src/Psalm/Type.php: Argument 2 passed to Psalm\Type::getInt() must be of the type int or null, float given, called in /vendor/vimeo/psalm/src/Psalm/Internal/Analyzer/Statements/Expression/BinaryOp/NonDivArithmeticOpAnalyzer.php on line 327