Handle BcMath\Number operators for simple cases #3787
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The result changed because getSortedTypes is called somewhere which sorts the exponent's union type and leads to a change in the result.
| @@ -395,4 +395,9 @@ public function substrReturnFalseInsteadOfEmptyString(): bool | |||
| return $this->versionId < 80000; | |||
| } | |||
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| public function supportsBcMathNumberOperatorOverloading(): bool | |||
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I copied this from the original PR. But I'm not sure whether it's correct. I assume that the reason we even need this is because earlier PHP versions might use a polyfill (which wouldn't have the operators overloaded). But PHP 8.4 can also use a polyfill, because bcmath is an optional extension.
| assertType('int<4, 27>|int<16, 81>', pow($range, $x)); | ||
| assertType('int<4, 27>|int<16, 81>', $range ** $x); | ||
| assertType('int<4, 81>', pow($range, $x)); | ||
| assertType('int<4, 81>', $range ** $x); | ||
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| assertType('int<4, 27>|int<16, 64>', pow($x, $range)); | ||
| assertType('int<4, 27>|int<16, 64>', $x ** $range); | ||
| assertType('int<4, 64>', pow($x, $range)); | ||
| assertType('int<4, 64>', $x ** $range); |
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This is a result of UnionType::getSortedTypes being called. I haven't looked into it, but I guess it's a bug in TypeCombinator::union, because the result of a union shouldn't depend on the order of parameters.
EDIT: I had to fix it, because it broke the test on PHP <8.4 due to the extension only running on 8.4 and above.
| assertType('true', $a or $b); | ||
| } | ||
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| public function bcVsNever(Number $a): void |
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There's a bunch of inconsistencies in how never type is handled. I assume that all of these operations should result in *NEVER*, but I'm ignoring it for this PR.
It was fixed by fixing union(int, int<null, -1>, int<1, null>) = int.
| IntegerRangeType::fromInterval(8, 27), | ||
| ], | ||
| IntegerRangeType::class, | ||
| 'int<4, 81>', |
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Was: int<4, 27>|int<16, 81>.
| IntegerRangeType::fromInterval(16, 81), | ||
| ], | ||
| IntegerRangeType::class, | ||
| 'int<4, 81>', |
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Was: int<4, 7>|int<8, 81> (testUnionInversed)
| IntegerRangeType::fromInterval(1, null), | ||
| ], | ||
| IntegerType::class, | ||
| 'int', |
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Was: int|int<min, -1> (testUnionInversed)
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This pull request has been marked as ready for review. |
Partially fixes: phpstan/phpstan#12099
Fixes: phpstan/phpstan#7937, phpstan/phpstan#8555
It's loosely based on #3660
Here is a demonstration of how the operators behave with various types: https://3v4l.org/jYX5J#v8.4.3
I skipped the complicated stuff. The main issue is unions. IMO it's too difficult to handle unions correctly in the extension. It would probably make more sense for PHPStan to handle the unions itself and offload only non-unions to extensions (e.g.
X|int + X|floatneeds to know whatint + floatis).I also ignored a few preexisting bugs/inconsistencies (null and never types). They can be solved later.