Explains, in response to review, that the toggle gate mirrors
StringType::toArrayKey() and is required to avoid the bug phpstan#4671
false positive (isset on a string-keyed array with a (string) $int offset).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

- `IntegerType::toString()` now returns `string&decimal-int-string` instead of `string&lowercase-string&uppercase-string&numeric-string`. Casting an int to string always yields the canonical decimal representation (no leading `+`/zeros, no exponent), which is exactly `decimal-int-string` (a subtype of numeric/lowercase/uppercase, so this is strictly more precise).
- `IntegerRangeType::toString()` mirrors the same change for the non-finite branches, keeping `non-falsy-string` for ranges that exclude `0`.
- `(string) bool` and `(string) constant-int` were already precise (`''|'1'` / constant strings), so no change was needed there.
- Fixed an adjacent inconsistency: `IntersectionType::toArrayKey()` coerced `decimal-int-string` to `int` unconditionally, ignoring `ReportUnsafeArrayStringKeyCastingToggle`, while `StringType::toArrayKey()` respects it. This made `[$decimalIntString => 1]` infer `array<int, 1>` by default even though `[$plainString => 1]` stays `array<string, 1>`, and reintroduced the bug phpstan#4671 false positive (`isset($stringKeyedArray[(string) $int])`). The decimal branch now stays a string key unless the toggle is `PREVENT`, matching `StringType`.
- Updated `decimal-int-string.php` to reflect the corrected lenient default (`[$s => 1]` is `array<decimal-int-string, 1>`), and refreshed the expected types in the cast/array-key inference tests that now report the more precise `decimal-int-string`.

Explains, in response to review, that the toggle gate mirrors
StringType::toArrayKey() and is required to avoid the bug phpstan#4671
false positive (isset on a string-keyed array with a (string) $int offset).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

- `IntegerType::toString()` now returns `string&decimal-int-string` instead of `string&lowercase-string&uppercase-string&numeric-string`. Casting an int to string always yields the canonical decimal representation (no leading `+`/zeros, no exponent), which is exactly `decimal-int-string` (a subtype of numeric/lowercase/uppercase, so this is strictly more precise).
- `IntegerRangeType::toString()` mirrors the same change for the non-finite branches, keeping `non-falsy-string` for ranges that exclude `0`.
- `(string) bool` and `(string) constant-int` were already precise (`''|'1'` / constant strings), so no change was needed there.
- Fixed an adjacent inconsistency: `IntersectionType::toArrayKey()` coerced `decimal-int-string` to `int` unconditionally, ignoring `ReportUnsafeArrayStringKeyCastingToggle`, while `StringType::toArrayKey()` respects it. This made `[$decimalIntString => 1]` infer `array<int, 1>` by default even though `[$plainString => 1]` stays `array<string, 1>`, and reintroduced the bug phpstan#4671 false positive (`isset($stringKeyedArray[(string) $int])`). The decimal branch now stays a string key unless the toggle is `PREVENT`, matching `StringType`.
- Updated `decimal-int-string.php` to reflect the corrected lenient default (`[$s => 1]` is `array<decimal-int-string, 1>`), and refreshed the expected types in the cast/array-key inference tests that now report the more precise `decimal-int-string`.

Explains, in response to review, that the toggle gate mirrors
StringType::toArrayKey() and is required to avoid the bug phpstan#4671
false positive (isset on a string-keyed array with a (string) $int offset).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

The toArrayKey() coercion of decimal-int-string keys is an unrelated
concern tracked separately in phpstan/phpstan#14758, so it is dropped
from this PR. Removing the special case lets decimal-int-string fall
through to the numeric-string branch (it is a numeric-string), yielding
int|decimal-int-string just like any other numeric string. This keeps
the bug phpstan#4671 isset regression test green without implementing the
toggle-gated precision behavior, which belongs in #14758.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

- `IntegerType::toString()` now returns `string&decimal-int-string` instead of `string&lowercase-string&uppercase-string&numeric-string`. Casting an int to string always yields the canonical decimal representation (no leading `+`/zeros, no exponent), which is exactly `decimal-int-string` (a subtype of numeric/lowercase/uppercase, so this is strictly more precise).
- `IntegerRangeType::toString()` mirrors the same change for the non-finite branches, keeping `non-falsy-string` for ranges that exclude `0`.
- `(string) bool` and `(string) constant-int` were already precise (`''|'1'` / constant strings), so no change was needed there.
- Fixed an adjacent inconsistency: `IntersectionType::toArrayKey()` coerced `decimal-int-string` to `int` unconditionally, ignoring `ReportUnsafeArrayStringKeyCastingToggle`, while `StringType::toArrayKey()` respects it. This made `[$decimalIntString => 1]` infer `array<int, 1>` by default even though `[$plainString => 1]` stays `array<string, 1>`, and reintroduced the bug phpstan#4671 false positive (`isset($stringKeyedArray[(string) $int])`). The decimal branch now stays a string key unless the toggle is `PREVENT`, matching `StringType`.
- Updated `decimal-int-string.php` to reflect the corrected lenient default (`[$s => 1]` is `array<decimal-int-string, 1>`), and refreshed the expected types in the cast/array-key inference tests that now report the more precise `decimal-int-string`.

Explains, in response to review, that the toggle gate mirrors
StringType::toArrayKey() and is required to avoid the bug phpstan#4671
false positive (isset on a string-keyed array with a (string) $int offset).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

The toArrayKey() coercion of decimal-int-string keys is an unrelated
concern tracked separately in phpstan/phpstan#14758, so it is dropped
from this PR. Removing the special case lets decimal-int-string fall
through to the numeric-string branch (it is a numeric-string), yielding
int|decimal-int-string just like any other numeric string. This keeps
the bug phpstan#4671 isset regression test green without implementing the
toggle-gated precision behavior, which belongs in #14758.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

- `IntegerType::toString()` now returns `string&decimal-int-string` instead of `string&lowercase-string&uppercase-string&numeric-string`. Casting an int to string always yields the canonical decimal representation (no leading `+`/zeros, no exponent), which is exactly `decimal-int-string` (a subtype of numeric/lowercase/uppercase, so this is strictly more precise).
- `IntegerRangeType::toString()` mirrors the same change for the non-finite branches, keeping `non-falsy-string` for ranges that exclude `0`.
- `(string) bool` and `(string) constant-int` were already precise (`''|'1'` / constant strings), so no change was needed there.
- Fixed an adjacent inconsistency: `IntersectionType::toArrayKey()` coerced `decimal-int-string` to `int` unconditionally, ignoring `ReportUnsafeArrayStringKeyCastingToggle`, while `StringType::toArrayKey()` respects it. This made `[$decimalIntString => 1]` infer `array<int, 1>` by default even though `[$plainString => 1]` stays `array<string, 1>`, and reintroduced the bug phpstan#4671 false positive (`isset($stringKeyedArray[(string) $int])`). The decimal branch now stays a string key unless the toggle is `PREVENT`, matching `StringType`.
- Updated `decimal-int-string.php` to reflect the corrected lenient default (`[$s => 1]` is `array<decimal-int-string, 1>`), and refreshed the expected types in the cast/array-key inference tests that now report the more precise `decimal-int-string`.

Explains, in response to review, that the toggle gate mirrors
StringType::toArrayKey() and is required to avoid the bug phpstan#4671
false positive (isset on a string-keyed array with a (string) $int offset).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

The toArrayKey() coercion of decimal-int-string keys is an unrelated
concern tracked separately in phpstan/phpstan#14758, so it is dropped
from this PR. Removing the special case lets decimal-int-string fall
through to the numeric-string branch (it is a numeric-string), yielding
int|decimal-int-string just like any other numeric string. This keeps
the bug phpstan#4671 isset regression test green without implementing the
toggle-gated precision behavior, which belongs in #14758.

Co-Authored-By: Claude Opus 4.8 <[email protected]>