Preserve precision when passing BigDecimal or BigFloat to sprintf %i#15808
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straight-shoota merged 3 commits intocrystal-lang:masterfrom May 23, 2025
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This is the only type in the standard library where `#to_i32` is already defined but `#to_i` isn't. This makes `BigRational` suspectible to precision loss when passed to `sprintf` `%i` (see also #15808), since `BigRational#to_i32` currently delegates to `#to_f64` instead of `#to_big_i`. However this is still an improvement over the current situation where `BigRational` isn't supported by `sprintf` at all.
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When
String::Formatterformats a non-integer for integer specifiers such as%d, it calls#to_ion that value to reuse the implementation forInt32, meaningBigDecimals andBigFloats outsideInt32's range will raise anOverflowError. Fortunately,BigIntis already compatible withsprintf, so they could delegate toBigIntinstead ofInt32.This may look similar to #15203, but the fix there is not as simple as delegating to
#to_big_f, because that also loses precision.