topdown: fix format_int precision loss for integers larger than 64 bits#8857
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Synvoya wants to merge 2 commits into
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topdown: fix format_int precision loss for integers larger than 64 bits#8857Synvoya wants to merge 2 commits into
format_int precision loss for integers larger than 64 bits#8857Synvoya wants to merge 2 commits into
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format_int routed integers through a 64-bit-mantissa big.Float, corrupting any value above ~2^64 (disagreeing with sprintf). Format integer inputs through an exact big.Int; fractional inputs keep float truncation. Signed-off-by: Synvoya <16019863+Synvoya@users.noreply.github.com>
WASM's format_int cannot represent integers larger than 64 bits (get uint failed), the same limitation already tracked for integer literals (open-policy-agent#3711). Add the new golden case to the WASM e2e exceptions so it runs under Go (where the fix applies) but is skipped under WASM. Signed-off-by: Synvoya <16019863+Synvoya@users.noreply.github.com>
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Description
format_int(x, base)corrupts integers that need more than 64 bits of precision, in every base. It routes the value throughbuiltins.NumberToFloat(abig.Floatwith a 64-bit mantissa) thenf.Int(), so any integer above ~2^64 is rounded before formatting:sprintf("%x", [18446744073709551617])returns the correct10000000000000001, so two builtins disagree on the same exact-integer value.Fix
Format integer inputs through an exact
big.Int(mirroringbuiltinSprintf). Fractional/exponent inputs still fall through to the existing float-truncation path, soformat_int(15.9, 16) == "f"andformat_int(-15.9, 16) == "-f"are unchanged.Test
Added a golden case covering a >2^64 integer in bases 2/8/10/16, negatives, and the fractional-truncation cases. Full
go test ./v1/topdown/passes (900+ existing string golden cases, no regressions).