InterleaveShortest: don't overflow size_hint lower bound#1102
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c-tonneslan wants to merge 1 commit into
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InterleaveShortest: don't overflow size_hint lower bound#1102c-tonneslan wants to merge 1 commit into
c-tonneslan wants to merge 1 commit into
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The combined lower bound was computed with saturating_mul, so could already be at usize::MAX, and then the unchecked +1 would panic in debug builds when both halves of the interleave reported large lower bounds (e.g. an Iterator::take(usize::MAX) interleaved with iter::repeat). Switch to saturating_add. Closes rust-itertools#1068. Signed-off-by: Charlie Tonneslan <cst0520@gmail.com>
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combined_loweris computed withsaturating_mul, so it can already sit atusize::MAX. The next line then does an uncheckedcombined_lower + 1when the current half has a larger lower bound, which panics in debug builds. Hit it with something likeiter::repeat(0).take(usize::MAX).interleave_shortest(iter::repeat(1)).Swap the
+forsaturating_add.Closes #1068.