fix(data): grow small open-addressing tables past their initial capacity - #366
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DoubleHashing.grownSize computed the next backing-array length as (int) (currentLength * 1.2), which truncates to the same value for the smallest tables: 3 -> 3 and 4 -> 4. A map created with a small initial size (e.g. new OpenAddressingMap<>(3), floor is 3) that fills up then resizes to the same length, so put() can never find a free slot and recurses forever, throwing StackOverflowError. Both OpenAddressingMap and IntKeyOpenAddressingMap share this growth policy and are affected. Floor the growth at currentLength + 1 so the table always gets strictly larger. Add regression tests: grownSize growth for small lengths, and filling a size-3 map of each type well past its initial capacity. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01CxcEdnagvEwNXcUi3QBxTc
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DoubleHashing.grownSize computed the next backing-array length as
(int) (currentLength * 1.2), which truncates to the same value for the
smallest tables: 3 -> 3 and 4 -> 4. A map created with a small initial
size (e.g. new OpenAddressingMap<>(3), floor is 3) that fills up then
resizes to the same length, so put() can never find a free slot and
recurses forever, throwing StackOverflowError. Both OpenAddressingMap
and IntKeyOpenAddressingMap share this growth policy and are affected.
Floor the growth at currentLength + 1 so the table always gets strictly
larger. Add regression tests: grownSize growth for small lengths, and
filling a size-3 map of each type well past its initial capacity.
Co-Authored-By: Claude Opus 4.8 noreply@anthropic.com
Claude-Session: https://claude.ai/code/session_01CxcEdnagvEwNXcUi3QBxTc