Eliminate all use of hash-based collections from crate_universe #1737
+30
−31
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UebelAndre
approved these changes
Jan 1, 2023
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This is necessary together with #1736 to keep the generated BUILD files deterministic. Iterating a hashmap or hashset in hash order is a common source of nondeterminism in code generators (based on my experience with proc macros).
I haven't looked into which of the hashmaps changed in this diff are correctly used. It's possible to use a hashmap correctly, if all we do with them is lookups, not iteration. But it's simple enough to just not use hash-based containers entirely and never have hash order nondeterminism problems.