Sort @standard_token_types for reproducible compilation - #75
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@standard_token_types captures Map.keys/1 of a 70-key map at compile time. On modern Erlang/OTP the iteration order of maps with more than 32 keys depends on the atom-table indexes of the keys, which vary between VM instances (atom creation order is racy under the parallel compiler). The unsorted key list is embedded as a literal in Elixir.Makeup.Token.Utils.beam, making it the one module in the ex_doc escript that differs between two builds. Sorting the keys makes the literal deterministic; no caller depends on the order. See https://reproducible-builds.org/ for why this is good. This patch was done while working on reproducible builds for openSUSE.
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@standard_token_typescaptures Map.keys/1 of a 70-key map at compile time. On modern Erlang/OTP the iteration order of maps with more than 32 keys depends on the atom-table indexes of the keys, which vary between VM instances (atom creation order is racy under the parallel compiler). The unsorted key list is embedded as a literal in Elixir.Makeup.Token.Utils.beam, making it the one module in the ex_doc escript that differs between two builds.Sorting the keys makes the literal deterministic; no caller depends on the order.
This helps with erlang/otp#4417
See https://reproducible-builds.org/ for why this is good.
This patch was done while working on reproducible builds for openSUSE.