Running Fuzzers

Run only fuzzers:

bash

ast fuzz
ast fuzz parser
ast fuzz parser --runs 10000 --seed 42
ast fuzz parser --runs 1.5x
ast fuzz parser --runs +10%

Run tests and fuzzers together:

bash

ast test --fuzz
ast test --fuzz --fuzz-runs 10000 --fuzz-seed 42
ast test --fuzz --fuzz-runs +100000

Useful Flags

--runs <value>
--seed <n>
--jobs <n>
--build-jobs <n>
--run-jobs <n>
--mode <name[,name...]>

<value> can be:

an absolute run count like 500
a multiplier like 1.5x
an additive percentage like +10%
an additive integer like +100000

Notes

fuzz targets currently build as bindings
xfuzz(...) registers a skipped fuzz target
CLI run overrides apply to each fuzzer's effective base count, including fuzzers that set their own third fuzz(..., operations) argument
fuzz results are summarized separately from normal test totals