Force `-runs=1` when invoking in repro mode
@@ -171,6 +171,15 @@ impl<'a> LibFuzzer<'a> {
// good input, which libfuzzer works as we expect.
let mut cmd = self.build_command(None, None, None).await?;
+
+ // Override any arg of the form `-runs=<N>` (last occurrence wins).
+ // In this command invocation, we only ever want to test inputs once.
+ //
+ // Assumes that the presence of an `-args` option was an iteration limit meant
+ // for fuzzing mode. We are only mutating the args of a local `Command`, so the
+ // command used by the `fuzz()` method will still receive the iteration limit.
+ cmd.arg("-runs=1");
+
cmd.arg(&input);
let result = cmd
