Passing `--no-doc` to ./x.py test causes panic_abort tests to fail

[jacob-hughes]

Running ./x.py test --stage 1 --no-doc on the latest version of nightly (#80114) causes the test suite to crash with the following error:

error: building tests with panic=abort is not supported without `-Zpanic_abort_tests`

error: aborting due to previous error

error: could not compile `panic_abort`

This seems like a bug in the bootstrapper where --no-doc causes tests to be erroneously compiled with the abort panic strategy, since tests pass as expected with ./x.py test --stage 1 (--no-doc omitted)

This error can be also triggered with a subset of the test suite by running ./x.py test library/panic_abort --stage 1 --no-doc

[jyn514]

This also reproduces with --stage 0.

[jyn514]

I think the issue is that bootstrap passes --lib", "--bins", "--examples", "--tests", "--benches" to the target, and that isn't valid for this target. This fixes the issue:

diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 965d1162145..2b6266be7ee 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -1887,7 +1887,7 @@ fn run(self, builder: &Builder<'_>) {
                 cargo.arg("--doc");
             }
             DocTests::No => {
-                cargo.args(&["--lib", "--bins", "--examples", "--tests", "--benches"]);
+                cargo.args(&["--bins", "--examples", "--tests", "--benches"]);
             }
             DocTests::Yes => {}
         }

I've suggested "--no-doc" (and similar things) to the cargo team before, but I don't think there's currently an RFC for it.

[jyn514]

Also it seems like a bug that cargo tries to compile unit tests for the crate even though they're disabled:

rust/library/panic_abort/Cargo.toml

Line 11 in b52769b

test = false

@ehuss do you happen to know if there's an open issue for that?

[ehuss]

For now, that is intentional behavior, so that you can override the setting via the command-line. I feel like it is a toss-up which behavior is better, but for now it's working as intended.