x.py test src/tools/clippy shouldn't build rustdoc

[jyn514]

I tried this code: x.py test src/tools/clippy
I expected to see this happen: bootstrap builds the compiler and clippy
Instead, this happened: bootstrap builds the compiler, clippy, and rustdoc

Meta

git merge-base HEAD origin/master is 69e1d22

[ehuss]

This is normal for running x.py test, since it runs doctests on the libraries.

You can pass --no-doc to skip building rustdoc.

[jyn514]

@ehuss do you know why it uses the in-tree rustdoc instead of the bootstrap compiler? I was using --stage 1.

[ehuss]

The tests run with the in-tree rustc (stage1), which will also require using the in-tree rustdoc (stage1). Using stage0 rustdoc would be testing against an older version, and I don't think would necessarily work.

I'd imagine nobody considered it when clippy was brought in-tree, since that is all determined at a low level inside rustbuild.

However, taking a closer look, it appears that clippy doesn't have any doctests, so I imagine defaulting that to off would be reasonable (assuming clippy never intends to add doctests in the future). It looks like rustbuild does not make that easy since it is a property of the Builder, so it would require some work to support that.

[jyn514]

The tests run with the in-tree rustc (stage1), which will also require using the in-tree rustdoc (stage1). Using stage0 rustdoc would be testing against an older version, and I don't think would necessarily work.

Ok, I see the issue - this is using the "test with stage 1" meaning, not "build stage 1 and test it" like I thought (the first builds compiler/ twice, the second only once). test --stage 0 src/tools/clippy seems to be broken because of weird things with clippy's copy of compiletest: #78717.

However, taking a closer look, it appears that clippy doesn't have any doctests,

I see some in clippy_lints:

rust/src/tools/clippy/clippy_lints/src/methods/mod.rs

Line 98 in 1284da3

/// ```rust

[ehuss]

x.py test src/tools/clippy does not run any tests on clippy_lints. It only tests the integration tests in the tests directory. rust-lang/rust only does a subset of clippy's full suite of tests.