Auto merge of #86098 - pietroalbini:test-stable, r=Mark-Simulacrum

Add the x86_64-gnu-stable builder

During the 1.52 release process we had to deal with some commits that passed the test suite on the nightly branch but failed on the beta or stable branch. In that case it was due to some UI tests including the channel name in the output, but other changes might also be dependent on the channel.

This commit adds a new CI job that runs the Linux x86_64 test suite with the stable branch, ensuring nightly changes also work as stable. To ensure the new job works the following other changes are present:

* The `ui-fulldeps/session-derive-errors.rs` test has been disabled on beta and stable, which required adding support for `// ignore-{channel}` and `// only-{channel}`.
* The `rustdoc/intra-doc/field.rs` has been fixed.

r? `@Mark-Simulacrum`
fixes https://github.com/rust-lang/release-team/issues/11

1 files changed, 11 insertions, 0 deletions

diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index 343091cb779..e704071e401 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -407,6 +407,17 @@ jobs:
           - name: x86_64-gnu
             <<: *job-linux-xl
 
+          # This job ensures commits landing on nightly still pass the full
+          # test suite on the stable channel. There are some UI tests that
+          # depend on the channel being built (for example if they include the
+          # channel name on the output), and this builder prevents landing
+          # changes that would result in broken builds after a promotion.
+          - name: x86_64-gnu-stable
+            env:
+              IMAGE: x86_64-gnu
+              RUST_CI_OVERRIDE_RELEASE_CHANNEL: stable
+            <<: *job-linux-xl
+
           - name: x86_64-gnu-aux
             <<: *job-linux-xl