Heads up! This PR modifies the following files:

• @bholley: components/style/Cargo.toml, components/style/stylesheets.rs, components/style/lib.rs, components/style/values.rs, components/style/media_queries.rs, components/style/properties.mako.rs, components/style/font_face.rs

@bors-servo r+

📌 Commit cac6a13 has been approved by SimonSapin

⌛ Testing commit cac6a13 with merge 8d7f3be...

💔 Test failed - mac-dev-unit

failed to select a version for `selectors` (required by `util`):
all possible versions conflict with previously selected versions of `selectors`
  version 0.2.2 in use by selectors v0.2.2
  possible versions to select: 0.2.3

I can’t reproduce locally and don’t understand how this happens with 0.2.3 in the lock file, but I’ll try to bump the requirement in Cargo.toml.

@bors-servo r+

📌 Commit 529d7d9 has been approved by SimonSapin

⌛ Testing commit 529d7d9 with merge 0c11512...

💔 Test failed - mac-dev-unit

I haven’t managed to reproduce this issue on the builder. This worked fine:

ssh servo-mac3.servo.org
su servo
cd /Users/servo/buildbot/slave/mac-dev-unit/build
CARGO_HOME=/Users/servo/.cargo SERVO_CACHE_DIR=/Users/servo/.servo ./mach build-geckolib

Retry just in case something has changed, and also to make buildbot spin up EC2 builders so that I can investigate another issue.

@bors-servo retry

⌛ Testing commit 529d7d9 with merge e4522b9...

Oh oops I realize now when I said "I'm not sure other machines are failing" I meant to say "I'm not sure why the other machines are failing", sorry if that caused any confusion!

This looks like you just need to rebase the branch, the Cargo.lock patch applies but there has been changes in the meantime which means that it's basically a corrupt Cargo.lock

This makes sense. When trying to reproduce I was using the branch, never a merge of the branch with master. I’ll try that tomorrow.

Here is what I did:

• Checkout this PR’s branch, geckolib builds fine
• Fetch upstream and rebase unto upstream/master. Now I can reproduce the issue.
• Run ./mach cargo-update -p selectors. The same error message shows up for ports/geckolib.
• Look at ports/geckolib/Cargo.lock. It declares a dependency on selectors 0.2.2, but there is not [[package]] section for it. Change it manually to 0.2.3.
• Build again, the problem seems to be fixed.

@bors-servo r+

So the moral of the story is:

• CI doesn’t test your PR, it tests a merge of your PR into master. Thanks Alex for pointing this out! When something only happens on CI, rebasing may help.
• A git merge of branches that both have changes to Cargo.lock can result in an inconsistent Cargo.lock file. I’ll file an issue about making Cargo more robust in that situation.

📌 Commit 0013fce has been approved by SimonSapin

⌛ Testing commit 0013fce with merge fe0fc90...

💔 Test failed - linux-dev

Fixed duplicate dependency introduced in the rebase.

@bors-servo r+

📌 Commit 6fd46b5 has been approved by SimonSapin

Cargo bug: rust-lang/cargo#2302. This needs at least a better error message, if not automatic resolution.

⌛ Testing commit 6fd46b5 with merge 1ba1fb0...

☀️ Test successful - android, gonk, linux-dev, linux-rel, mac-dev-unit, mac-rel-css, mac-rel-wpt