[`mut_mut`]: Fix duplicate diags #16344

	name: Clippy Dev Test

	on:
	push:
	branches:
	- auto
	- try
	pull_request:
	# Only run on paths, that get checked by the clippy_dev tool
	paths:
	- 'CHANGELOG.md'
	- 'README.md'
	- '**.stderr'
	- '**.rs'

	env:
	RUST_BACKTRACE: 1
	CARGO_INCREMENTAL: 0

	jobs:
	clippy_dev:
	runs-on: ubuntu-latest

	steps:
	# Setup
	- name: Checkout
	uses: actions/checkout@v4

	# Run
	- name: Build
	run: cargo build --features deny-warnings
	working-directory: clippy_dev

	- name: Test update_lints
	run: cargo dev update_lints --check

	- name: Test fmt
	run: cargo dev fmt --check

	- name: Test cargo dev new lint
	run: \|
	cargo dev new_lint --name new_early_pass --pass early
	cargo dev new_lint --name new_late_pass --pass late
	cargo check
	git reset --hard HEAD

	# These jobs doesn't actually test anything, but they're only used to tell
	# bors the build completed, as there is no practical way to detect when a
	# workflow is successful listening to webhooks only.
	#
	# ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!

	end-success:
	name: bors dev test finished
	if: github.event.pusher.name == 'bors' && success()
	runs-on: ubuntu-latest
	needs: [clippy_dev]

	steps:
	- name: Mark the job as successful
	run: exit 0

	end-failure:
	name: bors dev test finished
	if: github.event.pusher.name == 'bors' && (failure() \|\| cancelled())
	runs-on: ubuntu-latest
	needs: [clippy_dev]

	steps:
	- name: Mark the job as a failure
	run: exit 1

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