cargo-fix --- Automatically fix lint warnings reported by rustc
cargo fix
[options]
This Cargo subcommand will automatically take rustc's suggestions from diagnostics like warnings and apply them to your source code. This is intended to help automate tasks that rustc itself already knows how to tell you to fix!
Executing cargo fix
will under the hood execute cargo-check(1). Any warnings applicable to your crate will be automatically fixed (if possible) and all remaining warnings will be displayed when the check process is finished. For example if you'd like to apply all fixes to the current package, you can run:
cargo fix
which behaves the same as cargo check --all-targets
.
cargo fix
is only capable of fixing code that is normally compiled with cargo check
. If code is conditionally enabled with optional features, you will need to enable those features for that code to be analyzed:
cargo fix --features foo
Similarly, other cfg
expressions like platform-specific code will need to pass --target
to fix code for the given target.
cargo fix --target x86_64-pc-windows-gnu
If you encounter any problems with cargo fix
or otherwise have any questions or feature requests please don't hesitate to file an issue at https://github.com/rust-lang/cargo.
The cargo fix
subcommand can also be used to migrate a package from one edition to the next. The general procedure is:
cargo fix --edition
. Consider also using the --all-features
flag if your project has multiple features. You may also want to run cargo fix --edition
multiple times with different --target
flags if your project has platform-specific code gated by cfg
attributes.Cargo.toml
to set the edition field to the new edition.cargo fix
again (without the --edition
flag) to apply any suggestions given by the compiler.And hopefully that's it! Just keep in mind of the caveats mentioned above that cargo fix
cannot update code for inactive features or cfg
expressions. Also, in some rare cases the compiler is unable to automatically migrate all code to the new edition, and this may require manual changes after building with the new edition.
By default, when no package selection options are given, the packages selected depend on the selected manifest file (based on the current working directory if --manifest-path
is not given). If the manifest is the root of a workspace then the workspaces default members are selected, otherwise only the package defined by the manifest will be selected.
The default members of a workspace can be set explicitly with the workspace.default-members
key in the root manifest. If this is not set, a virtual workspace will include all workspace members (equivalent to passing --workspace
), and a non-virtual workspace will include only the root crate itself.
When no target selection options are given, cargo fix
will fix all targets (--all-targets
implied). Binaries are skipped if they have required-features
that are missing.
Passing target selection flags will fix only the specified targets.
Note that --bin
, --example
, --test
and --bench
flags also support common Unix glob patterns like *
, ?
and []
. However, to avoid your shell accidentally expanding glob patterns before Cargo handles them, you must use single quotes or double quotes around each glob pattern.
The feature flags allow you to control which features are enabled. When no feature options are given, the default
feature is activated for every selected package.
See the features documentation for more details.
See the reference for details on environment variables that Cargo reads.
0
: Cargo succeeded.101
: Cargo failed to complete.Apply compiler suggestions to the local package:
cargo fix
Update a package to prepare it for the next edition:
cargo fix --edition
Apply suggested idioms for the current edition:
cargo fix --edition-idioms