cargo-fix.txt

CARGO-FIX(1)

NAME
       cargo-fix - Automatically fix lint warnings reported by rustc

SYNOPSIS
       cargo fix [options]

DESCRIPTION
       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>.

   Edition migration
       The cargo fix subcommand can also be used to migrate a package from one
       edition
       <https://doc.rust-lang.org/edition-guide/editions/transitioning-an-existing-project-to-a-new-edition.html>
       to the next. The general procedure is:

       1. Run 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.

       2. Modify Cargo.toml to set the edition field
          <https://doc.rust-lang.org/cargo/reference/manifest.html#the-edition-field>
          to the new edition.

       3. Run your project tests to verify that everything still works. If new
          warnings are issued, you may want to consider running 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.

OPTIONS
   Fix options
       --broken-code
           Fix code even if it already has compiler errors. This is useful if
           cargo fix fails to apply the changes. It will apply the changes and
           leave the broken code in the working directory for you to inspect
           and manually fix.

       --edition
           Apply changes that will update the code to the next edition. This
           will not update the edition in the Cargo.toml manifest, which must
           be updated manually after cargo fix --edition has finished.

       --edition-idioms
           Apply suggestions that will update code to the preferred style for
           the current edition.

       --allow-no-vcs
           Fix code even if a VCS was not detected.

       --allow-dirty
           Fix code even if the working directory has changes.

       --allow-staged
           Fix code even if the working directory has staged changes.

   Package Selection
       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.

       -p spec..., --package spec...
           Fix only the specified packages. See cargo-pkgid(1) for the SPEC
           format. This flag may be specified multiple times and supports
           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
           pattern.

       --workspace
           Fix all members in the workspace.

       --all
           Deprecated alias for --workspace.

       --exclude SPEC...
           Exclude the specified packages. Must be used in conjunction with the
           --workspace flag. This flag may be specified multiple times and
           supports 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 pattern.

   Target Selection
       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.

       --lib
           Fix the package's library.

       --bin name...
           Fix the specified binary. This flag may be specified multiple times
           and supports common Unix glob patterns.

       --bins
           Fix all binary targets.

       --example name...
           Fix the specified example. This flag may be specified multiple times
           and supports common Unix glob patterns.

       --examples
           Fix all example targets.

       --test name...
           Fix the specified integration test. This flag may be specified
           multiple times and supports common Unix glob patterns.

       --tests
           Fix all targets in test mode that have the test = true manifest flag
           set. By default this includes the library and binaries built as
           unittests, and integration tests. Be aware that this will also build
           any required dependencies, so the lib target may be built twice
           (once as a unittest, and once as a dependency for binaries,
           integration tests, etc.). Targets may be enabled or disabled by
           setting the test flag in the manifest settings for the target.

       --bench name...
           Fix the specified benchmark. This flag may be specified multiple
           times and supports common Unix glob patterns.

       --benches
           Fix all targets in benchmark mode that have the bench = true
           manifest flag set. By default this includes the library and binaries
           built as benchmarks, and bench targets. Be aware that this will also
           build any required dependencies, so the lib target may be built
           twice (once as a benchmark, and once as a dependency for binaries,
           benchmarks, etc.). Targets may be enabled or disabled by setting the
           bench flag in the manifest settings for the target.

       --all-targets
           Fix all targets. This is equivalent to specifying --lib --bins
           --tests --benches --examples.

   Feature Selection
       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
       <https://doc.rust-lang.org/cargo/reference/features.html#command-line-feature-options>
       for more details.

       -F features, --features features
           Space or comma separated list of features to activate. Features of
           workspace members may be enabled with package-name/feature-name
           syntax. This flag may be specified multiple times, which enables all
           specified features.

       --all-features
           Activate all available features of all selected packages.

       --no-default-features
           Do not activate the default feature of the selected packages.

   Compilation Options
       --target triple
           Fix for the given architecture. The default is the host
           architecture. The general format of the triple is
           <arch><sub>-<vendor>-<sys>-<abi>. Run rustc --print target-list for
           a list of supported targets.

           This may also be specified with the build.target config value
           <https://doc.rust-lang.org/cargo/reference/config.html>.

           Note that specifying this flag makes Cargo run in a different mode
           where the target artifacts are placed in a separate directory. See
           the build cache
           <https://doc.rust-lang.org/cargo/guide/build-cache.html>
           documentation for more details.

       -r, --release
           Fix optimized artifacts with the release profile. See also the
           --profile option for choosing a specific profile by name.

       --profile name
           Fix with the given profile.

           As a special case, specifying the test profile will also enable
           checking in test mode which will enable checking tests and enable
           the test cfg option. See rustc tests
           <https://doc.rust-lang.org/rustc/tests/index.html> for more detail.

           See the the reference
           <https://doc.rust-lang.org/cargo/reference/profiles.html> for more
           details on profiles.

       --ignore-rust-version
           Fix the target even if the selected Rust compiler is older than the
           required Rust version as configured in the project's rust-version
           field.

       --timings=fmts
           Output information how long each compilation takes, and track
           concurrency information over time. Accepts an optional
           comma-separated list of output formats; --timings without an
           argument will default to --timings=html. Specifying an output format
           (rather than the default) is unstable and requires
           -Zunstable-options. Valid output formats:

           o  html: Write a human-readable file cargo-timing.html to the
              target/cargo-timings directory with a report of the compilation.
              Also write a report to the same directory with a timestamp in the
              filename if you want to look at older runs. HTML output is
              suitable for human consumption only, and does not provide
              machine-readable timing data.

           o  json (unstable, requires -Zunstable-options): Emit
              machine-readable JSON information about timing information.

   Output Options
       --target-dir directory
           Directory for all generated artifacts and intermediate files. May
           also be specified with the CARGO_TARGET_DIR environment variable, or
           the build.target-dir config value
           <https://doc.rust-lang.org/cargo/reference/config.html>. Defaults to
           target in the root of the workspace.

   Display Options
       -v, --verbose
           Use verbose output. May be specified twice for "very verbose" output
           which includes extra output such as dependency warnings and build
           script output. May also be specified with the term.verbose config
           value <https://doc.rust-lang.org/cargo/reference/config.html>.

       -q, --quiet
           Do not print cargo log messages. May also be specified with the
           term.quiet config value
           <https://doc.rust-lang.org/cargo/reference/config.html>.

       --color when
           Control when colored output is used. Valid values:

           o  auto (default): Automatically detect if color support is
              available on the terminal.

           o  always: Always display colors.

           o  never: Never display colors.

           May also be specified with the term.color config value
           <https://doc.rust-lang.org/cargo/reference/config.html>.

       --message-format fmt
           The output format for diagnostic messages. Can be specified multiple
           times and consists of comma-separated values. Valid values:

           o  human (default): Display in a human-readable text format.
              Conflicts with short and json.

           o  short: Emit shorter, human-readable text messages. Conflicts with
              human and json.

           o  json: Emit JSON messages to stdout. See the reference
              <https://doc.rust-lang.org/cargo/reference/external-tools.html#json-messages>
              for more details. Conflicts with human and short.

           o  json-diagnostic-short: Ensure the rendered field of JSON messages
              contains the "short" rendering from rustc. Cannot be used with
              human or short.

           o  json-diagnostic-rendered-ansi: Ensure the rendered field of JSON
              messages contains embedded ANSI color codes for respecting
              rustc's default color scheme. Cannot be used with human or short.

           o  json-render-diagnostics: Instruct Cargo to not include rustc
              diagnostics in in JSON messages printed, but instead Cargo itself
              should render the JSON diagnostics coming from rustc. Cargo's own
              JSON diagnostics and others coming from rustc are still emitted.
              Cannot be used with human or short.

   Manifest Options
       --manifest-path path
           Path to the Cargo.toml file. By default, Cargo searches for the
           Cargo.toml file in the current directory or any parent directory.

       --frozen, --locked
           Either of these flags requires that the Cargo.lock file is
           up-to-date. If the lock file is missing, or it needs to be updated,
           Cargo will exit with an error. The --frozen flag also prevents Cargo
           from attempting to access the network to determine if it is
           out-of-date.

           These may be used in environments where you want to assert that the
           Cargo.lock file is up-to-date (such as a CI build) or want to avoid
           network access.

       --offline
           Prevents Cargo from accessing the network for any reason. Without
           this flag, Cargo will stop with an error if it needs to access the
           network and the network is not available. With this flag, Cargo will
           attempt to proceed without the network if possible.

           Beware that this may result in different dependency resolution than
           online mode. Cargo will restrict itself to crates that are
           downloaded locally, even if there might be a newer version as
           indicated in the local copy of the index. See the cargo-fetch(1)
           command to download dependencies before going offline.

           May also be specified with the net.offline config value
           <https://doc.rust-lang.org/cargo/reference/config.html>.

   Common Options
       +toolchain
           If Cargo has been installed with rustup, and the first argument to
           cargo begins with +, it will be interpreted as a rustup toolchain
           name (such as +stable or +nightly). See the rustup documentation
           <https://rust-lang.github.io/rustup/overrides.html> for more
           information about how toolchain overrides work.

       --config KEY=VALUE
           Overrides a Cargo configuration value.

       -h, --help
           Prints help information.

       -Z flag
           Unstable (nightly-only) flags to Cargo. Run cargo -Z help for
           details.

   Miscellaneous Options
       -j N, --jobs N
           Number of parallel jobs to run. May also be specified with the
           build.jobs config value
           <https://doc.rust-lang.org/cargo/reference/config.html>. Defaults to
           the number of CPUs.

       --keep-going
           Build as many crates in the dependency graph as possible, rather
           than aborting the build on the first one that fails to build.
           Unstable, requires -Zunstable-options.

ENVIRONMENT
       See the reference
       <https://doc.rust-lang.org/cargo/reference/environment-variables.html>
       for details on environment variables that Cargo reads.

EXIT STATUS
       o  0: Cargo succeeded.

       o  101: Cargo failed to complete.

EXAMPLES
       1. Apply compiler suggestions to the local package:

              cargo fix

       2. Update a package to prepare it for the next edition:

              cargo fix --edition

       3. Apply suggested idioms for the current edition:

              cargo fix --edition-idioms

SEE ALSO
       cargo(1), cargo-check(1)