initial working version of cargo fix --clippy

src/bin/cargo/commands/fix.rs

@@ -72,6 +72,20 @@ pub fn cli() -> App {
                 .long("allow-staged")
                 .help("Fix code even if the working directory has staged changes"),
         )
+        .arg(
+            Arg::with_name("clippy")
+                .long("clippy")
+                .help("Get fix suggestions from clippy instead of check")
+                .hidden(true),
+        )
+        .arg(
+            Arg::with_name("clippy-arg")
+                .long("clippy-arg")
+                .help("Args to pass through to clippy, implies --clippy")
+                .hidden(true)
+                .multiple(true)
+                .number_of_values(1),
+        )
         .after_help(
             "\
 This Cargo subcommand will automatically take rustc's suggestions from
@@ -125,6 +139,16 @@ pub fn exec(config: &mut Config, args: &ArgMatches<'_>) -> CliResult {
     // code as we can.
     let mut opts = args.compile_options(config, mode, Some(&ws))?;
 
+    let clippy_args = args.values_of_lossy("clippy-args");
+    let use_clippy = args.is_present("clippy") || clippy_args.is_some();
+
+    if use_clippy && !config.cli_unstable().unstable_options {
+        return Err(failure::format_err!(
+            "`cargo fix --clippy` is unstable, pass `-Z unstable-options` to enable it"
+        )
+        .into());
+    }
+
     if let CompileFilter::Default { .. } = opts.filter {
         opts.filter = CompileFilter::Only {
             all_targets: true,
@@ -146,6 +170,8 @@ pub fn exec(config: &mut Config, args: &ArgMatches<'_>) -> CliResult {
             allow_no_vcs: args.is_present("allow-no-vcs"),
             allow_staged: args.is_present("allow-staged"),
             broken_code: args.is_present("broken-code"),
+            use_clippy,
+            clippy_args,
         },
     )?;
     Ok(())

src/cargo/ops/fix.rs

@@ -63,6 +63,9 @@ const BROKEN_CODE_ENV: &str = "__CARGO_FIX_BROKEN_CODE";
 const PREPARE_FOR_ENV: &str = "__CARGO_FIX_PREPARE_FOR";
 const EDITION_ENV: &str = "__CARGO_FIX_EDITION";
 const IDIOMS_ENV: &str = "__CARGO_FIX_IDIOMS";
+const CLIPPY_FIX_ENV: &str = "__CARGO_FIX_CLIPPY_PLZ";
+const CLIPPY_FIX_ARGS: &str = "__CARGO_FIX_CLIPPY_ARGS";
+const CLIPPY_PASSHTHROUGH_SEP: &str = "__CLIPPYSEP__";
 
 pub struct FixOptions<'a> {
     pub edition: bool,
@@ -73,6 +76,8 @@ pub struct FixOptions<'a> {
     pub allow_no_vcs: bool,
     pub allow_staged: bool,
     pub broken_code: bool,
+    pub use_clippy: bool,
+    pub clippy_args: Option<Vec<String>>,
 }
 
 pub fn fix(ws: &Workspace<'_>, opts: &mut FixOptions<'_>) -> CargoResult<()> {
@@ -99,6 +104,14 @@ pub fn fix(ws: &Workspace<'_>, opts: &mut FixOptions<'_>) -> CargoResult<()> {
         wrapper.env(IDIOMS_ENV, "1");
     }
 
+    if opts.use_clippy {
+        wrapper.env(CLIPPY_FIX_ENV, "1");
+    }
+
+    if let Some(clippy_args) = &opts.clippy_args {
+        wrapper.env(CLIPPY_FIX_ARGS, clippy_args.join(CLIPPY_PASSHTHROUGH_SEP));
+    }
+
     *opts
         .compile_opts
         .build_config
@@ -385,6 +398,7 @@ fn rustfix_and_fix(
 
     let mut cmd = Command::new(rustc);
     cmd.arg("--error-format=json");
+
     args.apply(&mut cmd);
     let output = cmd
         .output()
@@ -565,6 +579,7 @@ struct FixArgs {
     other: Vec<OsString>,
     primary_package: bool,
     rustc: Option<PathBuf>,
+    clippy_args: Vec<String>,
 }
 
 enum PrepareFor {
@@ -582,7 +597,19 @@ impl Default for PrepareFor {
 impl FixArgs {
     fn get() -> FixArgs {
         let mut ret = FixArgs::default();
-        ret.rustc = env::args_os().nth(1).map(PathBuf::from);
+        if env::var(CLIPPY_FIX_ENV).is_ok() {
+            ret.rustc = Some(PathBuf::from("clippy-driver"));
+        } else {
+            ret.rustc = env::args_os().nth(1).map(PathBuf::from);
+        }
+
+        if let Ok(clippy_args) = env::var(CLIPPY_FIX_ARGS) {
+            ret.clippy_args = clippy_args
+                .split(CLIPPY_PASSHTHROUGH_SEP)
+                .map(ToString::to_string)
+                .collect();
+        }
+
         for arg in env::args_os().skip(2) {
             let path = PathBuf::from(arg);
             if path.extension().and_then(|s| s.to_str()) == Some("rs") && path.exists() {
@@ -608,6 +635,7 @@ impl FixArgs {
         } else if env::var(EDITION_ENV).is_ok() {
             ret.prepare_for_edition = PrepareFor::Next;
         }
+
         ret.idioms = env::var(IDIOMS_ENV).is_ok();
         ret.primary_package = env::var("CARGO_PRIMARY_PACKAGE").is_ok();
         ret
@@ -617,6 +645,11 @@ impl FixArgs {
         if let Some(path) = &self.file {
             cmd.arg(path);
         }
+
+        if !self.clippy_args.is_empty() {
+            cmd.args(&self.clippy_args);
+        }
+
         cmd.args(&self.other).arg("--cap-lints=warn");
         if let Some(edition) = &self.enabled_edition {
             cmd.arg("--edition").arg(edition);