docs: Improve comments

src/bin/cargo/commands/fix.rs

@@ -67,8 +67,6 @@ pub fn exec(gctx: &mut GlobalContext, args: &ArgMatches) -> CliResult {
         args.get_one::<String>("profile").map(String::as_str),
         Some("test")
     );
-    let mode = CompileMode::Check { test };
-
     // Unlike other commands default `cargo fix` to all targets to fix as much
     // code as we can.
     let root_manifest = args.root_manifest(gctx)?;
@@ -79,7 +77,12 @@ pub fn exec(gctx: &mut GlobalContext, args: &ArgMatches) -> CliResult {
     let lockfile_path = args.lockfile_path(gctx)?;
     ws.set_requested_lockfile_path(lockfile_path.clone());
 
-    let mut opts = args.compile_options(gctx, mode, Some(&ws), ProfileChecking::LegacyTestOnly)?;
+    let mut opts = args.compile_options(
+        gctx,
+        CompileMode::Check { test },
+        Some(&ws),
+        ProfileChecking::LegacyTestOnly,
+    )?;
 
     if !opts.filter.is_specific() {
         // cargo fix with no target selection implies `--all-targets`.

src/cargo/ops/fix.rs

@@ -4,27 +4,27 @@
 //! diagnostics with suggested fixes that can be applied to the files on the
 //! filesystem, and validate that those changes didn't break anything.
 //!
-//! Cargo begins by launching a `LockServer` thread in the background to
+//! Cargo begins by launching a [`LockServer`] thread in the background to
 //! listen for network connections to coordinate locking when multiple targets
 //! are built simultaneously. It ensures each package has only one fix running
 //! at once.
 //!
-//! The `RustfixDiagnosticServer` is launched in a background thread (in
+//! The [`RustfixDiagnosticServer`] is launched in a background thread (in
 //! `JobQueue`) to listen for network connections to coordinate displaying
 //! messages to the user on the console (so that multiple processes don't try
 //! to print at the same time).
 //!
 //! Cargo begins a normal `cargo check` operation with itself set as a proxy
-//! for rustc by setting `primary_unit_rustc` in the build config. When
+//! for rustc by setting [BuildConfig::primary_unit_rustc] in the build config. When
 //! cargo launches rustc to check a crate, it is actually launching itself.
-//! The `FIX_ENV_INTERNAL` environment variable is set so that cargo knows it is in
-//! fix-proxy-mode.
+//! The `FIX_ENV_INTERNAL` environment variable is set to the value of the [`LockServer`]'s
+//! address so that cargo knows it is in fix-proxy-mode.
 //!
 //! Each proxied cargo-as-rustc detects it is in fix-proxy-mode (via `FIX_ENV_INTERNAL`
 //! environment variable in `main`) and does the following:
 //!
-//! - Acquire a lock from the `LockServer` from the master cargo process.
-//! - Launches the real rustc (`rustfix_and_fix`), looking at the JSON output
+//! - Acquire a lock from the [`LockServer`] from the master cargo process.
+//! - Launches the real rustc ([`rustfix_and_fix`]), looking at the JSON output
 //!   for suggested fixes.
 //! - Uses the `rustfix` crate to apply the suggestions to the files on the
 //!   file system.
@@ -35,6 +35,8 @@
 //!   applied cleanly, rustc is run again to verify the suggestions didn't
 //!   break anything. The change will be backed out if it fails (unless
 //!   `--broken-code` is used).
+//!
+//! [BuildConfig]: crate::core::compiler::BuildConfig
 
 use std::collections::{BTreeSet, HashMap, HashSet};
 use std::ffi::OsString;