fix(ops): correct error messages for cargo fix --broken-code

crates/cargo-util-terminal/src/shell.rs

@@ -233,6 +233,14 @@ impl Shell {
         self.print_report(report, false)
     }
 
+    /// Prints a cyan 'help' message.
+    pub fn help<T: fmt::Display>(&mut self, message: T) -> CargoResult<()> {
+        let report = &[annotate_snippets::Group::with_title(
+            annotate_snippets::Level::HELP.secondary_title(message.to_string()),
+        )];
+        self.print_report(report, false)
+    }
+
     /// Updates the verbosity of the shell.
     pub fn set_verbosity(&mut self, verbosity: Verbosity) {
         self.verbosity = verbosity;

src/cargo/ops/fix/mod.rs

@@ -791,10 +791,26 @@ pub fn fix_exec_rustc(gctx: &GlobalContext, lock_addr: &str) -> CargoResult<()>
 
     // If there were any fixes, let the user know that there was a failure
     // attempting to apply them, and to ask for a bug report.
-    //
-    // FIXME: The error message here is not correct with --broken-code.
-    //        https://github.com/rust-lang/cargo/issues/10955
     if fixes.files.is_empty() {
+        if !fixes.last_output.status.success() {
+            if allow_broken_code {
+                gctx.shell()
+                    .warn("no fixes were suggested because the code is already broken")?;
+                gctx.shell().note(
+                    "cargo fix requires code that compiles successfully to apply automatic fixes",
+                )?;
+                gctx.shell()
+                    .note("the broken code was saved due to `--broken-code`")?;
+            } else {
+                gctx.shell()
+                    .warn("no fixes were suggested because the code is already broken")?;
+                gctx.shell().note(
+                    "cargo fix requires code that compiles successfully to apply automatic fixes",
+                )?;
+                gctx.shell()
+                    .help("use `--broken-code` to save partial progress")?;
+            }
+        }
         // No fixes were available. Display whatever errors happened.
         emit_output(&fixes.last_output)?;
         exit_with(fixes.last_output.status);
@@ -814,6 +830,7 @@ pub fn fix_exec_rustc(gctx: &GlobalContext, lock_addr: &str) -> CargoResult<()>
             krate,
             &fixes.last_output.stderr,
             fixes.last_output.status,
+            allow_broken_code,
         )?;
         // Display the diagnostics that appeared at the start, before the
         // fixes failed. This can help with diagnosing which suggestions
@@ -1171,6 +1188,7 @@ fn log_failed_fix(
     krate: Option<String>,
     stderr: &[u8],
     status: ExitStatus,
+    allow_broken_code: bool,
 ) -> CargoResult<()> {
     let stderr = str::from_utf8(stderr).context("failed to parse rustc stderr as utf-8")?;
 
@@ -1205,6 +1223,7 @@ fn log_failed_fix(
         krate,
         errors,
         abnormal_exit,
+        allow_broken_code,
     }
     .post(gctx)?;
 

src/cargo/util/diagnostic_server.rs

@@ -43,6 +43,7 @@ pub enum Message {
         krate: Option<String>,
         errors: Vec<String>,
         abnormal_exit: Option<String>,
+        allow_broken_code: bool,
     },
     ReplaceFailed {
         file: String,
@@ -146,6 +147,7 @@ impl<'a> DiagnosticPrinter<'a> {
                 krate,
                 errors,
                 abnormal_exit,
+                allow_broken_code,
             } => {
                 let to_crate = if let Some(ref krate) = *krate {
                     format!(" to crate `{krate}`",)
@@ -160,28 +162,36 @@ impl<'a> DiagnosticPrinter<'a> {
                     None
                 };
 
-                let report = &[
-                    Level::ERROR
-                        .secondary_title(format!("errors present after applying fixes{to_crate}"))
-                        .elements(files.iter().map(|f| Origin::path(f)))
-                        .elements(
-                            cause_message
-                                .into_iter()
-                                .map(|err| Level::ERROR.with_name("cause").message(err)),
-                        )
-                        .elements(abnormal_exit.iter().map(|exit| {
-                            Level::ERROR
-                                .with_name("cause")
-                                .message(format!("rustc exited abnormally: {exit}"))
-                        })),
-                    gen_please_report_this_bug_group(issue_link),
-                    gen_suggest_broken_code_group(),
-                    Group::with_title(
-                        Level::NOTE.secondary_title("original diagnostics will follow:"),
-                    ),
-                ];
+                let report = &[Level::ERROR
+                    .secondary_title(format!("errors present after applying fixes{to_crate}"))
+                    .elements(files.iter().map(|f| Origin::path(f)))
+                    .elements(
+                        cause_message
+                            .into_iter()
+                            .map(|err| Level::ERROR.with_name("cause").message(err)),
+                    )
+                    .elements(abnormal_exit.iter().map(|exit| {
+                        Level::ERROR
+                            .with_name("cause")
+                            .message(format!("rustc exited abnormally: {exit}"))
+                    }))];
+
+                let mut report = report.to_vec();
+
+                if *allow_broken_code {
+                    report.push(Group::with_title(Level::WARNING.secondary_title(
+                        "fixes were applied but the code still does not compile; partially-fixed code was saved due to `--broken-code`"
+                    )));
+                } else {
+                    report.push(gen_please_report_this_bug_group(issue_link));
+                    report.push(gen_suggest_broken_code_group());
+                }
 
-                self.gctx.shell().print_report(report, false)?;
+                report.push(Group::with_title(
+                    Level::NOTE.secondary_title("original diagnostics will follow:"),
+                ));
+
+                self.gctx.shell().print_report(&report, false)?;
                 Ok(())
             }
             Message::EditionAlreadyEnabled { message, edition } => {

tests/testsuite/fix.rs

@@ -1435,8 +1435,7 @@ fn fix_to_broken_code() {
   = cause: thread 'main' ([..]) panicked at src/main.rs:23:29:
            explicit panic
            [NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
-[HELP] to report this as a bug, open an issue at https://github.com/rust-lang/rust/issues, quoting the full output of this command
-[HELP] to possibly apply more fixes, pass in the `--broken-code` flag
+[WARNING] fixes were applied but the code still does not compile; partially-fixed code was saved due to `--broken-code`
 [NOTE] original diagnostics will follow:
 ...
 
@@ -2381,6 +2380,9 @@ fn fix_in_rust_src() {
         .with_status(101)
         .with_stderr_data(str![[r#"
 [CHECKING] foo v0.0.0 ([ROOT]/foo)
+[WARNING] no fixes were suggested because the code is already broken
+[NOTE] cargo fix requires code that compiles successfully to apply automatic fixes
+[NOTE] the broken code was saved due to `--broken-code`
 error[E0308]: mismatched types
  --> lib.rs:5:9
   |

tests/testsuite/fix_n_times.rs

@@ -532,6 +532,9 @@ fn starts_with_error() {
         },
         str![[r#"
 [CHECKING] foo v0.0.1 ([ROOT]/foo)
+[WARNING] no fixes were suggested because the code is already broken
+[NOTE] cargo fix requires code that compiles successfully to apply automatic fixes
+[HELP] use `--broken-code` to save partial progress
 rustc fix shim error count=1
 [ERROR] could not compile `foo` (lib) due to 1 previous error
 
@@ -550,6 +553,9 @@ fn broken_code_no_suggestions() {
         },
         str![[r#"
 [CHECKING] foo v0.0.1 ([ROOT]/foo)
+[WARNING] no fixes were suggested because the code is already broken
+[NOTE] cargo fix requires code that compiles successfully to apply automatic fixes
+[NOTE] the broken code was saved due to `--broken-code`
 rustc fix shim error count=1
 [ERROR] could not compile `foo` (lib) due to 1 previous error
 
@@ -571,8 +577,7 @@ fn broken_code_one_suggestion() {
 [ERROR] errors present after applying fixes to crate `foo`
  --> src/lib.rs
   = cause: rustc fix shim error count=2
-[HELP] to report this as a bug, open an issue at https://github.com/rust-lang/rust/issues, quoting the full output of this command
-[HELP] to possibly apply more fixes, pass in the `--broken-code` flag
+[WARNING] fixes were applied but the code still does not compile; partially-fixed code was saved due to `--broken-code`
 [NOTE] original diagnostics will follow:
 rustc fix shim comment 1
 rustc fix shim error count=2