Make -Ztrack-diagnostics emit like a note

compiler/rustc_errors/src/emitter.rs

@@ -1392,6 +1392,7 @@ impl HumanEmitter {
         label: &str,
         override_style: Option<Style>,
     ) -> usize {
+        let line_offset = buffer.num_lines().saturating_sub(1);
         // The extra 5 ` ` is padding that's always needed to align to the `note: `:
         //
         //   error: message
@@ -1447,12 +1448,20 @@ impl HumanEmitter {
                 for (i, line) in lines.iter().enumerate() {
                     if i != 0 {
                         line_number += 1;
-                        buffer.append(line_number, &padding, Style::NoStyle);
+                        buffer.append(line_number + line_offset, &padding, Style::NoStyle);
                     }
-                    buffer.append(line_number, line, style_or_override(*style, override_style));
+                    buffer.append(
+                        line_number + line_offset,
+                        line,
+                        style_or_override(*style, override_style),
+                    );
                 }
             } else {
-                buffer.append(line_number, text, style_or_override(*style, override_style));
+                buffer.append(
+                    line_number + line_offset,
+                    text,
+                    style_or_override(*style, override_style),
+                );
             }
         }
         line_number
@@ -1468,40 +1477,21 @@ impl HumanEmitter {
         level: &Level,
         max_line_num_len: usize,
         is_secondary: bool,
-        emitted_at: Option<&DiagLocation>,
         is_cont: bool,
     ) -> io::Result<()> {
         let mut buffer = StyledBuffer::new();
 
         if !msp.has_primary_spans() && !msp.has_span_labels() && is_secondary && !self.short_message
         {
-            // This is a secondary message with no span info
-            for _ in 0..max_line_num_len {
-                buffer.prepend(0, " ", Style::NoStyle);
-            }
-            self.draw_note_separator(&mut buffer, 0, max_line_num_len + 1, is_cont);
-            if *level != Level::FailureNote {
-                buffer.append(0, level.to_str(), Style::MainHeaderMsg);
-                buffer.append(0, ": ", Style::NoStyle);
-            }
-            let printed_lines =
-                self.msgs_to_buffer(&mut buffer, msgs, args, max_line_num_len, "note", None);
-            if is_cont && matches!(self.theme, OutputTheme::Unicode) {
-                // There's another note after this one, associated to the subwindow above.
-                // We write additional vertical lines to join them:
-                //   ╭▸ test.rs:3:3
-                //   │
-                // 3 │   code
-                //   │   ━━━━
-                //   │
-                //   ├ note: foo
-                //   │       bar
-                //   ╰ note: foo
-                //           bar
-                for i in 1..=printed_lines {
-                    self.draw_col_separator_no_space(&mut buffer, i, max_line_num_len + 1);
-                }
-            }
+            self.draw_secondary_message(
+                &mut buffer,
+                msgs,
+                args,
+                0,
+                level,
+                max_line_num_len,
+                is_cont,
+            );
         } else {
             let mut label_width = 0;
             // The failure note level itself does not provide any useful diagnostic information
@@ -1978,12 +1968,6 @@ impl HumanEmitter {
             trace!("buffer: {:#?}", buffer.render());
         }
 
-        if let Some(tracked) = emitted_at {
-            let track = format!("-Ztrack-diagnostics: created at {tracked}");
-            let len = buffer.num_lines();
-            buffer.append(len, &track, Style::NoStyle);
-        }
-
         // final step: take our styled buffer, render it, then output it
         emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
 
@@ -2495,34 +2479,56 @@ impl HumanEmitter {
             level,
             max_line_num_len,
             false,
-            emitted_at,
-            !children.is_empty()
-                || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden),
+            emitted_at.is_some()
+                || (!children.is_empty()
+                    || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden)),
         ) {
             Ok(()) => {
-                if !children.is_empty()
+                let mut buffer = StyledBuffer::new();
+                let primary_span = span.primary_span().unwrap_or_default();
+                if let (Some(tracked), false) = (emitted_at, primary_span.is_dummy()) {
+                    if !self.short_message {
+                        self.draw_col_separator_no_space(&mut buffer, 0, max_line_num_len + 1);
+                        let track = format!("-Ztrack-diagnostics: created at {tracked}");
+
+                        self.draw_secondary_message(
+                            &mut buffer,
+                            &[(DiagMessage::Str(Cow::Owned(track)), Style::NoStyle)],
+                            args,
+                            1,
+                            &Level::Note,
+                            max_line_num_len,
+                            children.first().is_some_and(|c| c.span.primary_spans().is_empty()),
+                        );
+                    }
+                } else if !children.is_empty()
                     || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden)
                 {
-                    let mut buffer = StyledBuffer::new();
+                    let line_offest = buffer.num_lines();
                     if !self.short_message {
                         if let Some(child) = children.iter().next()
                             && child.span.primary_spans().is_empty()
                         {
                             // We'll continue the vertical bar to point into the next note.
-                            self.draw_col_separator_no_space(&mut buffer, 0, max_line_num_len + 1);
+                            self.draw_col_separator_no_space(
+                                &mut buffer,
+                                line_offest,
+                                max_line_num_len + 1,
+                            );
                         } else {
                             // We'll close the vertical bar to visually end the code window.
-                            self.draw_col_separator_end(&mut buffer, 0, max_line_num_len + 1);
+                            self.draw_col_separator_end(
+                                &mut buffer,
+                                line_offest,
+                                max_line_num_len + 1,
+                            );
                         }
                     }
-                    if let Err(e) = emit_to_destination(
-                        &buffer.render(),
-                        level,
-                        &mut self.dst,
-                        self.short_message,
-                    ) {
-                        panic!("failed to emit error: {e}")
-                    }
+                }
+                if let Err(e) =
+                    emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)
+                {
+                    panic!("failed to emit error: {e}")
                 }
                 if !self.short_message {
                     for (i, child) in children.iter().enumerate() {
@@ -2541,7 +2547,6 @@ impl HumanEmitter {
                             &child.level,
                             max_line_num_len,
                             true,
-                            None,
                             !should_close,
                         ) {
                             panic!("failed to emit error: {err}");
@@ -2561,7 +2566,6 @@ impl HumanEmitter {
                                     &Level::Help,
                                     max_line_num_len,
                                     true,
-                                    None,
                                     // FIXME: this needs to account for the suggestion type,
                                     //        some don't take any space.
                                     i + 1 != suggestions.len(),
@@ -2740,6 +2744,44 @@ impl HumanEmitter {
         *row_num += 1;
     }
 
+    fn draw_secondary_message(
+        &self,
+        buffer: &mut StyledBuffer,
+        msgs: &[(DiagMessage, Style)],
+        args: &FluentArgs<'_>,
+        line: usize,
+        level: &Level,
+        max_line_num_len: usize,
+        is_cont: bool,
+    ) {
+        // This is a secondary message with no sphan info
+        for _ in 0..max_line_num_len {
+            buffer.prepend(line, " ", Style::NoStyle);
+        }
+        self.draw_note_separator(buffer, line, max_line_num_len + 1, is_cont);
+        if *level != Level::FailureNote {
+            buffer.append(line, level.to_str(), Style::MainHeaderMsg);
+            buffer.append(line, ": ", Style::NoStyle);
+        }
+        let printed_lines = self.msgs_to_buffer(buffer, msgs, args, max_line_num_len, "note", None);
+        if is_cont && matches!(self.theme, OutputTheme::Unicode) {
+            // There's another note after this one, associated to the subwindow above.
+            // We write additional vertical lines to join them:
+            //   ╭▸ test.rs:3:3
+            //   │
+            // 3 │   code
+            //   │   ━━━━
+            //   │
+            //   ├ note: foo
+            //   │       bar
+            //   ╰ note: foo
+            //           bar
+            for i in 1 + line..=printed_lines + line {
+                self.draw_col_separator_no_space(buffer, i, max_line_num_len + 1);
+            }
+        }
+    }
+
     fn underline(&self, is_primary: bool) -> UnderlineParts {
         //               X0 Y0
         // label_start > ┯━━━━ < underline

src/tools/clippy/tests/ui/track-diagnostics.stderr

@@ -3,7 +3,8 @@ error[E0308]: mismatched types
    |
 LL | const S: A = B;
    |              ^ expected `A`, found `B`
--Ztrack-diagnostics: created at compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs:LL:CC
 
 error: aborting due to 1 previous error
 

tests/rustdoc-ui/track-diagnostics.stderr

@@ -3,7 +3,8 @@ error[E0308]: mismatched types
    |
 LL | pub const S: A = B;
    |                  ^ expected `A`, found `B`
--Ztrack-diagnostics: created at compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_trait_selection/src/error_reporting/infer/mod.rs:LL:CC
 
 error: aborting due to 1 previous error
 

tests/ui/track-diagnostics/track.stderr

@@ -3,22 +3,24 @@ error[E0425]: cannot find value `rust` in this scope
    |
 LL |     break rust
    |           ^^^^ not found in this scope
--Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
 
 error[E0268]: `break` outside of a loop or labeled block
   --> $DIR/track.rs:LL:CC
    |
 LL |     break rust
    |     ^^^^^^^^^^ cannot `break` outside of a loop or labeled block
--Ztrack-diagnostics: created at compiler/rustc_hir_typeck/src/loops.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_hir_typeck/src/loops.rs:LL:CC
 
 error: internal compiler error: It looks like you're trying to break rust; would you like some ICE?
   --> $DIR/track.rs:LL:CC
    |
 LL |     break rust
    |     ^^^^^^^^^^
--Ztrack-diagnostics: created at compiler/rustc_hir_typeck/src/lib.rs:LL:CC
    |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_hir_typeck/src/lib.rs:LL:CC
    = note: the compiler expectedly panicked. this is a feature.
    = note: we would appreciate a joke overview: https://github.com/rust-lang/rust/issues/43162#issuecomment-320764675
    = note: rustc $VERSION running on $TARGET

tests/ui/track-diagnostics/track2.stderr

@@ -6,8 +6,8 @@ LL |     let _moved @ _from = String::from("foo");
    |         |        |
    |         |        value moved here
    |         value used here after move
--Ztrack-diagnostics: created at compiler/rustc_borrowck/src/borrowck_errors.rs:LL:CC
    |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_borrowck/src/borrowck_errors.rs:LL:CC
 help: borrow this binding in the pattern to avoid moving the value
    |
 LL |     let ref _moved @ ref _from = String::from("foo");

tests/ui/track-diagnostics/track3.stderr

@@ -3,14 +3,16 @@ error[E0422]: cannot find struct, variant or union type `Blah` in this scope
    |
 LL |     let _unimported = Blah { field: u8 };
    |                       ^^^^ not found in this scope
--Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
 
 error[E0423]: expected value, found builtin type `u8`
   --> $DIR/track3.rs:LL:CC
    |
 LL |     let _unimported = Blah { field: u8 };
    |                                     ^^ not a value
--Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_resolve/src/late/diagnostics.rs:LL:CC
 
 error: aborting due to 2 previous errors
 

tests/ui/track-diagnostics/track4.stderr

@@ -3,8 +3,8 @@ error: missing `enum` for enum definition
    |
 LL | pub onion {
    | ^^^^^^^^^
--Ztrack-diagnostics: created at compiler/rustc_parse/src/parser/item.rs:LL:CC
    |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_parse/src/parser/item.rs:LL:CC
 help: add `enum` here to parse `onion` as an enum
    |
 LL | pub enum onion {

tests/ui/track-diagnostics/track5.stderr

@@ -3,7 +3,8 @@ error: unexpected closing delimiter: `}`
    |
 LL | }
    | ^ unexpected closing delimiter
--Ztrack-diagnostics: created at compiler/rustc_parse/src/lexer/tokentrees.rs:LL:CC
+   |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_parse/src/lexer/tokentrees.rs:LL:CC
 
 error: aborting due to 1 previous error
 

tests/ui/track-diagnostics/track6.stderr

@@ -3,8 +3,8 @@ error[E0658]: specialization is unstable
    |
 LL |     default fn bar() {}
    |     ^^^^^^^^^^^^^^^^^^^
--Ztrack-diagnostics: created at compiler/rustc_ast_passes/src/feature_gate.rs:LL:CC
    |
+   = note: -Ztrack-diagnostics: created at compiler/rustc_ast_passes/src/feature_gate.rs:LL:CC
    = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
    = help: add `#![feature(specialization)]` to the crate attributes to enable
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date