refactor: Always add a col seperator before -Ztrack-diagnostics

Author: Muscraft

compiler/rustc_errors/src/emitter.rs

@@ -2478,11 +2478,11 @@ impl HumanEmitter {
                 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}");
-                        buffer.append(0, &track, Style::NoStyle);
+                        buffer.append(1, &track, Style::NoStyle);
                     }
-                }
-                if !children.is_empty()
+                } else if !children.is_empty()
                     || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden)
                 {
                     let line_offest = buffer.num_lines();

tests/rustdoc-ui/track-diagnostics.stderr

@@ -3,6 +3,7 @@ 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
 
 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
 
 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
 
 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
    |
+-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
    |
+-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

@@ -3,13 +3,15 @@ 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
 
 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
 
 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
    |
+-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

@@ -3,6 +3,7 @@ error: unexpected closing delimiter: `}`
    |
 LL | }
    | ^ unexpected closing delimiter
+   |
 -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
    |
+-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