fix: Don't add an end column separator after a file with no source

Author: Muscraft

compiler/rustc_errors/src/emitter.rs

@@ -1462,7 +1462,7 @@ impl HumanEmitter {
         max_line_num_len: usize,
         is_secondary: bool,
         is_cont: bool,
-    ) -> io::Result<()> {
+    ) -> io::Result<Option<bool>> {
         let mut buffer = StyledBuffer::new();
 
         if !msp.has_primary_spans() && !msp.has_span_labels() && is_secondary && !self.short_message
@@ -1580,7 +1580,8 @@ impl HumanEmitter {
         let primary_span = msp.primary_span().unwrap_or_default();
         let (Some(sm), false) = (self.sm.as_ref(), primary_span.is_dummy()) else {
             // If we don't have span information, emit and exit
-            return emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message);
+            return emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)
+                .map(|_| None);
         };
         let primary_lo = sm.lookup_char_pos(primary_span.lo());
         if let Ok(pos) =
@@ -1589,6 +1590,7 @@ impl HumanEmitter {
             annotated_files.swap(0, pos);
         }
 
+        let mut already_closed = None;
         let annotated_files_len = annotated_files.len();
         // Print out the annotate source lines that correspond with the error
         for (file_idx, annotated_file) in annotated_files.into_iter().enumerate() {
@@ -1639,6 +1641,12 @@ impl HumanEmitter {
                             }
                             line_idx += 1;
                         }
+                        if is_cont
+                            && file_idx == annotated_files_len - 1
+                            && annotation_id == annotated_file.lines.len() - 1
+                        {
+                            already_closed = Some(!labels.is_empty());
+                        }
                         for (label, is_primary) in labels.into_iter() {
                             let style = if is_primary {
                                 Style::LabelPrimary
@@ -1976,7 +1984,7 @@ impl HumanEmitter {
         // final step: take our styled buffer, render it, then output it
         emit_to_destination(&buffer.render(), level, &mut self.dst, self.short_message)?;
 
-        Ok(())
+        Ok(already_closed)
     }
 
     fn column_width(&self, code_offset: usize) -> usize {
@@ -2491,7 +2499,7 @@ impl HumanEmitter {
             !children.is_empty()
                 || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden),
         ) {
-            Ok(()) => {
+            Ok(already_closed) => {
                 if !children.is_empty()
                     || suggestions.iter().any(|s| s.style != SuggestionStyle::CompletelyHidden)
                 {
@@ -2502,7 +2510,7 @@ impl HumanEmitter {
                         {
                             // 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);
-                        } else {
+                        } else if !already_closed.is_some_and(|ac| ac) {
                             // 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);
                         }

tests/ui/c-variadic/issue-86053-1.stderr

@@ -60,7 +60,6 @@ LL |     self , ... ,   self ,   self , ... ) where F : FnOnce ( & 'a & 'b usize
   --> $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
    = note: similarly named trait `Fn` defined here
-   |
 help: a trait with a similar name exists
    |
 LL |     self , ... ,   self ,   self , ... ) where Fn : FnOnce ( & 'a & 'b usize ) {

tests/ui/closures/issue-78720.stderr

@@ -12,7 +12,6 @@ LL |     _func: F,
   --> $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
    = note: similarly named trait `Fn` defined here
-   |
 help: a trait with a similar name exists
    |
 LL |     _func: Fn,

tests/ui/const-generics/generic_const_exprs/expected-type-of-closure-body-to-be-a-closure-or-coroutine-ice-113776.stderr

@@ -6,7 +6,6 @@ LL |          let f: F = async { 1 };
   --> $SRC_DIR/core/src/ops/function.rs:LL:COL
    |
    = note: similarly named trait `Fn` defined here
-   |
 help: a trait with a similar name exists
    |
 LL |          let f: Fn = async { 1 };

tests/ui/imports/suggest-remove-issue-121315.stderr

@@ -6,7 +6,6 @@ LL |     use std::convert::TryFrom;
   --> $SRC_DIR/std/src/prelude/mod.rs:LL:COL
    |
    = note: the item `TryFrom` is already defined here
-   |
 note: the lint level is defined here
   --> $DIR/suggest-remove-issue-121315.rs:2:25
    |

tests/ui/issues/issue-17546.stderr

@@ -6,7 +6,6 @@ LL |     fn new() -> NoResult<MyEnum, String> {
   --> $SRC_DIR/core/src/result.rs:LL:COL
    |
    = note: similarly named enum `Result` defined here
-   |
 help: try using the variant's enum
    |
 LL -     fn new() -> NoResult<MyEnum, String> {
@@ -60,7 +59,6 @@ LL | fn newer() -> NoResult<foo::MyEnum, String> {
   --> $SRC_DIR/core/src/result.rs:LL:COL
    |
    = note: similarly named enum `Result` defined here
-   |
 help: try using the variant's enum
    |
 LL - fn newer() -> NoResult<foo::MyEnum, String> {

tests/ui/lint/use-redundant/use-redundant-issue-71450.stderr

@@ -6,7 +6,6 @@ LL |         use std::string::String;
   --> $SRC_DIR/std/src/prelude/mod.rs:LL:COL
    |
    = note: the item `String` is already defined here
-   |
 note: the lint level is defined here
   --> $DIR/use-redundant-issue-71450.rs:3:9
    |

tests/ui/lint/use-redundant/use-redundant-prelude-rust-2015.stderr

@@ -6,7 +6,6 @@ LL | use std::option::Option::Some;
   --> $SRC_DIR/std/src/prelude/mod.rs:LL:COL
    |
    = note: the item `Some` is already defined here
-   |
 note: the lint level is defined here
   --> $DIR/use-redundant-prelude-rust-2015.rs:3:9
    |

tests/ui/lint/use-redundant/use-redundant-prelude-rust-2021.stderr

@@ -6,7 +6,6 @@ LL | use std::convert::TryFrom;
   --> $SRC_DIR/std/src/prelude/mod.rs:LL:COL
    |
    = note: the item `TryFrom` is already defined here
-   |
 note: the lint level is defined here
   --> $DIR/use-redundant-prelude-rust-2021.rs:3:9
    |

tests/ui/macros/missing-writer-issue-139830.stderr

@@ -6,7 +6,6 @@ LL |     let _ = write!(buf, "foo");
   --> $SRC_DIR/core/src/fmt/mod.rs:LL:COL
    |
    = note: the method is available for `String` here
-   |
 note: must implement `io::Write`, `fmt::Write`, or have a `write_fmt` method
   --> $DIR/missing-writer-issue-139830.rs:7:20
    |