From 7a4fd3e1e9ecfa5c6b5c00f14b0c192a2785152a Mon Sep 17 00:00:00 2001
From: Scott Schafer <schaferjscott@gmail.com>
Date: Thu, 3 Jul 2025 14:48:28 -0600
Subject: [PATCH 1/2] test: Add test for Message text ending with \n

---
 tests/rustc_tests.rs | 74 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

diff --git a/tests/rustc_tests.rs b/tests/rustc_tests.rs
index b32dd8f..52e8bbe 100644
--- a/tests/rustc_tests.rs
+++ b/tests/rustc_tests.rs
@@ -3370,3 +3370,77 @@ note: the traits `Iterator` and `ToTokens` must be implemented
     let renderer = renderer.theme(OutputTheme::Unicode);
     assert_data_eq!(renderer.render(input), expected_unicode);
 }
+
+#[test]
+fn not_found_self_type_differs_shadowing_trait_item() {
+    // tests/ui/associated-inherent-types/not-found-self-type-differs-shadowing-trait-item.rs
+
+    let source = r#"#![feature(inherent_associated_types)]
+#![allow(incomplete_features)]
+
+// Check that it's okay to report “[inherent] associated type […] not found” for inherent associated
+// type candidates that are not applicable (due to unsuitable Self type) even if there exists a
+// “shadowed” associated type from a trait with the same name since its use would be ambiguous
+// anyway if the IAT didn't exist.
+// FIXME(inherent_associated_types): Figure out which error would be more helpful here.
+
+//@ revisions: shadowed uncovered
+
+struct S<T>(T);
+
+trait Tr {
+    type Pr;
+}
+
+impl<T> Tr for S<T> {
+    type Pr = ();
+}
+
+#[cfg(shadowed)]
+impl S<()> {
+    type Pr = i32;
+}
+
+fn main() {
+    let _: S::<bool>::Pr = ();
+    //[shadowed]~^ ERROR associated type `Pr` not found
+    //[uncovered]~^^ ERROR associated type `Pr` not found
+}
+"#;
+
+    let input = &[Group::with_title(
+        Level::ERROR
+            .title("associated type `Pr` not found for `S<bool>` in the current scope")
+            .id("E0220"),
+    )
+    .element(
+        Snippet::source(source)
+            .path("$DIR/not-found-self-type-differs-shadowing-trait-item.rs")
+            .annotation(
+                AnnotationKind::Primary
+                    .span(705..707)
+                    .label("associated item not found in `S<bool>`"),
+            )
+            .annotation(
+                AnnotationKind::Context
+                    .span(532..543)
+                    .label("associated type `Pr` not found for this struct"),
+            ),
+    )
+    .element(Level::NOTE.title("the associated type was found for\n"))];
+
+    let expected = str![[r#"
+error[E0220]: associated type `Pr` not found for `S<bool>` in the current scope
+  --> $DIR/not-found-self-type-differs-shadowing-trait-item.rs:28:23
+   |
+LL | struct S<T>(T);
+   | ----------- associated type `Pr` not found for this struct
+...
+LL |     let _: S::<bool>::Pr = ();
+   |                       ^^ associated item not found in `S<bool>`
+   |
+   = note: the associated type was found for
+"#]];
+    let renderer = Renderer::plain().anonymized_line_numbers(true);
+    assert_data_eq!(renderer.render(input), expected);
+}

From 82abe2699d655cb946bbf7684b67a5e7291051f2 Mon Sep 17 00:00:00 2001
From: Scott Schafer <schaferjscott@gmail.com>
Date: Thu, 3 Jul 2025 14:56:12 -0600
Subject: [PATCH 2/2] fix: Render newline if a Message ends with one

---
 src/renderer/mod.rs  | 2 +-
 tests/rustc_tests.rs | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs
index 80a8811..8d3c6a2 100644
--- a/src/renderer/mod.rs
+++ b/src/renderer/mod.rs
@@ -636,7 +636,7 @@ impl Renderer {
         } else {
             (normalize_whitespace(title.text()), title_element_style)
         };
-        for (i, text) in title_str.lines().enumerate() {
+        for (i, text) in title_str.split('\n').enumerate() {
             if i != 0 {
                 buffer.append(buffer_msg_line_offset + i, &padding, ElementStyle::NoStyle);
                 if title_style == TitleStyle::Secondary
diff --git a/tests/rustc_tests.rs b/tests/rustc_tests.rs
index 52e8bbe..dd5dbe8 100644
--- a/tests/rustc_tests.rs
+++ b/tests/rustc_tests.rs
@@ -3440,6 +3440,7 @@ LL |     let _: S::<bool>::Pr = ();
    |                       ^^ associated item not found in `S<bool>`
    |
    = note: the associated type was found for
+           
 "#]];
     let renderer = Renderer::plain().anonymized_line_numbers(true);
     assert_data_eq!(renderer.render(input), expected);