fix: If fold is false max_line_num is last source line

src/renderer/mod.rs

@@ -2919,26 +2919,34 @@ fn max_line_number(groups: &[Group<'_>]) -> usize {
                     | Element::Origin(_)
                     | Element::Padding(_) => 0,
                     Element::Cause(cause) => {
-                        let end = cause
-                            .markers
-                            .iter()
-                            .map(|a| a.span.end)
-                            .max()
-                            .unwrap_or(cause.source.len())
-                            .min(cause.source.len());
-
-                        cause.line_start + newline_count(&cause.source[..end])
+                        if cause.fold {
+                            let end = cause
+                                .markers
+                                .iter()
+                                .map(|a| a.span.end)
+                                .max()
+                                .unwrap_or(cause.source.len())
+                                .min(cause.source.len());
+
+                            cause.line_start + newline_count(&cause.source[..end])
+                        } else {
+                            cause.line_start + newline_count(&cause.source)
+                        }
                     }
                     Element::Suggestion(suggestion) => {
-                        let end = suggestion
-                            .markers
-                            .iter()
-                            .map(|a| a.span.end)
-                            .max()
-                            .unwrap_or(suggestion.source.len())
-                            .min(suggestion.source.len());
-
-                        suggestion.line_start + newline_count(&suggestion.source[..end])
+                        if suggestion.fold {
+                            let end = suggestion
+                                .markers
+                                .iter()
+                                .map(|a| a.span.end)
+                                .max()
+                                .unwrap_or(suggestion.source.len())
+                                .min(suggestion.source.len());
+
+                            suggestion.line_start + newline_count(&suggestion.source[..end])
+                        } else {
+                            suggestion.line_start + newline_count(&suggestion.source)
+                        }
                     }
                 })
                 .max()

tests/formatter.rs

@@ -2574,3 +2574,41 @@ LL +         break;
     let renderer_unicode = renderer_ascii.theme(OutputTheme::Unicode);
     assert_data_eq!(renderer_unicode.render(input), expected_unicode);
 }
+
+#[test]
+fn max_line_num_no_fold() {
+    let source = r#"cargo
+fuzzy
+pizza
+jumps
+crazy
+quack
+zappy
+"#;
+
+    let input_new = &[Group::with_title(
+        Level::ERROR
+            .title("the size for values of type `T` cannot be known at compilation time")
+            .id("E0277"),
+    )
+    .element(
+        Snippet::source(source)
+            .line_start(8)
+            .fold(false)
+            .annotation(AnnotationKind::Primary.span(6..11)),
+    )];
+    let expected = str![[r#"
+error[E0277]: the size for values of type `T` cannot be known at compilation time
+   |
+ 8 | cargo
+ 9 | fuzzy
+   | ^^^^^
+10 | pizza
+11 | jumps
+12 | crazy
+13 | quack
+14 | zappy
+"#]];
+    let renderer = Renderer::plain();
+    assert_data_eq!(renderer.render(input_new), expected);
+}