test: Add a test for styled Title's

Author: Muscraft

tests/color/main.rs

@@ -16,3 +16,4 @@ mod simple;
 mod strip_line;
 mod strip_line_char;
 mod strip_line_non_ws;
+mod styled_title;

tests/color/styled_title.rs

@@ -0,0 +1,43 @@
+use annotate_snippets::{AnnotationKind, Group, Level, Renderer, Snippet};
+use anstyle::{AnsiColor, Effects, Style};
+
+use snapbox::{assert_data_eq, file};
+
+const MAGENTA: Style = AnsiColor::Magenta.on_default().effects(Effects::BOLD);
+const BOLD: Style = Style::new().effects(Effects::BOLD);
+#[test]
+fn case() {
+    let source = r#"use b::CustomErrorHandler;
+use c::cnb_runtime;
+
+
+    cnb_runtime(CustomErrorHandler {});
+"#;
+
+    let title_1 = "the trait bound `CustomErrorHandler: ErrorHandler` is not satisfied";
+    let title_2 = format!("{BOLD}there are {BOLD:#}{MAGENTA}multiple different versions{MAGENTA:#}{BOLD} of crate `{BOLD:#}{MAGENTA}c{MAGENTA:#}{BOLD}` in the dependency graph{BOLD:#}");
+
+    let label_1 = "the trait `ErrorHandler` is not implemented for `CustomErrorHandler`";
+    let label_2 = "required by a bound introduced by this call";
+    let label_3 = "one version of crate `c` is used here, as a dependency of crate `b`";
+    let label_4 =
+        "one version of crate `c` is used here, as a direct dependency of the current crate";
+
+    let input = &[
+        Group::with_title(Level::ERROR.primary_title(title_1).id("E0277")).element(
+            Snippet::source(source)
+                .path("src/main.rs")
+                .annotation(AnnotationKind::Primary.span(65..86).label(label_1))
+                .annotation(AnnotationKind::Context.span(53..64).label(label_2)),
+        ),
+        Group::with_title(Level::HELP.primary_title(title_2)).element(
+            Snippet::source(source)
+                .path("src/main.rs")
+                .annotation(AnnotationKind::Primary.span(4..5).label(label_3))
+                .annotation(AnnotationKind::Primary.span(31..32).label(label_4)),
+        ),
+    ];
+    let expected = file!["styled_title.term.svg"];
+    let renderer = Renderer::styled();
+    assert_data_eq!(renderer.render(input), expected);
+}