test: Add tests for custom Levels

Author: Muscraft

examples/custom_error.rs

@@ -0,0 +1,35 @@
+use annotate_snippets::renderer::OutputTheme;
+use annotate_snippets::{AnnotationKind, Group, Level, Renderer, Snippet};
+
+fn main() {
+    let source = r#"//@ compile-flags: -Ztreat-err-as-bug
+//@ failure-status: 101
+//@ error-pattern: aborting due to `-Z treat-err-as-bug=1`
+//@ error-pattern: [eval_static_initializer] evaluating initializer of static `C`
+//@ normalize-stderr: "note: .*\n\n" -> ""
+//@ normalize-stderr: "thread 'rustc' panicked.*:\n.*\n" -> ""
+//@ rustc-env:RUST_BACKTRACE=0
+
+#![crate_type = "rlib"]
+
+pub static C: u32 = 0 - 1;
+//~^ ERROR could not evaluate static initializer
+"#;
+    let message = Level::None
+        .message("error: internal compiler error[E0080]: could not evaluate static initializer")
+        .group(
+            Group::new().element(
+                Snippet::source(source)
+                    .origin("$DIR/err.rs")
+                    .fold(true)
+                    .annotation(
+                        AnnotationKind::Primary
+                            .span(386..391)
+                            .label("attempt to compute `0_u32 - 1_u32`, which would overflow"),
+                    ),
+            ),
+        );
+
+    let renderer = Renderer::styled().theme(OutputTheme::Unicode);
+    anstream::println!("{}", renderer.render(message));
+}

examples/custom_error.svg

@@ -0,0 +1,69 @@
+use annotate_snippets::renderer::OutputTheme;
+use annotate_snippets::{AnnotationKind, Group, Level, Patch, Renderer, Snippet};
+
+fn main() {
+    let source = r#"// Regression test for issue #114529
+// Tests that we do not ICE during const eval for a
+// break-with-value in contexts where it is illegal
+
+#[allow(while_true)]
+fn main() {
+    [(); {
+        while true {
+            break 9; //~ ERROR `break` with value from a `while` loop
+        };
+        51
+    }];
+
+    [(); {
+        while let Some(v) = Some(9) {
+            break v; //~ ERROR `break` with value from a `while` loop
+        };
+        51
+    }];
+
+    while true {
+        break (|| { //~ ERROR `break` with value from a `while` loop
+            let local = 9;
+        });
+    }
+}
+"#;
+    let message = Level::Error
+        .message("`break` with value from a `while` loop")
+        .id("E0571")
+        .group(
+            Group::new().element(
+                Snippet::source(source)
+                    .line_start(1)
+                    .origin("$DIR/issue-114529-illegal-break-with-value.rs")
+                    .fold(true)
+                    .annotation(
+                        AnnotationKind::Primary
+                            .span(483..581)
+                            .label("can only break with a value inside `loop` or breakable block"),
+                    )
+                    .annotation(
+                        AnnotationKind::Context
+                            .span(462..472)
+                            .label("you can't `break` with a value in a `while` loop"),
+                    ),
+            ),
+        )
+        .group(
+            Group::new()
+                .element(Level::None.title(
+                    "suggestion: use `break` on its own without a value inside this `while` loop",
+                ))
+                .element(
+                    Snippet::source(source)
+                        .line_start(1)
+                        .origin("$DIR/issue-114529-illegal-break-with-value.rs")
+                        .fold(true)
+                        .patch(Patch::new(483..581, "break")),
+                ),
+        );
+
+    let renderer = Renderer::styled().theme(OutputTheme::Unicode);
+    anstream::println!("{}", renderer.render(message));
+}

examples/custom_level.rs

@@ -1,3 +1,17 @@
+#[test]
+fn custom_error() {
+    let target = "custom_error";
+    let expected = snapbox::file!["../examples/custom_error.svg": TermSvg];
+    assert_example(target, expected);
+}
+
+#[test]
+fn custom_level() {
+    let target = "custom_level";
+    let expected = snapbox::file!["../examples/custom_level.svg": TermSvg];
+    assert_example(target, expected);
+}
+
 #[test]
 fn expected_type() {
     let target = "expected_type";