bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-diagnostics/src/handlers/unimplemented_trait.rs')
-rw-r--r--crates/ide-diagnostics/src/handlers/unimplemented_trait.rs53
1 files changed, 53 insertions, 0 deletions
diff --git a/crates/ide-diagnostics/src/handlers/unimplemented_trait.rs b/crates/ide-diagnostics/src/handlers/unimplemented_trait.rs
new file mode 100644
index 0000000000..4326aec458
--- /dev/null
+++ b/crates/ide-diagnostics/src/handlers/unimplemented_trait.rs
@@ -0,0 +1,53 @@
+use hir::HirDisplay;
+
+use crate::{Diagnostic, DiagnosticCode, DiagnosticsContext};
+
+// Diagnostic: type-must-be-known
+//
+// This diagnostic is triggered when rust-analyzer cannot infer some type.
+pub(crate) fn unimplemented_trait<'db>(
+ ctx: &DiagnosticsContext<'_, 'db>,
+ d: &hir::UnimplementedTrait<'db>,
+) -> Diagnostic {
+ let message = match &d.root_trait_predicate {
+ Some(root_predicate) if *root_predicate != d.trait_predicate => format!(
+ "the trait bound `{}` is not satisfied\n\
+ required by the bound `{}`\n",
+ d.trait_predicate.display(ctx.db(), ctx.display_target),
+ root_predicate.display(ctx.db(), ctx.display_target),
+ ),
+ _ => format!(
+ "the trait bound `{}` is not satisfied",
+ d.trait_predicate.display(ctx.db(), ctx.display_target),
+ ),
+ };
+ Diagnostic::new_with_syntax_node_ptr(
+ ctx,
+ DiagnosticCode::RustcHardError("E0277"),
+ message,
+ d.span.map(Into::into),
+ )
+}
+
+#[cfg(test)]
+mod tests {
+ use crate::tests::check_diagnostics;
+
+ #[test]
+ fn smoke_test() {
+ check_diagnostics(
+ r#"
+trait Trait {}
+impl<T: Trait, const N: usize> Trait for [T; N] {}
+fn foo(_v: impl Trait) {}
+fn bar() {
+ foo(1);
+ // ^^^ error: the trait bound `i32: Trait` is not satisfied
+ foo([1]);
+ // ^^^ error: the trait bound `i32: Trait` is not satisfied
+ // | required by the bound `[i32; 1]: Trait`
+}
+ "#,
+ );
+ }
+}