bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide/src/inlay_hints/closure_ret.rs')
-rw-r--r--crates/ide/src/inlay_hints/closure_ret.rs51
1 files changed, 51 insertions, 0 deletions
diff --git a/crates/ide/src/inlay_hints/closure_ret.rs b/crates/ide/src/inlay_hints/closure_ret.rs
new file mode 100644
index 0000000000..de04f3ac75
--- /dev/null
+++ b/crates/ide/src/inlay_hints/closure_ret.rs
@@ -0,0 +1,51 @@
+//! Implementation of "closure return type" inlay hints.
+use hir::{HirDisplay, Semantics};
+use ide_db::{base_db::FileId, famous_defs::FamousDefs, RootDatabase};
+use syntax::ast::{self, AstNode};
+
+use crate::{
+ inlay_hints::{closure_has_block_body, hint_iterator},
+ ClosureReturnTypeHints, InlayHint, InlayHintsConfig, InlayKind, InlayTooltip,
+};
+
+pub(super) fn hints(
+ acc: &mut Vec<InlayHint>,
+ sema: &Semantics<'_, RootDatabase>,
+ famous_defs: &FamousDefs<'_, '_>,
+ config: &InlayHintsConfig,
+ file_id: FileId,
+ closure: ast::ClosureExpr,
+) -> Option<()> {
+ if config.closure_return_type_hints == ClosureReturnTypeHints::Never {
+ return None;
+ }
+
+ if closure.ret_type().is_some() {
+ return None;
+ }
+
+ if !closure_has_block_body(&closure)
+ && config.closure_return_type_hints == ClosureReturnTypeHints::WithBlock
+ {
+ return None;
+ }
+
+ let param_list = closure.param_list()?;
+
+ let closure = sema.descend_node_into_attributes(closure.clone()).pop()?;
+ let ty = sema.type_of_expr(&ast::Expr::ClosureExpr(closure))?.adjusted();
+ let callable = ty.as_callable(sema.db)?;
+ let ty = callable.return_type();
+ if ty.is_unit() {
+ return None;
+ }
+ acc.push(InlayHint {
+ range: param_list.syntax().text_range(),
+ kind: InlayKind::ClosureReturnTypeHint,
+ label: hint_iterator(sema, &famous_defs, config, &ty)
+ .unwrap_or_else(|| ty.display_truncated(sema.db, config.max_length).to_string())
+ .into(),
+ tooltip: Some(InlayTooltip::HoverRanged(file_id, param_list.syntax().text_range())),
+ });
+ Some(())
+}