7 files changed, 39 insertions, 19 deletions

diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index ed07d6928..c0b0b7841 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -568,9 +568,13 @@ impl ExprCollector<'_> {
 
         let res = match res {
             Ok(res) => res,
-            Err(UnresolvedMacro) => {
+            Err(UnresolvedMacro { path }) => {
                 self.source_map.diagnostics.push(BodyDiagnostic::UnresolvedMacroCall(
-                    UnresolvedMacroCall { file: outer_file, node: syntax_ptr.cast().unwrap() },
+                    UnresolvedMacroCall {
+                        file: outer_file,
+                        node: syntax_ptr.cast().unwrap(),
+                        path,
+                    },
                 ));
                 collector(self, None);
                 return;
diff --git a/crates/hir_def/src/body/tests.rs b/crates/hir_def/src/body/tests.rs
index c1d3e998f..63f5fe88d 100644
--- a/crates/hir_def/src/body/tests.rs
+++ b/crates/hir_def/src/body/tests.rs
@@ -180,7 +180,7 @@ fn unresolved_macro_diag() {
         r#"
 fn f() {
     m!();
-  //^^^^ unresolved macro call
+  //^^^^ unresolved macro `m!`
 }
       "#,
     );
diff --git a/crates/hir_def/src/diagnostics.rs b/crates/hir_def/src/diagnostics.rs
index 97abf8653..a71ae2668 100644
--- a/crates/hir_def/src/diagnostics.rs
+++ b/crates/hir_def/src/diagnostics.rs
@@ -8,7 +8,7 @@ use hir_expand::diagnostics::{Diagnostic, DiagnosticCode, DiagnosticSink};
 use hir_expand::{HirFileId, InFile};
 use syntax::{ast, AstPtr, SyntaxNodePtr, TextRange};
 
-use crate::{db::DefDatabase, DefWithBodyId};
+use crate::{db::DefDatabase, path::ModPath, DefWithBodyId};
 
 pub fn validate_body(db: &dyn DefDatabase, owner: DefWithBodyId, sink: &mut DiagnosticSink<'_>) {
     let source_map = db.body_with_source_map(owner).1;
@@ -103,6 +103,7 @@ impl Diagnostic for UnresolvedImport {
 pub struct UnresolvedMacroCall {
     pub file: HirFileId,
     pub node: AstPtr<ast::MacroCall>,
+    pub path: ModPath,
 }
 
 impl Diagnostic for UnresolvedMacroCall {
@@ -110,7 +111,7 @@ impl Diagnostic for UnresolvedMacroCall {
         DiagnosticCode("unresolved-macro-call")
     }
     fn message(&self) -> String {
-        "unresolved macro call".to_string()
+        format!("unresolved macro `{}!`", self.path)
     }
     fn display_source(&self) -> InFile<SyntaxNodePtr> {
         InFile::new(self.file, self.node.clone().into())
diff --git a/crates/hir_def/src/lib.rs b/crates/hir_def/src/lib.rs
index ffee05500..000567d99 100644
--- a/crates/hir_def/src/lib.rs
+++ b/crates/hir_def/src/lib.rs
@@ -66,6 +66,7 @@ use hir_expand::{
 };
 use la_arena::Idx;
 use nameres::DefMap;
+use path::ModPath;
 use syntax::ast;
 
 use crate::builtin_type::BuiltinType;
@@ -675,7 +676,9 @@ impl<T: ast::AstNode> AstIdWithPath<T> {
     }
 }
 
-pub struct UnresolvedMacro;
+pub struct UnresolvedMacro {
+    pub path: ModPath,
+}
 
 fn macro_call_as_call_id(
     call: &AstIdWithPath<ast::MacroCall>,
@@ -684,7 +687,8 @@ fn macro_call_as_call_id(
     resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
     error_sink: &mut dyn FnMut(mbe::ExpandError),
 ) -> Result<Result<MacroCallId, ErrorEmitted>, UnresolvedMacro> {
-    let def: MacroDefId = resolver(call.path.clone()).ok_or(UnresolvedMacro)?;
+    let def: MacroDefId =
+        resolver(call.path.clone()).ok_or_else(|| UnresolvedMacro { path: call.path.clone() })?;
 
     let res = if let MacroDefKind::BuiltInEager(..) = def.kind {
         let macro_call = InFile::new(call.ast_id.file_id, call.ast_id.to_node(db.upcast()));
@@ -714,8 +718,13 @@ fn derive_macro_as_call_id(
     krate: CrateId,
     resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
 ) -> Result<MacroCallId, UnresolvedMacro> {
-    let def: MacroDefId = resolver(item_attr.path.clone()).ok_or(UnresolvedMacro)?;
-    let last_segment = item_attr.path.segments().last().ok_or(UnresolvedMacro)?;
+    let def: MacroDefId = resolver(item_attr.path.clone())
+        .ok_or_else(|| UnresolvedMacro { path: item_attr.path.clone() })?;
+    let last_segment = item_attr
+        .path
+        .segments()
+        .last()
+        .ok_or_else(|| UnresolvedMacro { path: item_attr.path.clone() })?;
     let res = def
         .as_lazy_macro(
             db.upcast(),
diff --git a/crates/hir_def/src/nameres.rs b/crates/hir_def/src/nameres.rs
index 9e181751c..542f190a1 100644
--- a/crates/hir_def/src/nameres.rs
+++ b/crates/hir_def/src/nameres.rs
@@ -481,7 +481,7 @@ mod diagnostics {
 
         UnresolvedProcMacro { ast: MacroCallKind },
 
-        UnresolvedMacroCall { ast: AstId<ast::MacroCall> },
+        UnresolvedMacroCall { ast: AstId<ast::MacroCall>, path: ModPath },
 
         MacroError { ast: MacroCallKind, message: String },
     }
@@ -546,8 +546,9 @@ mod diagnostics {
         pub(super) fn unresolved_macro_call(
             container: LocalModuleId,
             ast: AstId<ast::MacroCall>,
+            path: ModPath,
         ) -> Self {
-            Self { in_module: container, kind: DiagnosticKind::UnresolvedMacroCall { ast } }
+            Self { in_module: container, kind: DiagnosticKind::UnresolvedMacroCall { ast, path } }
         }
 
         pub(super) fn add_to(
@@ -662,9 +663,13 @@ mod diagnostics {
                     });
                 }
 
-                DiagnosticKind::UnresolvedMacroCall { ast } => {
+                DiagnosticKind::UnresolvedMacroCall { ast, path } => {
                     let node = ast.to_node(db.upcast());
-                    sink.push(UnresolvedMacroCall { file: ast.file_id, node: AstPtr::new(&node) });
+                    sink.push(UnresolvedMacroCall {
+                        file: ast.file_id,
+                        node: AstPtr::new(&node),
+                        path: path.clone(),
+                    });
                 }
 
                 DiagnosticKind::MacroError { ast, message } => {
diff --git a/crates/hir_def/src/nameres/collector.rs b/crates/hir_def/src/nameres/collector.rs
index fb4ddff5e..05ceb1efb 100644
--- a/crates/hir_def/src/nameres/collector.rs
+++ b/crates/hir_def/src/nameres/collector.rs
@@ -829,7 +829,7 @@ impl DefCollector<'_> {
                             res = ReachedFixedPoint::No;
                             return false;
                         }
-                        Err(UnresolvedMacro) | Ok(Err(_)) => {}
+                        Err(UnresolvedMacro { .. }) | Ok(Err(_)) => {}
                     }
                 }
                 MacroDirectiveKind::Derive { ast_id, derive_attr } => {
@@ -845,7 +845,7 @@ impl DefCollector<'_> {
                             res = ReachedFixedPoint::No;
                             return false;
                         }
-                        Err(UnresolvedMacro) => (),
+                        Err(UnresolvedMacro { .. }) => (),
                     }
                 }
             }
@@ -943,10 +943,11 @@ impl DefCollector<'_> {
                     &mut |_| (),
                 ) {
                     Ok(_) => (),
-                    Err(UnresolvedMacro) => {
+                    Err(UnresolvedMacro { path }) => {
                         self.def_map.diagnostics.push(DefDiagnostic::unresolved_macro_call(
                             directive.module_id,
                             ast_id.ast_id,
+                            path,
                         ));
                     }
                 },
@@ -1530,7 +1531,7 @@ impl ModCollector<'_, '_> {
                 ));
                 return;
             }
-            Err(UnresolvedMacro) => (),
+            Err(UnresolvedMacro { .. }) => (),
         }
 
         // Case 2: resolve in module scope, expand during name resolution.
diff --git a/crates/hir_def/src/nameres/tests/diagnostics.rs b/crates/hir_def/src/nameres/tests/diagnostics.rs
index 1ac88fc89..543975e07 100644
--- a/crates/hir_def/src/nameres/tests/diagnostics.rs
+++ b/crates/hir_def/src/nameres/tests/diagnostics.rs
@@ -170,7 +170,7 @@ fn unresolved_legacy_scope_macro() {
 
           m!();
           m2!();
-        //^^^^^^ unresolved macro call
+        //^^^^^^ unresolved macro `self::m2!`
         "#,
     );
 }
@@ -187,7 +187,7 @@ fn unresolved_module_scope_macro() {
 
           self::m!();
           self::m2!();
-        //^^^^^^^^^^^^ unresolved macro call
+        //^^^^^^^^^^^^ unresolved macro `self::m2!`
         "#,
     );
 }