Fix edge case for ImportGranularity guessing

2 files changed, 26 insertions, 7 deletions

diff --git a/crates/ide_db/src/helpers/insert_use.rs b/crates/ide_db/src/helpers/insert_use.rs
index aa61c5bcb..10bbafe77 100644
--- a/crates/ide_db/src/helpers/insert_use.rs
+++ b/crates/ide_db/src/helpers/insert_use.rs
@@ -120,15 +120,19 @@ impl ImportScope {
             if eq_visibility(prev_vis, curr_vis.clone()) && eq_attrs(prev_attrs, curr_attrs.clone())
             {
                 if let Some((prev_path, curr_path)) = prev.path().zip(curr.path()) {
-                    if let Some(_) = common_prefix(&prev_path, &curr_path) {
+                    if let Some((prev_prefix, _)) = common_prefix(&prev_path, &curr_path) {
                         if prev.use_tree_list().is_none() && curr.use_tree_list().is_none() {
-                            // Same prefix but no use tree lists so this has to be of item style.
-                            break ImportGranularityGuess::Item; // this overwrites CrateOrModule, technically the file doesn't adhere to anything here.
-                        } else {
-                            // Same prefix with item tree lists, has to be module style as it
-                            // can't be crate style since the trees wouldn't share a prefix then.
-                            break ImportGranularityGuess::Module;
+                            let prefix_c = prev_prefix.qualifiers().count();
+                            let curr_c = curr_path.qualifiers().count() - prefix_c;
+                            let prev_c = prev_path.qualifiers().count() - prefix_c;
+                            if curr_c <= 1 || prev_c <= 1 {
+                                // Same prefix but no use tree lists so this has to be of item style.
+                                break ImportGranularityGuess::Item; // this overwrites CrateOrModule, technically the file doesn't adhere to anything here.
+                            }
                         }
+                        // Same prefix with item tree lists, has to be module style as it
+                        // can't be crate style since the trees wouldn't share a prefix then.
+                        break ImportGranularityGuess::Module;
                     }
                 }
             }
diff --git a/crates/ide_db/src/helpers/insert_use/tests.rs b/crates/ide_db/src/helpers/insert_use/tests.rs
index 78a2a87b3..70b11bf81 100644
--- a/crates/ide_db/src/helpers/insert_use/tests.rs
+++ b/crates/ide_db/src/helpers/insert_use/tests.rs
@@ -663,6 +663,13 @@ use foo::bar::qux;
 ",
         ImportGranularityGuess::Item,
     );
+    check_guess(
+        r"
+use foo::bar::Bar;
+use foo::baz;
+",
+        ImportGranularityGuess::Item,
+    );
 }
 
 #[test]
@@ -682,6 +689,14 @@ use foo::{baz::{qux, quux}, bar};
 ",
         ImportGranularityGuess::Module,
     );
+    check_guess(
+        r"
+use foo::bar::Bar;
+use foo::baz::Baz;
+use foo::{Foo, Qux};
+",
+        ImportGranularityGuess::Module,
+    );
 }
 
 #[test]