Allow flyimporting excluded trait items if there is an exact match in the name

I.e. with `fn foo()`, don't complete at `x.fo|`, but complete (with imports) for `x.foo|`, since this is less likely to have false positives.

I opted to only do that for flyimport, even though for basic imports there can also be snippet completion (completing the params list for a method), since this is less universally applicable and seems not so useful.

Author: ChayimFriedman2

src/tools/rust-analyzer/crates/ide-completion/src/completions/flyimport.rs

@@ -258,6 +258,8 @@ fn import_on_the_fly(
 
     let import_cfg = ctx.config.import_path_config();
 
+    let completed_name = ctx.token.to_string();
+
     import_assets
         .search_for_imports(&ctx.sema, import_cfg, ctx.config.insert_use.prefix_kind)
         .filter(ns_filter)
@@ -271,7 +273,13 @@ fn import_on_the_fly(
             if let ModuleDef::Trait(trait_) = import.item_to_import.into_module_def() {
                 let excluded = ctx.exclude_flyimport_traits.contains(&trait_);
                 let trait_itself_imported = import.item_to_import == import.original_item;
-                !excluded || trait_itself_imported
+                if !excluded || trait_itself_imported {
+                    return true;
+                }
+
+                let item = import.original_item.into_module_def();
+                // Filter that item out, unless its name matches the name the user wrote exactly - in which case preserve it.
+                item.name(ctx.db).is_some_and(|name| name.eq_ident(&completed_name))
             } else {
                 true
             }
@@ -355,6 +363,8 @@ fn import_on_the_fly_method(
 
     let cfg = ctx.config.import_path_config();
 
+    let completed_name = ctx.token.to_string();
+
     import_assets
         .search_for_imports(&ctx.sema, cfg, ctx.config.insert_use.prefix_kind)
         .filter(|import| {
@@ -363,7 +373,13 @@ fn import_on_the_fly_method(
         })
         .filter(|import| {
             if let ModuleDef::Trait(trait_) = import.item_to_import.into_module_def() {
-                !ctx.exclude_flyimport_traits.contains(&trait_)
+                if !ctx.exclude_flyimport_traits.contains(&trait_) {
+                    return true;
+                }
+
+                let item = import.original_item.into_module_def();
+                // Filter that method out, unless its name matches the name the user wrote exactly - in which case preserve it.
+                item.name(ctx.db).is_some_and(|name| name.eq_ident(&completed_name))
             } else {
                 true
             }

src/tools/rust-analyzer/crates/ide-completion/src/tests/flyimport.rs

@@ -3,10 +3,14 @@ use expect_test::{expect, Expect};
 use crate::{
     context::{CompletionAnalysis, NameContext, NameKind, NameRefKind},
     tests::{check_edit, check_edit_with_config, TEST_CONFIG},
+    CompletionConfig,
 };
 
 fn check(ra_fixture: &str, expect: Expect) {
-    let config = TEST_CONFIG;
+    check_with_config(TEST_CONFIG, ra_fixture, expect);
+}
+
+fn check_with_config(config: CompletionConfig<'_>, ra_fixture: &str, expect: Expect) {
     let (db, position) = crate::tests::position(ra_fixture);
     let (ctx, analysis) = crate::context::CompletionContext::new(&db, position, &config).unwrap();
 
@@ -1762,3 +1766,31 @@ fn function() {
         expect![""],
     );
 }
+
+#[test]
+fn excluded_trait_item_included_when_exact_match() {
+    check_with_config(
+        CompletionConfig {
+            exclude_traits: &["test::module2::ExcludedTrait".to_owned()],
+            ..TEST_CONFIG
+        },
+        r#"
+mod module2 {
+    pub trait ExcludedTrait {
+        fn foo(&self) {}
+        fn bar(&self) {}
+        fn baz(&self) {}
+    }
+
+    impl<T> ExcludedTrait for T {}
+}
+
+fn foo() {
+    true.foo$0
+}
+        "#,
+        expect![[r#"
+            me foo() (use module2::ExcludedTrait) fn(&self)
+        "#]],
+    );
+}