Auto merge of rust-lang#17523 - wada314:master, r=Veykril

Add an option to use "::" for the external crate prefix.

Fixes rust-lang#11823 .
Hi I'm very new to rust-analyzer and not sure how the review process are. Can somebody take a look at this PR? thanks!

Author: bors

src/tools/rust-analyzer/crates/hir-def/src/find_path.rs

@@ -183,6 +183,8 @@ fn find_path_for_module(
             let kind = if name_already_occupied_in_type_ns {
                 cov_mark::hit!(ambiguous_crate_start);
                 PathKind::Abs
+            } else if ctx.cfg.prefer_absolute {
+                PathKind::Abs
             } else {
                 PathKind::Plain
             };
@@ -564,7 +566,13 @@ mod tests {
     /// item the `path` refers to returns that same path when called from the
     /// module the cursor is in.
     #[track_caller]
-    fn check_found_path_(ra_fixture: &str, path: &str, prefer_prelude: bool, expect: Expect) {
+    fn check_found_path_(
+        ra_fixture: &str,
+        path: &str,
+        prefer_prelude: bool,
+        prefer_absolute: bool,
+        expect: Expect,
+    ) {
         let (db, pos) = TestDB::with_position(ra_fixture);
         let module = db.module_at_position(pos);
         let parsed_path_file =
@@ -604,7 +612,7 @@ mod tests {
                 module,
                 prefix,
                 ignore_local_imports,
-                ImportPathConfig { prefer_no_std: false, prefer_prelude },
+                ImportPathConfig { prefer_no_std: false, prefer_prelude, prefer_absolute },
             );
             format_to!(
                 res,
@@ -619,11 +627,15 @@ mod tests {
     }
 
     fn check_found_path(ra_fixture: &str, path: &str, expect: Expect) {
-        check_found_path_(ra_fixture, path, false, expect);
+        check_found_path_(ra_fixture, path, false, false, expect);
     }
 
     fn check_found_path_prelude(ra_fixture: &str, path: &str, expect: Expect) {
-        check_found_path_(ra_fixture, path, true, expect);
+        check_found_path_(ra_fixture, path, true, false, expect);
+    }
+
+    fn check_found_path_absolute(ra_fixture: &str, path: &str, expect: Expect) {
+        check_found_path_(ra_fixture, path, false, true, expect);
     }
 
     #[test]
@@ -870,6 +882,39 @@ pub mod ast {
         );
     }
 
+    #[test]
+    fn partially_imported_with_prefer_absolute() {
+        cov_mark::check!(partially_imported);
+        // Similar to partially_imported test case above, but with prefer_absolute enabled.
+        // Even if the actual imported item is in external crate, if the path to that item
+        // is starting from the imported name, then the path should not start from "::".
+        // i.e. The first line in the expected output should not start from "::".
+        check_found_path_absolute(
+            r#"
+//- /main.rs crate:main deps:syntax
+
+use syntax::ast;
+$0
+
+//- /lib.rs crate:syntax
+pub mod ast {
+    pub enum ModuleItem {
+        A, B, C,
+    }
+}
+        "#,
+            "syntax::ast::ModuleItem",
+            expect![[r#"
+                Plain  (imports ✔): ast::ModuleItem
+                Plain  (imports ✖): ::syntax::ast::ModuleItem
+                ByCrate(imports ✔): crate::ast::ModuleItem
+                ByCrate(imports ✖): ::syntax::ast::ModuleItem
+                BySelf (imports ✔): self::ast::ModuleItem
+                BySelf (imports ✖): ::syntax::ast::ModuleItem
+            "#]],
+        );
+    }
+
     #[test]
     fn same_crate_reexport() {
         check_found_path(
@@ -1769,6 +1814,43 @@ pub mod foo {
         );
     }
 
+    #[test]
+    fn respects_absolute_setting() {
+        let ra_fixture = r#"
+//- /main.rs crate:main deps:krate
+$0
+//- /krate.rs crate:krate
+pub mod foo {
+    pub struct Foo;
+}
+"#;
+        check_found_path(
+            ra_fixture,
+            "krate::foo::Foo",
+            expect![[r#"
+            Plain  (imports ✔): krate::foo::Foo
+            Plain  (imports ✖): krate::foo::Foo
+            ByCrate(imports ✔): krate::foo::Foo
+            ByCrate(imports ✖): krate::foo::Foo
+            BySelf (imports ✔): krate::foo::Foo
+            BySelf (imports ✖): krate::foo::Foo
+        "#]],
+        );
+
+        check_found_path_absolute(
+            ra_fixture,
+            "krate::foo::Foo",
+            expect![[r#"
+            Plain  (imports ✔): ::krate::foo::Foo
+            Plain  (imports ✖): ::krate::foo::Foo
+            ByCrate(imports ✔): ::krate::foo::Foo
+            ByCrate(imports ✖): ::krate::foo::Foo
+            BySelf (imports ✔): ::krate::foo::Foo
+            BySelf (imports ✖): ::krate::foo::Foo
+        "#]],
+        );
+    }
+
     #[test]
     fn respect_segment_length() {
         check_found_path(

src/tools/rust-analyzer/crates/hir-def/src/lib.rs

@@ -116,6 +116,8 @@ pub struct ImportPathConfig {
     pub prefer_no_std: bool,
     /// If true, prefer import paths containing a prelude module.
     pub prefer_prelude: bool,
+    /// If true, prefer abs path (starting with `::`) where it is available.
+    pub prefer_absolute: bool,
 }
 
 #[derive(Debug)]

src/tools/rust-analyzer/crates/hir-ty/src/display.rs

@@ -1043,7 +1043,11 @@ impl HirDisplay for Ty {
                             module_id,
                             PrefixKind::Plain,
                             false,
-                            ImportPathConfig { prefer_no_std: false, prefer_prelude: true },
+                            ImportPathConfig {
+                                prefer_no_std: false,
+                                prefer_prelude: true,
+                                prefer_absolute: false,
+                            },
                         ) {
                             write!(f, "{}", path.display(f.db.upcast()))?;
                         } else {

src/tools/rust-analyzer/crates/ide-assists/src/assist_config.rs

@@ -15,6 +15,7 @@ pub struct AssistConfig {
     pub insert_use: InsertUseConfig,
     pub prefer_no_std: bool,
     pub prefer_prelude: bool,
+    pub prefer_absolute: bool,
     pub assist_emit_must_use: bool,
     pub term_search_fuel: u64,
     pub term_search_borrowck: bool,

src/tools/rust-analyzer/crates/ide-assists/src/handlers/add_missing_match_arms.rs

@@ -74,6 +74,7 @@ pub(crate) fn add_missing_match_arms(acc: &mut Assists, ctx: &AssistContext<'_>)
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     let module = ctx.sema.scope(expr.syntax())?.module();

src/tools/rust-analyzer/crates/ide-assists/src/handlers/auto_import.rs

@@ -93,6 +93,7 @@ pub(crate) fn auto_import(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     let (import_assets, syntax_under_caret) = find_importable_node(ctx)?;

src/tools/rust-analyzer/crates/ide-assists/src/handlers/bool_to_enum.rs

@@ -340,6 +340,7 @@ fn augment_references_with_imports(
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     references

src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_into_to_from.rs

@@ -47,6 +47,7 @@ pub(crate) fn convert_into_to_from(acc: &mut Assists, ctx: &AssistContext<'_>) -
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     let src_type_path = {

src/tools/rust-analyzer/crates/ide-assists/src/handlers/convert_tuple_return_type_to_struct.rs

@@ -186,6 +186,7 @@ fn augment_references_with_imports(
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     references

src/tools/rust-analyzer/crates/ide-assists/src/handlers/destructure_struct_binding.rs

@@ -90,6 +90,7 @@ fn collect_data(ident_pat: ast::IdentPat, ctx: &AssistContext<'_>) -> Option<Str
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     let module = ctx.sema.scope(ident_pat.syntax())?.module();

src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_function.rs

@@ -216,6 +216,7 @@ pub(crate) fn extract_function(acc: &mut Assists, ctx: &AssistContext<'_>) -> Op
                         ImportPathConfig {
                             prefer_no_std: ctx.config.prefer_no_std,
                             prefer_prelude: ctx.config.prefer_prelude,
+                            prefer_absolute: ctx.config.prefer_absolute,
                         },
                     );
 

src/tools/rust-analyzer/crates/ide-assists/src/handlers/extract_struct_from_enum_variant.rs

@@ -393,6 +393,7 @@ fn process_references(
                     ImportPathConfig {
                         prefer_no_std: ctx.config.prefer_no_std,
                         prefer_prelude: ctx.config.prefer_prelude,
+                        prefer_absolute: ctx.config.prefer_absolute,
                     },
                 );
                 if let Some(mut mod_path) = mod_path {

src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_deref.rs

@@ -64,6 +64,7 @@ fn generate_record_deref(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<(
         ImportPathConfig {
             prefer_no_std: ctx.config.prefer_no_std,
             prefer_prelude: ctx.config.prefer_prelude,
+            prefer_absolute: ctx.config.prefer_absolute,
         },
     )?;
 
@@ -111,6 +112,7 @@ fn generate_tuple_deref(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()
         ImportPathConfig {
             prefer_no_std: ctx.config.prefer_no_std,
             prefer_prelude: ctx.config.prefer_prelude,
+            prefer_absolute: ctx.config.prefer_absolute,
         },
     )?;
 

src/tools/rust-analyzer/crates/ide-assists/src/handlers/generate_new.rs

@@ -65,6 +65,7 @@ pub(crate) fn generate_new(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
                     ImportPathConfig {
                         prefer_no_std: ctx.config.prefer_no_std,
                         prefer_prelude: ctx.config.prefer_prelude,
+                        prefer_absolute: ctx.config.prefer_absolute,
                     },
                 )?;
 

src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_method_call.rs

@@ -53,6 +53,7 @@ pub(crate) fn qualify_method_call(acc: &mut Assists, ctx: &AssistContext<'_>) ->
         ImportPathConfig {
             prefer_no_std: ctx.config.prefer_no_std,
             prefer_prelude: ctx.config.prefer_prelude,
+            prefer_absolute: ctx.config.prefer_absolute,
         },
     )?;
 

src/tools/rust-analyzer/crates/ide-assists/src/handlers/qualify_path.rs

@@ -40,6 +40,7 @@ pub(crate) fn qualify_path(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     let mut proposed_imports: Vec<_> =

src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_derive_with_manual_impl.rs

@@ -89,6 +89,7 @@ pub(crate) fn replace_derive_with_manual_impl(
                 ImportPathConfig {
                     prefer_no_std: ctx.config.prefer_no_std,
                     prefer_prelude: ctx.config.prefer_prelude,
+                    prefer_absolute: ctx.config.prefer_absolute,
                 },
             )
             .as_ref()

src/tools/rust-analyzer/crates/ide-assists/src/handlers/replace_qualified_name_with_use.rs

@@ -70,6 +70,7 @@ pub(crate) fn replace_qualified_name_with_use(
                 ImportPathConfig {
                     prefer_no_std: ctx.config.prefer_no_std,
                     prefer_prelude: ctx.config.prefer_prelude,
+                    prefer_absolute: ctx.config.prefer_absolute,
                 },
             )
         })

src/tools/rust-analyzer/crates/ide-assists/src/handlers/term_search.rs

@@ -60,6 +60,7 @@ pub(crate) fn term_search(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<
                 ImportPathConfig {
                     prefer_no_std: ctx.config.prefer_no_std,
                     prefer_prelude: ctx.config.prefer_prelude,
+                    prefer_absolute: ctx.config.prefer_absolute,
                 },
             )
             .ok()

src/tools/rust-analyzer/crates/ide-assists/src/handlers/toggle_async_sugar.rs

@@ -142,6 +142,7 @@ pub(crate) fn desugar_async_into_impl_future(
         ImportPathConfig {
             prefer_no_std: ctx.config.prefer_no_std,
             prefer_prelude: ctx.config.prefer_prelude,
+            prefer_absolute: ctx.config.prefer_absolute,
         },
     )?;
     let trait_path = trait_path.display(ctx.db());

src/tools/rust-analyzer/crates/ide-assists/src/tests.rs

@@ -30,6 +30,7 @@ pub(crate) const TEST_CONFIG: AssistConfig = AssistConfig {
     },
     prefer_no_std: false,
     prefer_prelude: true,
+    prefer_absolute: false,
     assist_emit_must_use: false,
     term_search_fuel: 400,
     term_search_borrowck: true,
@@ -47,6 +48,7 @@ pub(crate) const TEST_CONFIG_NO_SNIPPET_CAP: AssistConfig = AssistConfig {
     },
     prefer_no_std: false,
     prefer_prelude: true,
+    prefer_absolute: false,
     assist_emit_must_use: false,
     term_search_fuel: 400,
     term_search_borrowck: true,
@@ -64,6 +66,7 @@ pub(crate) const TEST_CONFIG_IMPORT_ONE: AssistConfig = AssistConfig {
     },
     prefer_no_std: false,
     prefer_prelude: true,
+    prefer_absolute: false,
     assist_emit_must_use: false,
     term_search_fuel: 400,
     term_search_borrowck: true,

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

@@ -639,6 +639,7 @@ fn enum_variants_with_paths(
             ImportPathConfig {
                 prefer_no_std: ctx.config.prefer_no_std,
                 prefer_prelude: ctx.config.prefer_prelude,
+                prefer_absolute: ctx.config.prefer_absolute,
             },
         ) {
             // Variants with trivial paths are already added by the existing completion logic,

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

@@ -177,6 +177,7 @@ pub(crate) fn complete_expr_path(
                                 ImportPathConfig {
                                     prefer_no_std: ctx.config.prefer_no_std,
                                     prefer_prelude: ctx.config.prefer_prelude,
+                                    prefer_absolute: ctx.config.prefer_absolute,
                                 },
                             )
                             .filter(|it| it.len() > 1);
@@ -202,6 +203,7 @@ pub(crate) fn complete_expr_path(
                                 ImportPathConfig {
                                     prefer_no_std: ctx.config.prefer_no_std,
                                     prefer_prelude: ctx.config.prefer_prelude,
+                                    prefer_absolute: ctx.config.prefer_absolute,
                                 },
                             )
                             .filter(|it| it.len() > 1);

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

@@ -259,6 +259,7 @@ fn import_on_the_fly(
     let import_cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     import_assets
@@ -309,6 +310,7 @@ fn import_on_the_fly_pat_(
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     import_assets
@@ -354,6 +356,7 @@ fn import_on_the_fly_method(
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     import_assets

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

@@ -63,6 +63,7 @@ pub(crate) fn complete_postfix(
     let cfg = ImportPathConfig {
         prefer_no_std: ctx.config.prefer_no_std,
         prefer_prelude: ctx.config.prefer_prelude,
+        prefer_absolute: ctx.config.prefer_absolute,
     };
 
     if let Some(drop_trait) = ctx.famous_defs().core_ops_Drop() {

src/tools/rust-analyzer/crates/ide-completion/src/config.rs

@@ -22,6 +22,7 @@ pub struct CompletionConfig {
     pub insert_use: InsertUseConfig,
     pub prefer_no_std: bool,
     pub prefer_prelude: bool,
+    pub prefer_absolute: bool,
     pub snippets: Vec<Snippet>,
     pub limit: Option<usize>,
 }

src/tools/rust-analyzer/crates/ide-completion/src/lib.rs

@@ -253,6 +253,7 @@ pub fn resolve_completion_edits(
     let cfg = ImportPathConfig {
         prefer_no_std: config.prefer_no_std,
         prefer_prelude: config.prefer_prelude,
+        prefer_absolute: config.prefer_absolute,
     };
 
     imports.into_iter().for_each(|(full_import_path, imported_name)| {