minor: Simplify

crates/base-db/src/fixture.rs

@@ -408,6 +408,7 @@ fn parse_crate(crate_str: String) -> (String, CrateOrigin, Option<String>) {
     } else {
         let crate_origin = match &*crate_str {
             "std" => CrateOrigin::Lang(LangCrateOrigin::Std),
+            "core" => CrateOrigin::Lang(LangCrateOrigin::Core),
             _ => CrateOrigin::CratesIo { repo: None },
         };
         (crate_str, crate_origin, None)

crates/hir-def/src/macro_expansion_tests/builtin_derive_macro.rs

@@ -25,6 +25,7 @@ fn test_copy_expand_in_core() {
     cov_mark::check!(test_copy_expand_in_core);
     check(
         r#"
+//- /lib.rs crate:core
 #[rustc_builtin_macro]
 macro derive {}
 #[rustc_builtin_macro]

crates/hir-expand/src/builtin_derive_macro.rs

@@ -1,5 +1,6 @@
 //! Builtin derives.
 
+use base_db::{CrateOrigin, LangCrateOrigin};
 use tracing::debug;
 
 use syntax::{
@@ -160,14 +161,11 @@ fn find_builtin_crate(db: &dyn AstDatabase, id: MacroCallId) -> tt::TokenTree {
     let cg = db.crate_graph();
     let krate = db.lookup_intern_macro_call(id).krate;
 
-    // XXX
-    //  All crates except core itself should have a dependency on core,
-    //  We detect `core` by seeing whether it doesn't have such a dependency.
-    let tt = if cg[krate].dependencies.iter().any(|dep| &*dep.name == "core") {
-        quote! { core }
-    } else {
+    let tt = if matches!(cg[krate].origin, CrateOrigin::Lang(LangCrateOrigin::Core)) {
         cov_mark::hit!(test_copy_expand_in_core);
         quote! { crate }
+    } else {
+        quote! { core }
     };
 
     tt.token_trees[0].clone()

crates/ide-db/src/defs.rs

@@ -7,9 +7,9 @@
 
 use arrayvec::ArrayVec;
 use hir::{
-    Adt, AsAssocItem, AssocItem, BuiltinAttr, BuiltinType, Const, Field, Function, GenericParam,
-    HasVisibility, Impl, ItemInNs, Label, Local, Macro, Module, ModuleDef, Name, PathResolution,
-    Semantics, Static, ToolModule, Trait, TypeAlias, Variant, Visibility,
+    Adt, AsAssocItem, AssocItem, BuiltinAttr, BuiltinType, Const, Crate, Field, Function,
+    GenericParam, HasVisibility, Impl, ItemInNs, Label, Local, Macro, Module, ModuleDef, Name,
+    PathResolution, Semantics, Static, ToolModule, Trait, TypeAlias, Variant, Visibility,
 };
 use stdx::impl_from;
 use syntax::{
@@ -46,6 +46,13 @@ impl Definition {
         self.module(db).map(|it| it.path_to_root(db).into_iter().rev())
     }
 
+    pub fn krate(&self, db: &RootDatabase) -> Option<Crate> {
+        Some(match self {
+            Definition::Module(m) => m.krate(),
+            _ => self.module(db)?.krate(),
+        })
+    }
+
     pub fn module(&self, db: &RootDatabase) -> Option<Module> {
         let module = match self {
             Definition::Macro(it) => it.module(db),

crates/ide/src/doc_links.rs

@@ -293,7 +293,7 @@ fn broken_link_clone_cb<'a>(link: BrokenLink<'a>) -> Option<(CowStr<'a>, CowStr<
 fn get_doc_link(db: &RootDatabase, def: Definition) -> Option<String> {
     let (target, file, frag) = filename_and_frag_for_def(db, def)?;
 
-    let krate = crate_of_def(db, target)?;
+    let krate = target.krate(db)?;
     let mut url = get_doc_base_url(db, krate)?;
 
     if let Some(path) = mod_path_of_def(db, target) {
@@ -315,7 +315,7 @@ fn rewrite_intra_doc_link(
     let (link, ns) = parse_intra_doc_link(target);
 
     let resolved = resolve_doc_path_for_def(db, def, link, ns)?;
-    let krate = crate_of_def(db, resolved)?;
+    let krate = resolved.krate(db)?;
     let mut url = get_doc_base_url(db, krate)?;
 
     let (_, file, frag) = filename_and_frag_for_def(db, resolved)?;
@@ -335,7 +335,7 @@ fn rewrite_url_link(db: &RootDatabase, def: Definition, target: &str) -> Option<
         return None;
     }
 
-    let krate = crate_of_def(db, def)?;
+    let krate = def.krate(db)?;
     let mut url = get_doc_base_url(db, krate)?;
     let (def, file, frag) = filename_and_frag_for_def(db, def)?;
 
@@ -348,15 +348,6 @@ fn rewrite_url_link(db: &RootDatabase, def: Definition, target: &str) -> Option<
     url.join(target).ok().map(Into::into)
 }
 
-fn crate_of_def(db: &RootDatabase, def: Definition) -> Option<Crate> {
-    let krate = match def {
-        // Definition::module gives back the parent module, we don't want that as it fails for root modules
-        Definition::Module(module) => module.krate(),
-        def => def.module(db)?.krate(),
-    };
-    Some(krate)
-}
-
 fn mod_path_of_def(db: &RootDatabase, def: Definition) -> Option<String> {
     def.canonical_module_path(db).map(|it| {
         let mut path = String::new();

crates/ide/src/syntax_highlighting/highlight.rs

@@ -466,10 +466,7 @@ fn highlight_def(sema: &Semantics<RootDatabase>, krate: hir::Crate, def: Definit
         Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
     };
 
-    let def_crate = def.module(db).map(hir::Module::krate).or_else(|| match def {
-        Definition::Module(module) => Some(module.krate()),
-        _ => None,
-    });
+    let def_crate = def.krate(db);
     let is_from_other_crate = def_crate != Some(krate);
     let is_from_builtin_crate = def_crate.map_or(false, |def_crate| def_crate.is_builtin(db));
     let is_builtin_type = matches!(def, Definition::BuiltinType(_));