bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide_db/src/helpers/famous_defs.rs')
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diff --git a/crates/ide_db/src/helpers/famous_defs.rs b/crates/ide_db/src/helpers/famous_defs.rs
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+++ b/crates/ide_db/src/helpers/famous_defs.rs
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+//! See [`FamousDefs`].
+use hir::{Crate, Enum, Module, ScopeDef, Semantics, Trait};
+
+use crate::RootDatabase;
+
+/// Helps with finding well-know things inside the standard library. This is
+/// somewhat similar to the known paths infra inside hir, but it different; We
+/// want to make sure that IDE specific paths don't become interesting inside
+/// the compiler itself as well.
+///
+/// Note that, by default, rust-analyzer tests **do not** include core or std
+/// libraries. If you are writing tests for functionality using [`FamousDefs`],
+/// you'd want to include minicore (see `test_utils::MiniCore`) declaration at
+/// the start of your tests:
+///
+/// ```
+/// //- minicore: iterator, ord, derive
+/// ```
+pub struct FamousDefs<'a, 'b>(pub &'a Semantics<'b, RootDatabase>, pub Option<Crate>);
+
+#[allow(non_snake_case)]
+impl FamousDefs<'_, '_> {
+ pub fn std(&self) -> Option<Crate> {
+ self.find_crate("std")
+ }
+
+ pub fn core(&self) -> Option<Crate> {
+ self.find_crate("core")
+ }
+
+ pub fn core_cmp_Ord(&self) -> Option<Trait> {
+ self.find_trait("core:cmp:Ord")
+ }
+
+ pub fn core_convert_From(&self) -> Option<Trait> {
+ self.find_trait("core:convert:From")
+ }
+
+ pub fn core_convert_Into(&self) -> Option<Trait> {
+ self.find_trait("core:convert:Into")
+ }
+
+ pub fn core_option_Option(&self) -> Option<Enum> {
+ self.find_enum("core:option:Option")
+ }
+
+ pub fn core_result_Result(&self) -> Option<Enum> {
+ self.find_enum("core:result:Result")
+ }
+
+ pub fn core_default_Default(&self) -> Option<Trait> {
+ self.find_trait("core:default:Default")
+ }
+
+ pub fn core_iter_Iterator(&self) -> Option<Trait> {
+ self.find_trait("core:iter:traits:iterator:Iterator")
+ }
+
+ pub fn core_iter_IntoIterator(&self) -> Option<Trait> {
+ self.find_trait("core:iter:traits:collect:IntoIterator")
+ }
+
+ pub fn core_iter(&self) -> Option<Module> {
+ self.find_module("core:iter")
+ }
+
+ pub fn core_ops_Deref(&self) -> Option<Trait> {
+ self.find_trait("core:ops:Deref")
+ }
+
+ fn find_trait(&self, path: &str) -> Option<Trait> {
+ match self.find_def(path)? {
+ hir::ScopeDef::ModuleDef(hir::ModuleDef::Trait(it)) => Some(it),
+ _ => None,
+ }
+ }
+
+ fn find_enum(&self, path: &str) -> Option<Enum> {
+ match self.find_def(path)? {
+ hir::ScopeDef::ModuleDef(hir::ModuleDef::Adt(hir::Adt::Enum(it))) => Some(it),
+ _ => None,
+ }
+ }
+
+ fn find_module(&self, path: &str) -> Option<Module> {
+ match self.find_def(path)? {
+ hir::ScopeDef::ModuleDef(hir::ModuleDef::Module(it)) => Some(it),
+ _ => None,
+ }
+ }
+
+ fn find_crate(&self, name: &str) -> Option<Crate> {
+ let krate = self.1?;
+ let db = self.0.db;
+ let res =
+ krate.dependencies(db).into_iter().find(|dep| dep.name.to_string() == name)?.krate;
+ Some(res)
+ }
+
+ fn find_def(&self, path: &str) -> Option<ScopeDef> {
+ let db = self.0.db;
+ let mut path = path.split(':');
+ let trait_ = path.next_back()?;
+ let std_crate = path.next()?;
+ let std_crate = self.find_crate(std_crate)?;
+ let mut module = std_crate.root_module(db);
+ for segment in path {
+ module = module.children(db).find_map(|child| {
+ let name = child.name(db)?;
+ if name.to_string() == segment {
+ Some(child)
+ } else {
+ None
+ }
+ })?;
+ }
+ let def =
+ module.scope(db, None).into_iter().find(|(name, _def)| name.to_string() == trait_)?.1;
+ Some(def)
+ }
+}