From e4756cb4f6e66097638b9d101589358976be2ba8 Mon Sep 17 00:00:00 2001 From: Chetan Khilosiya Date: Tue, 23 Feb 2021 00:17:48 +0530 Subject: 7526: Rename crate assists to ide_assists. --- crates/assists/src/ast_transform.rs | 213 ------------------------------------ 1 file changed, 213 deletions(-) delete mode 100644 crates/assists/src/ast_transform.rs (limited to 'crates/assists/src/ast_transform.rs') diff --git a/crates/assists/src/ast_transform.rs b/crates/assists/src/ast_transform.rs deleted file mode 100644 index 4a3ed7783..000000000 --- a/crates/assists/src/ast_transform.rs +++ /dev/null @@ -1,213 +0,0 @@ -//! `AstTransformer`s are functions that replace nodes in an AST and can be easily combined. -use hir::{HirDisplay, PathResolution, SemanticsScope}; -use ide_db::helpers::mod_path_to_ast; -use rustc_hash::FxHashMap; -use syntax::{ - algo::SyntaxRewriter, - ast::{self, AstNode}, - SyntaxNode, -}; - -pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: N) -> N { - SyntaxRewriter::from_fn(|element| match element { - syntax::SyntaxElement::Node(n) => { - let replacement = transformer.get_substitution(&n, transformer)?; - Some(replacement.into()) - } - _ => None, - }) - .rewrite_ast(&node) -} - -/// `AstTransform` helps with applying bulk transformations to syntax nodes. -/// -/// This is mostly useful for IDE code generation. If you paste some existing -/// code into a new context (for example, to add method overrides to an `impl` -/// block), you generally want to appropriately qualify the names, and sometimes -/// you might want to substitute generic parameters as well: -/// -/// ``` -/// mod x { -/// pub struct A; -/// pub trait T { fn foo(&self, _: U) -> A; } -/// } -/// -/// mod y { -/// use x::T; -/// -/// impl T<()> for () { -/// // If we invoke **Add Missing Members** here, we want to copy-paste `foo`. -/// // But we want a slightly-modified version of it: -/// fn foo(&self, _: ()) -> x::A {} -/// } -/// } -/// ``` -/// -/// So, a single `AstTransform` describes such function from `SyntaxNode` to -/// `SyntaxNode`. Note that the API here is a bit too high-order and high-brow. -/// We'd want to somehow express this concept simpler, but so far nobody got to -/// simplifying this! -pub trait AstTransform<'a> { - fn get_substitution( - &self, - node: &SyntaxNode, - recur: &dyn AstTransform<'a>, - ) -> Option; - - fn or + 'a>(self, other: T) -> Box + 'a> - where - Self: Sized + 'a, - { - Box::new(Or(Box::new(self), Box::new(other))) - } -} - -struct Or<'a>(Box + 'a>, Box + 'a>); - -impl<'a> AstTransform<'a> for Or<'a> { - fn get_substitution( - &self, - node: &SyntaxNode, - recur: &dyn AstTransform<'a>, - ) -> Option { - self.0.get_substitution(node, recur).or_else(|| self.1.get_substitution(node, recur)) - } -} - -pub struct SubstituteTypeParams<'a> { - source_scope: &'a SemanticsScope<'a>, - substs: FxHashMap, -} - -impl<'a> SubstituteTypeParams<'a> { - pub fn for_trait_impl( - source_scope: &'a SemanticsScope<'a>, - // FIXME: there's implicit invariant that `trait_` and `source_scope` match... - trait_: hir::Trait, - impl_def: ast::Impl, - ) -> SubstituteTypeParams<'a> { - let substs = get_syntactic_substs(impl_def).unwrap_or_default(); - let generic_def: hir::GenericDef = trait_.into(); - let substs_by_param: FxHashMap<_, _> = generic_def - .type_params(source_scope.db) - .into_iter() - // this is a trait impl, so we need to skip the first type parameter -- this is a bit hacky - .skip(1) - // The actual list of trait type parameters may be longer than the one - // used in the `impl` block due to trailing default type parameters. - // For that case we extend the `substs` with an empty iterator so we - // can still hit those trailing values and check if they actually have - // a default type. If they do, go for that type from `hir` to `ast` so - // the resulting change can be applied correctly. - .zip(substs.into_iter().map(Some).chain(std::iter::repeat(None))) - .filter_map(|(k, v)| match v { - Some(v) => Some((k, v)), - None => { - let default = k.default(source_scope.db)?; - Some(( - k, - ast::make::ty( - &default - .display_source_code(source_scope.db, source_scope.module()?.into()) - .ok()?, - ), - )) - } - }) - .collect(); - return SubstituteTypeParams { source_scope, substs: substs_by_param }; - - // FIXME: It would probably be nicer if we could get this via HIR (i.e. get the - // trait ref, and then go from the types in the substs back to the syntax). - fn get_syntactic_substs(impl_def: ast::Impl) -> Option> { - let target_trait = impl_def.trait_()?; - let path_type = match target_trait { - ast::Type::PathType(path) => path, - _ => return None, - }; - let generic_arg_list = path_type.path()?.segment()?.generic_arg_list()?; - - let mut result = Vec::new(); - for generic_arg in generic_arg_list.generic_args() { - match generic_arg { - ast::GenericArg::TypeArg(type_arg) => result.push(type_arg.ty()?), - ast::GenericArg::AssocTypeArg(_) - | ast::GenericArg::LifetimeArg(_) - | ast::GenericArg::ConstArg(_) => (), - } - } - - Some(result) - } - } -} - -impl<'a> AstTransform<'a> for SubstituteTypeParams<'a> { - fn get_substitution( - &self, - node: &SyntaxNode, - _recur: &dyn AstTransform<'a>, - ) -> Option { - let type_ref = ast::Type::cast(node.clone())?; - let path = match &type_ref { - ast::Type::PathType(path_type) => path_type.path()?, - _ => return None, - }; - let resolution = self.source_scope.speculative_resolve(&path)?; - match resolution { - hir::PathResolution::TypeParam(tp) => Some(self.substs.get(&tp)?.syntax().clone()), - _ => None, - } - } -} - -pub struct QualifyPaths<'a> { - target_scope: &'a SemanticsScope<'a>, - source_scope: &'a SemanticsScope<'a>, -} - -impl<'a> QualifyPaths<'a> { - pub fn new(target_scope: &'a SemanticsScope<'a>, source_scope: &'a SemanticsScope<'a>) -> Self { - Self { target_scope, source_scope } - } -} - -impl<'a> AstTransform<'a> for QualifyPaths<'a> { - fn get_substitution( - &self, - node: &SyntaxNode, - recur: &dyn AstTransform<'a>, - ) -> Option { - // FIXME handle value ns? - let from = self.target_scope.module()?; - let p = ast::Path::cast(node.clone())?; - if p.segment().and_then(|s| s.param_list()).is_some() { - // don't try to qualify `Fn(Foo) -> Bar` paths, they are in prelude anyway - return None; - } - let resolution = self.source_scope.speculative_resolve(&p)?; - match resolution { - PathResolution::Def(def) => { - let found_path = from.find_use_path(self.source_scope.db.upcast(), def)?; - let mut path = mod_path_to_ast(&found_path); - - let type_args = p - .segment() - .and_then(|s| s.generic_arg_list()) - .map(|arg_list| apply(recur, arg_list)); - if let Some(type_args) = type_args { - let last_segment = path.segment().unwrap(); - path = path.with_segment(last_segment.with_generic_args(type_args)) - } - - Some(path.syntax().clone()) - } - PathResolution::Local(_) - | PathResolution::TypeParam(_) - | PathResolution::SelfType(_) - | PathResolution::ConstParam(_) => None, - PathResolution::Macro(_) => None, - PathResolution::AssocItem(_) => None, - } - } -} -- cgit v1.2.3