From 47d7434dde215460fc95916f2703c6925f58dcce Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Tue, 18 May 2021 14:42:41 +0300 Subject: internal: replace AstTransformer with mutable syntax trees --- crates/ide_assists/src/ast_transform.rs | 236 ++++++++++++-------------------- crates/ide_assists/src/utils.rs | 22 +-- 2 files changed, 104 insertions(+), 154 deletions(-) (limited to 'crates/ide_assists') diff --git a/crates/ide_assists/src/ast_transform.rs b/crates/ide_assists/src/ast_transform.rs index e5ae718c9..5d9cc5551 100644 --- a/crates/ide_assists/src/ast_transform.rs +++ b/crates/ide_assists/src/ast_transform.rs @@ -1,31 +1,12 @@ //! `AstTransformer`s are functions that replace nodes in an AST and can be easily combined. -use hir::{HirDisplay, PathResolution, SemanticsScope}; +use hir::{HirDisplay, SemanticsScope}; use ide_db::helpers::mod_path_to_ast; use rustc_hash::FxHashMap; use syntax::{ ast::{self, AstNode}, - ted, SyntaxNode, + ted, }; -pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: &N) { - let mut skip_to = None; - for event in node.syntax().preorder() { - match event { - syntax::WalkEvent::Enter(node) if skip_to.is_none() => { - skip_to = transformer.get_substitution(&node, transformer).zip(Some(node)); - } - syntax::WalkEvent::Enter(_) => (), - syntax::WalkEvent::Leave(node) => match &skip_to { - Some((replacement, skip_target)) if *skip_target == node => { - ted::replace(node, replacement.clone_for_update()); - skip_to.take(); - } - _ => (), - }, - } - } -} - /// `AstTransform` helps with applying bulk transformations to syntax nodes. /// /// This is mostly useful for IDE code generation. If you paste some existing @@ -35,8 +16,8 @@ pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: &N) { /// /// ``` /// mod x { -/// pub struct A; -/// pub trait T { fn foo(&self, _: U) -> A; } +/// pub struct A; +/// pub trait T { fn foo(&self, _: U) -> A; } /// } /// /// mod y { @@ -45,7 +26,7 @@ pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: &N) { /// 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 {} +/// fn foo(&self, _: ()) -> x::A<()> {} /// } /// } /// ``` @@ -54,49 +35,27 @@ pub fn apply<'a, N: AstNode>(transformer: &dyn AstTransform<'a>, node: &N) { /// `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))) - } +pub(crate) struct AstTransform<'a> { + pub(crate) subst: (hir::Trait, ast::Impl), + pub(crate) target_scope: &'a SemanticsScope<'a>, + pub(crate) source_scope: &'a SemanticsScope<'a>, } -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)) +impl<'a> AstTransform<'a> { + pub(crate) fn apply(&self, item: ast::AssocItem) { + if let Some(ctx) = self.build_ctx() { + ctx.apply(item) + } } -} - -pub struct SubstituteTypeParams<'a> { - source_scope: &'a SemanticsScope<'a>, - substs: FxHashMap, -} + fn build_ctx(&self) -> Option> { + let db = self.source_scope.db; + let target_module = self.target_scope.module()?; + let source_module = self.source_scope.module()?; -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 = get_syntactic_substs(self.subst.1.clone()).unwrap_or_default(); + let generic_def: hir::GenericDef = self.subst.0.into(); let substs_by_param: FxHashMap<_, _> = generic_def - .type_params(source_scope.db) + .type_params(db) .into_iter() // this is a trait impl, so we need to skip the first type parameter -- this is a bit hacky .skip(1) @@ -110,109 +69,96 @@ impl<'a> SubstituteTypeParams<'a> { .filter_map(|(k, v)| match v { Some(v) => Some((k, v)), None => { - let default = k.default(source_scope.db)?; + let default = k.default(db)?; Some(( k, - ast::make::ty( - &default - .display_source_code(source_scope.db, source_scope.module()?.into()) - .ok()?, - ), + ast::make::ty(&default.display_source_code(db, source_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) - } + let res = Ctx { substs: substs_by_param, target_module, source_scope: self.source_scope }; + Some(res) } } -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>, +struct Ctx<'a> { + substs: FxHashMap, + target_module: hir::Module, 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> Ctx<'a> { + fn apply(&self, item: ast::AssocItem) { + for event in item.syntax().preorder() { + let node = match event { + syntax::WalkEvent::Enter(_) => continue, + syntax::WalkEvent::Leave(it) => it, + }; + if let Some(path) = ast::Path::cast(node.clone()) { + self.transform_path(path); + } + } } -} - -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() { + fn transform_path(&self, path: ast::Path) -> Option<()> { + if path.qualifier().is_some() { + return None; + } + if path.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()); - if let Some(type_args) = type_args { - apply(recur, &type_args); - let last_segment = path.segment().unwrap(); - path = path.with_segment(last_segment.with_generic_args(type_args)) - } + let resolution = self.source_scope.speculative_resolve(&path)?; - Some(path.syntax().clone()) + match resolution { + hir::PathResolution::TypeParam(tp) => { + if let Some(subst) = self.substs.get(&tp) { + ted::replace(path.syntax(), subst.clone_subtree().clone_for_update().syntax()) + } + } + hir::PathResolution::Def(def) => { + let found_path = + self.target_module.find_use_path(self.source_scope.db.upcast(), def)?; + let res = mod_path_to_ast(&found_path).clone_for_update(); + if let Some(args) = path.segment().and_then(|it| it.generic_arg_list()) { + if let Some(segment) = res.segment() { + let old = segment.get_or_create_generic_arg_list(); + ted::replace(old.syntax(), args.clone_subtree().syntax().clone_for_update()) + } + } + ted::replace(path.syntax(), res.syntax()) } - PathResolution::Local(_) - | PathResolution::TypeParam(_) - | PathResolution::SelfType(_) - | PathResolution::ConstParam(_) => None, - PathResolution::Macro(_) => None, - PathResolution::AssocItem(_) => None, + hir::PathResolution::Local(_) + | hir::PathResolution::ConstParam(_) + | hir::PathResolution::SelfType(_) + | hir::PathResolution::Macro(_) + | hir::PathResolution::AssocItem(_) => (), } + Some(()) } } + +// 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) +} diff --git a/crates/ide_assists/src/utils.rs b/crates/ide_assists/src/utils.rs index fc7caee04..2e79a3aed 100644 --- a/crates/ide_assists/src/utils.rs +++ b/crates/ide_assists/src/utils.rs @@ -24,7 +24,7 @@ use syntax::{ use crate::{ assist_context::{AssistBuilder, AssistContext}, - ast_transform::{self, AstTransform, QualifyPaths, SubstituteTypeParams}, + ast_transform::AstTransform, }; pub(crate) fn unwrap_trivial_block(block: ast::BlockExpr) -> ast::Expr { @@ -132,14 +132,18 @@ pub fn add_trait_assoc_items_to_impl( target_scope: hir::SemanticsScope, ) -> (ast::Impl, ast::AssocItem) { let source_scope = sema.scope_for_def(trait_); - let ast_transform = QualifyPaths::new(&target_scope, &source_scope) - .or(SubstituteTypeParams::for_trait_impl(&source_scope, trait_, impl_.clone())); - - let items = items - .into_iter() - .map(|it| it.clone_for_update()) - .inspect(|it| ast_transform::apply(&*ast_transform, it)) - .map(|it| edit::remove_attrs_and_docs(&it).clone_subtree().clone_for_update()); + + let transform = AstTransform { + subst: (trait_, impl_.clone()), + source_scope: &source_scope, + target_scope: &target_scope, + }; + + let items = items.into_iter().map(|assoc_item| { + let assoc_item = assoc_item.clone_for_update(); + transform.apply(assoc_item.clone()); + edit::remove_attrs_and_docs(&assoc_item).clone_subtree().clone_for_update() + }); let res = impl_.clone_for_update(); -- cgit v1.2.3