From fc34403018079ea053f26d0a31b7517053c7dd8c Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Thu, 13 Aug 2020 17:33:38 +0200 Subject: Rename ra_assists -> assists --- crates/ra_assists/src/utils/insert_use.rs | 547 ------------------------------ 1 file changed, 547 deletions(-) delete mode 100644 crates/ra_assists/src/utils/insert_use.rs (limited to 'crates/ra_assists/src/utils/insert_use.rs') diff --git a/crates/ra_assists/src/utils/insert_use.rs b/crates/ra_assists/src/utils/insert_use.rs deleted file mode 100644 index 50a62ee82..000000000 --- a/crates/ra_assists/src/utils/insert_use.rs +++ /dev/null @@ -1,547 +0,0 @@ -//! Handle syntactic aspects of inserting a new `use`. -// FIXME: rewrite according to the plan, outlined in -// https://github.com/rust-analyzer/rust-analyzer/issues/3301#issuecomment-592931553 - -use std::iter::successors; - -use either::Either; -use hir::{self, ModPath}; -use syntax::{ - ast::{self, NameOwner, VisibilityOwner}, - AstNode, AstToken, Direction, SmolStr, - SyntaxKind::{PATH, PATH_SEGMENT}, - SyntaxNode, SyntaxToken, T, -}; -use text_edit::TextEditBuilder; - -use crate::assist_context::AssistContext; - -/// Determines the containing syntax node in which to insert a `use` statement affecting `position`. -pub(crate) fn find_insert_use_container( - position: &SyntaxNode, - ctx: &AssistContext, -) -> Option> { - ctx.sema.ancestors_with_macros(position.clone()).find_map(|n| { - if let Some(module) = ast::Module::cast(n.clone()) { - return module.item_list().map(|it| Either::Left(it)); - } - Some(Either::Right(ast::SourceFile::cast(n)?)) - }) -} - -/// Creates and inserts a use statement for the given path to import. -/// The use statement is inserted in the scope most appropriate to the -/// the cursor position given, additionally merged with the existing use imports. -pub(crate) fn insert_use_statement( - // Ideally the position of the cursor, used to - position: &SyntaxNode, - path_to_import: &ModPath, - ctx: &AssistContext, - builder: &mut TextEditBuilder, -) { - let target = path_to_import.to_string().split("::").map(SmolStr::new).collect::>(); - let container = find_insert_use_container(position, ctx); - - if let Some(container) = container { - let syntax = container.either(|l| l.syntax().clone(), |r| r.syntax().clone()); - let action = best_action_for_target(syntax, position.clone(), &target); - make_assist(&action, &target, builder); - } -} - -fn collect_path_segments_raw( - segments: &mut Vec, - mut path: ast::Path, -) -> Option { - let oldlen = segments.len(); - loop { - let mut children = path.syntax().children_with_tokens(); - let (first, second, third) = ( - children.next().map(|n| (n.clone(), n.kind())), - children.next().map(|n| (n.clone(), n.kind())), - children.next().map(|n| (n.clone(), n.kind())), - ); - match (first, second, third) { - (Some((subpath, PATH)), Some((_, T![::])), Some((segment, PATH_SEGMENT))) => { - path = ast::Path::cast(subpath.as_node()?.clone())?; - segments.push(ast::PathSegment::cast(segment.as_node()?.clone())?); - } - (Some((segment, PATH_SEGMENT)), _, _) => { - segments.push(ast::PathSegment::cast(segment.as_node()?.clone())?); - break; - } - (_, _, _) => return None, - } - } - // We need to reverse only the new added segments - let only_new_segments = segments.split_at_mut(oldlen).1; - only_new_segments.reverse(); - Some(segments.len() - oldlen) -} - -fn fmt_segments_raw(segments: &[SmolStr], buf: &mut String) { - let mut iter = segments.iter(); - if let Some(s) = iter.next() { - buf.push_str(s); - } - for s in iter { - buf.push_str("::"); - buf.push_str(s); - } -} - -/// Returns the number of common segments. -fn compare_path_segments(left: &[SmolStr], right: &[ast::PathSegment]) -> usize { - left.iter().zip(right).take_while(|(l, r)| compare_path_segment(l, r)).count() -} - -fn compare_path_segment(a: &SmolStr, b: &ast::PathSegment) -> bool { - if let Some(kb) = b.kind() { - match kb { - ast::PathSegmentKind::Name(nameref_b) => a == nameref_b.text(), - ast::PathSegmentKind::SelfKw => a == "self", - ast::PathSegmentKind::SuperKw => a == "super", - ast::PathSegmentKind::CrateKw => a == "crate", - ast::PathSegmentKind::Type { .. } => false, // not allowed in imports - } - } else { - false - } -} - -fn compare_path_segment_with_name(a: &SmolStr, b: &ast::Name) -> bool { - a == b.text() -} - -#[derive(Clone, Debug)] -enum ImportAction { - Nothing, - // Add a brand new use statement. - AddNewUse { - anchor: Option, // anchor node - add_after_anchor: bool, - }, - - // To split an existing use statement creating a nested import. - AddNestedImport { - // how may segments matched with the target path - common_segments: usize, - path_to_split: ast::Path, - // the first segment of path_to_split we want to add into the new nested list - first_segment_to_split: Option, - // Wether to add 'self' in addition to the target path - add_self: bool, - }, - // To add the target path to an existing nested import tree list. - AddInTreeList { - common_segments: usize, - // The UseTreeList where to add the target path - tree_list: ast::UseTreeList, - add_self: bool, - }, -} - -impl ImportAction { - fn add_new_use(anchor: Option, add_after_anchor: bool) -> Self { - ImportAction::AddNewUse { anchor, add_after_anchor } - } - - fn add_nested_import( - common_segments: usize, - path_to_split: ast::Path, - first_segment_to_split: Option, - add_self: bool, - ) -> Self { - ImportAction::AddNestedImport { - common_segments, - path_to_split, - first_segment_to_split, - add_self, - } - } - - fn add_in_tree_list( - common_segments: usize, - tree_list: ast::UseTreeList, - add_self: bool, - ) -> Self { - ImportAction::AddInTreeList { common_segments, tree_list, add_self } - } - - fn better(left: ImportAction, right: ImportAction) -> ImportAction { - if left.is_better(&right) { - left - } else { - right - } - } - - fn is_better(&self, other: &ImportAction) -> bool { - match (self, other) { - (ImportAction::Nothing, _) => true, - (ImportAction::AddInTreeList { .. }, ImportAction::Nothing) => false, - ( - ImportAction::AddNestedImport { common_segments: n, .. }, - ImportAction::AddInTreeList { common_segments: m, .. }, - ) - | ( - ImportAction::AddInTreeList { common_segments: n, .. }, - ImportAction::AddNestedImport { common_segments: m, .. }, - ) - | ( - ImportAction::AddInTreeList { common_segments: n, .. }, - ImportAction::AddInTreeList { common_segments: m, .. }, - ) - | ( - ImportAction::AddNestedImport { common_segments: n, .. }, - ImportAction::AddNestedImport { common_segments: m, .. }, - ) => n > m, - (ImportAction::AddInTreeList { .. }, _) => true, - (ImportAction::AddNestedImport { .. }, ImportAction::Nothing) => false, - (ImportAction::AddNestedImport { .. }, _) => true, - (ImportAction::AddNewUse { .. }, _) => false, - } - } -} - -// Find out the best ImportAction to import target path against current_use_tree. -// If current_use_tree has a nested import the function gets called recursively on every UseTree inside a UseTreeList. -fn walk_use_tree_for_best_action( - current_path_segments: &mut Vec, // buffer containing path segments - current_parent_use_tree_list: Option, // will be Some value if we are in a nested import - current_use_tree: ast::UseTree, // the use tree we are currently examinating - target: &[SmolStr], // the path we want to import -) -> ImportAction { - // We save the number of segments in the buffer so we can restore the correct segments - // before returning. Recursive call will add segments so we need to delete them. - let prev_len = current_path_segments.len(); - - let tree_list = current_use_tree.use_tree_list(); - let alias = current_use_tree.rename(); - - let path = match current_use_tree.path() { - Some(path) => path, - None => { - // If the use item don't have a path, it means it's broken (syntax error) - return ImportAction::add_new_use( - current_use_tree - .syntax() - .ancestors() - .find_map(ast::Use::cast) - .map(|it| it.syntax().clone()), - true, - ); - } - }; - - // This can happen only if current_use_tree is a direct child of a UseItem - if let Some(name) = alias.and_then(|it| it.name()) { - if compare_path_segment_with_name(&target[0], &name) { - return ImportAction::Nothing; - } - } - - collect_path_segments_raw(current_path_segments, path.clone()); - - // We compare only the new segments added in the line just above. - // The first prev_len segments were already compared in 'parent' recursive calls. - let left = target.split_at(prev_len).1; - let right = current_path_segments.split_at(prev_len).1; - let common = compare_path_segments(left, &right); - let mut action = match common { - 0 => ImportAction::add_new_use( - // e.g: target is std::fmt and we can have - // use foo::bar - // We add a brand new use statement - current_use_tree - .syntax() - .ancestors() - .find_map(ast::Use::cast) - .map(|it| it.syntax().clone()), - true, - ), - common if common == left.len() && left.len() == right.len() => { - // e.g: target is std::fmt and we can have - // 1- use std::fmt; - // 2- use std::fmt::{ ... } - if let Some(list) = tree_list { - // In case 2 we need to add self to the nested list - // unless it's already there - let has_self = list.use_trees().map(|it| it.path()).any(|p| { - p.and_then(|it| it.segment()) - .and_then(|it| it.kind()) - .filter(|k| *k == ast::PathSegmentKind::SelfKw) - .is_some() - }); - - if has_self { - ImportAction::Nothing - } else { - ImportAction::add_in_tree_list(current_path_segments.len(), list, true) - } - } else { - // Case 1 - ImportAction::Nothing - } - } - common if common != left.len() && left.len() == right.len() => { - // e.g: target is std::fmt and we have - // use std::io; - // We need to split. - let segments_to_split = current_path_segments.split_at(prev_len + common).1; - ImportAction::add_nested_import( - prev_len + common, - path, - Some(segments_to_split[0].clone()), - false, - ) - } - common if common == right.len() && left.len() > right.len() => { - // e.g: target is std::fmt and we can have - // 1- use std; - // 2- use std::{ ... }; - - // fallback action - let mut better_action = ImportAction::add_new_use( - current_use_tree - .syntax() - .ancestors() - .find_map(ast::Use::cast) - .map(|it| it.syntax().clone()), - true, - ); - if let Some(list) = tree_list { - // Case 2, check recursively if the path is already imported in the nested list - for u in list.use_trees() { - let child_action = walk_use_tree_for_best_action( - current_path_segments, - Some(list.clone()), - u, - target, - ); - if child_action.is_better(&better_action) { - better_action = child_action; - if let ImportAction::Nothing = better_action { - return better_action; - } - } - } - } else { - // Case 1, split adding self - better_action = ImportAction::add_nested_import(prev_len + common, path, None, true) - } - better_action - } - common if common == left.len() && left.len() < right.len() => { - // e.g: target is std::fmt and we can have - // use std::fmt::Debug; - let segments_to_split = current_path_segments.split_at(prev_len + common).1; - ImportAction::add_nested_import( - prev_len + common, - path, - Some(segments_to_split[0].clone()), - true, - ) - } - common if common < left.len() && common < right.len() => { - // e.g: target is std::fmt::nested::Debug - // use std::fmt::Display - let segments_to_split = current_path_segments.split_at(prev_len + common).1; - ImportAction::add_nested_import( - prev_len + common, - path, - Some(segments_to_split[0].clone()), - false, - ) - } - _ => unreachable!(), - }; - - // If we are inside a UseTreeList adding a use statement become adding to the existing - // tree list. - action = match (current_parent_use_tree_list, action.clone()) { - (Some(use_tree_list), ImportAction::AddNewUse { .. }) => { - ImportAction::add_in_tree_list(prev_len, use_tree_list, false) - } - (_, _) => action, - }; - - // We remove the segments added - current_path_segments.truncate(prev_len); - action -} - -fn best_action_for_target( - container: SyntaxNode, - anchor: SyntaxNode, - target: &[SmolStr], -) -> ImportAction { - let mut storage = Vec::with_capacity(16); // this should be the only allocation - let best_action = container - .children() - .filter_map(ast::Use::cast) - .filter(|u| u.visibility().is_none()) - .filter_map(|it| it.use_tree()) - .map(|u| walk_use_tree_for_best_action(&mut storage, None, u, target)) - .fold(None, |best, a| match best { - Some(best) => Some(ImportAction::better(best, a)), - None => Some(a), - }); - - match best_action { - Some(action) => action, - None => { - // We have no action and no UseItem was found in container so we find - // another item and we use it as anchor. - // If there are no items above, we choose the target path itself as anchor. - // todo: we should include even whitespace blocks as anchor candidates - let anchor = container.children().next().or_else(|| Some(anchor)); - - let add_after_anchor = anchor - .clone() - .and_then(ast::Attr::cast) - .map(|attr| attr.kind() == ast::AttrKind::Inner) - .unwrap_or(false); - ImportAction::add_new_use(anchor, add_after_anchor) - } - } -} - -fn make_assist(action: &ImportAction, target: &[SmolStr], edit: &mut TextEditBuilder) { - match action { - ImportAction::AddNewUse { anchor, add_after_anchor } => { - make_assist_add_new_use(anchor, *add_after_anchor, target, edit) - } - ImportAction::AddInTreeList { common_segments, tree_list, add_self } => { - // We know that the fist n segments already exists in the use statement we want - // to modify, so we want to add only the last target.len() - n segments. - let segments_to_add = target.split_at(*common_segments).1; - make_assist_add_in_tree_list(tree_list, segments_to_add, *add_self, edit) - } - ImportAction::AddNestedImport { - common_segments, - path_to_split, - first_segment_to_split, - add_self, - } => { - let segments_to_add = target.split_at(*common_segments).1; - make_assist_add_nested_import( - path_to_split, - first_segment_to_split, - segments_to_add, - *add_self, - edit, - ) - } - _ => {} - } -} - -fn make_assist_add_new_use( - anchor: &Option, - after: bool, - target: &[SmolStr], - edit: &mut TextEditBuilder, -) { - if let Some(anchor) = anchor { - let indent = leading_indent(anchor); - let mut buf = String::new(); - if after { - buf.push_str("\n"); - if let Some(spaces) = &indent { - buf.push_str(spaces); - } - } - buf.push_str("use "); - fmt_segments_raw(target, &mut buf); - buf.push_str(";"); - if !after { - buf.push_str("\n\n"); - if let Some(spaces) = &indent { - buf.push_str(&spaces); - } - } - let position = if after { anchor.text_range().end() } else { anchor.text_range().start() }; - edit.insert(position, buf); - } -} - -fn make_assist_add_in_tree_list( - tree_list: &ast::UseTreeList, - target: &[SmolStr], - add_self: bool, - edit: &mut TextEditBuilder, -) { - let last = tree_list.use_trees().last(); - if let Some(last) = last { - let mut buf = String::new(); - let comma = last.syntax().siblings(Direction::Next).find(|n| n.kind() == T![,]); - let offset = if let Some(comma) = comma { - comma.text_range().end() - } else { - buf.push_str(","); - last.syntax().text_range().end() - }; - if add_self { - buf.push_str(" self") - } else { - buf.push_str(" "); - } - fmt_segments_raw(target, &mut buf); - edit.insert(offset, buf); - } else { - } -} - -fn make_assist_add_nested_import( - path: &ast::Path, - first_segment_to_split: &Option, - target: &[SmolStr], - add_self: bool, - edit: &mut TextEditBuilder, -) { - let use_tree = path.syntax().ancestors().find_map(ast::UseTree::cast); - if let Some(use_tree) = use_tree { - let (start, add_colon_colon) = if let Some(first_segment_to_split) = first_segment_to_split - { - (first_segment_to_split.syntax().text_range().start(), false) - } else { - (use_tree.syntax().text_range().end(), true) - }; - let end = use_tree.syntax().text_range().end(); - - let mut buf = String::new(); - if add_colon_colon { - buf.push_str("::"); - } - buf.push_str("{"); - if add_self { - buf.push_str("self, "); - } - fmt_segments_raw(target, &mut buf); - if !target.is_empty() { - buf.push_str(", "); - } - edit.insert(start, buf); - edit.insert(end, "}".to_string()); - } -} - -/// If the node is on the beginning of the line, calculate indent. -fn leading_indent(node: &SyntaxNode) -> Option { - for token in prev_tokens(node.first_token()?) { - if let Some(ws) = ast::Whitespace::cast(token.clone()) { - let ws_text = ws.text(); - if let Some(pos) = ws_text.rfind('\n') { - return Some(ws_text[pos + 1..].into()); - } - } - if token.text().contains('\n') { - break; - } - } - return None; - fn prev_tokens(token: SyntaxToken) -> impl Iterator { - successors(token.prev_token(), |token| token.prev_token()) - } -} -- cgit v1.2.3