diff --git a/crates/ide-assists/src/handlers/remove_unused_imports.rs b/crates/ide-assists/src/handlers/remove_unused_imports.rs new file mode 100644 index 0000000000..dd4839351f --- /dev/null +++ b/crates/ide-assists/src/handlers/remove_unused_imports.rs @@ -0,0 +1,739 @@ +use std::collections::{hash_map::Entry, HashMap}; + +use hir::{InFile, Module, ModuleSource}; +use ide_db::{ + base_db::FileRange, + defs::Definition, + search::{FileReference, ReferenceCategory, SearchScope}, + RootDatabase, +}; +use syntax::{ast, AstNode}; +use text_edit::TextRange; + +use crate::{AssistContext, AssistId, AssistKind, Assists}; + +// Assist: remove_unused_imports +// +// Removes any use statements in the current selection that are unused. +// +// ``` +// struct X(); +// mod foo { +// use super::X$0; +// } +// ``` +// -> +// ``` +// struct X(); +// mod foo { +// } +// ``` +pub(crate) fn remove_unused_imports(acc: &mut Assists, ctx: &AssistContext<'_>) -> Option<()> { + // First, grab the uses that intersect with the current selection. + let selected_el = match ctx.covering_element() { + syntax::NodeOrToken::Node(n) => n, + syntax::NodeOrToken::Token(t) => t.parent()?, + }; + + // This applies to all uses that are selected, or are ancestors of our selection. + let uses_up = selected_el.ancestors().skip(1).filter_map(ast::Use::cast); + let uses_down = selected_el + .descendants() + .filter(|x| x.text_range().intersect(ctx.selection_trimmed()).is_some()) + .filter_map(ast::Use::cast); + let uses = uses_up.chain(uses_down).collect::>(); + + // Maps use nodes to the scope that we should search through to find + let mut search_scopes = HashMap::>::new(); + + // iterator over all unused use trees + let mut unused = uses + .into_iter() + .flat_map(|u| u.syntax().descendants().filter_map(ast::UseTree::cast)) + .filter(|u| u.use_tree_list().is_none()) + .filter_map(|u| { + // Find any uses trees that are unused + + let use_module = ctx.sema.scope(&u.syntax()).map(|s| s.module())?; + let scope = match search_scopes.entry(use_module) { + Entry::Occupied(o) => o.into_mut(), + Entry::Vacant(v) => v.insert(module_search_scope(ctx.db(), use_module)), + }; + + // Gets the path associated with this use tree. If there isn't one, then ignore this use tree. + let path = if let Some(path) = u.path() { + path + } else if u.star_token().is_some() { + // This case maps to the situation where the * token is braced. + // In this case, the parent use tree's path is the one we should use to resolve the glob. + match u.syntax().ancestors().skip(1).find_map(ast::UseTree::cast) { + Some(parent_u) if parent_u.path().is_some() => parent_u.path().unwrap(), + _ => return None, + } + } else { + return None; + }; + + // Get the actual definition associated with this use item. + let res = match ctx.sema.resolve_path(&path) { + Some(x) => x, + None => { + return None; + } + }; + + let def = match res { + hir::PathResolution::Def(d) => Definition::from(d), + _ => return None, + }; + + if u.star_token().is_some() { + // Check if any of the children of this module are used + let def_mod = match def { + Definition::Module(module) => module, + _ => return None, + }; + + if !def_mod + .scope(ctx.db(), Some(use_module)) + .iter() + .filter_map(|(_, x)| match x { + hir::ScopeDef::ModuleDef(d) => Some(Definition::from(*d)), + _ => None, + }) + .any(|d| used_once_in_scope(ctx, d, scope)) + { + return Some(u); + } + } else if let Definition::Trait(ref t) = def { + // If the trait or any item is used. + if !std::iter::once(def) + .chain(t.items(ctx.db()).into_iter().map(Definition::from)) + .any(|d| used_once_in_scope(ctx, d, scope)) + { + return Some(u); + } + } else { + if !used_once_in_scope(ctx, def, &scope) { + return Some(u); + } + } + + None + }) + .peekable(); + + // Peek so we terminate early if an unused use is found. Only do the rest of the work if the user selects the assist. + if unused.peek().is_some() { + acc.add( + AssistId("remove_unused_imports", AssistKind::QuickFix), + "Remove all the unused imports", + selected_el.text_range(), + |builder| { + let unused: Vec = unused.map(|x| builder.make_mut(x)).collect(); + for node in unused { + node.remove_recursive(); + } + }, + ) + } else { + None + } +} + +fn used_once_in_scope(ctx: &AssistContext<'_>, def: Definition, scopes: &Vec) -> bool { + let mut found = false; + + for scope in scopes { + let mut search_non_import = |_, r: FileReference| { + // The import itself is a use; we must skip that. + if r.category != Some(ReferenceCategory::Import) { + found = true; + true + } else { + false + } + }; + def.usages(&ctx.sema).in_scope(scope).search(&mut search_non_import); + if found { + break; + } + } + + found +} + +/// Build a search scope spanning the given module but none of its submodules. +fn module_search_scope(db: &RootDatabase, module: hir::Module) -> Vec { + let (file_id, range) = { + let InFile { file_id, value } = module.definition_source(db); + if let Some((file_id, call_source)) = file_id.original_call_node(db) { + (file_id, Some(call_source.text_range())) + } else { + ( + file_id.original_file(db), + match value { + ModuleSource::SourceFile(_) => None, + ModuleSource::Module(it) => Some(it.syntax().text_range()), + ModuleSource::BlockExpr(it) => Some(it.syntax().text_range()), + }, + ) + } + }; + + fn split_at_subrange(first: TextRange, second: TextRange) -> (TextRange, Option) { + let intersect = first.intersect(second); + if let Some(intersect) = intersect { + let start_range = TextRange::new(first.start(), intersect.start()); + + if intersect.end() < first.end() { + (start_range, Some(TextRange::new(intersect.end(), first.end()))) + } else { + (start_range, None) + } + } else { + (first, None) + } + } + + let mut scopes = Vec::new(); + if let Some(range) = range { + let mut ranges = vec![range]; + + for child in module.children(db) { + let rng = match child.definition_source(db).value { + ModuleSource::SourceFile(_) => continue, + ModuleSource::Module(it) => it.syntax().text_range(), + ModuleSource::BlockExpr(_) => continue, + }; + let mut new_ranges = Vec::new(); + for old_range in ranges.iter_mut() { + let split = split_at_subrange(old_range.clone(), rng); + *old_range = split.0; + new_ranges.extend(split.1); + } + + ranges.append(&mut new_ranges); + } + + for range in ranges { + scopes.push(SearchScope::file_range(FileRange { file_id, range })); + } + } else { + scopes.push(SearchScope::single_file(file_id)); + } + + scopes +} + +#[cfg(test)] +mod tests { + use crate::tests::{check_assist, check_assist_not_applicable}; + + use super::*; + + #[test] + fn remove_unused() { + check_assist( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + $0use super::X; + use super::Y;$0 +} +"#, + r#" +struct X(); +struct Y(); +mod z { +} +"#, + ); + } + + #[test] + fn remove_unused_is_precise() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod z { +$0use super::X;$0 + +fn w() { + struct X(); + let x = X(); +} +} +"#, + r#" +struct X(); +mod z { + +fn w() { + struct X(); + let x = X(); +} +} +"#, + ); + } + + #[test] + fn trait_name_use_is_use() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +trait Y { + fn f(); +} + +impl Y for X { + fn f() {} +} +mod z { +$0use super::X; +use super::Y;$0 + +fn w() { + X::f(); +} +} +"#, + ); + } + + #[test] + fn trait_item_use_is_use() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +trait Y { + fn f(self); +} + +impl Y for X { + fn f(self) {} +} +mod z { +$0use super::X; +use super::Y;$0 + +fn w() { + let x = X(); + x.f(); +} +} +"#, + ); + } + + #[test] + fn ranamed_trait_item_use_is_use() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +trait Y { + fn f(self); +} + +impl Y for X { + fn f(self) {} +} +mod z { +$0use super::X; +use super::Y as Z;$0 + +fn w() { + let x = X(); + x.f(); +} +} +"#, + ); + } + + #[test] + fn ranamed_underscore_trait_item_use_is_use() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +trait Y { + fn f(self); +} + +impl Y for X { + fn f(self) {} +} +mod z { +$0use super::X; +use super::Y as _;$0 + +fn w() { + let x = X(); + x.f(); +} +} +"#, + ); + } + + #[test] + fn dont_remove_used() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { +$0use super::X; +use super::Y;$0 + +fn w() { + let x = X(); + let y = Y(); +} +} +"#, + ); + } + + #[test] + fn remove_unused_in_braces() { + check_assist( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + $0use super::{X, Y};$0 + + fn w() { + let x = X(); + } +} +"#, + r#" +struct X(); +struct Y(); +mod z { + use super::{X}; + + fn w() { + let x = X(); + } +} +"#, + ); + } + + #[test] + fn remove_unused_under_cursor() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod z { + use super::X$0; +} +"#, + r#" +struct X(); +mod z { +} +"#, + ); + } + + #[test] + fn remove_multi_use_block() { + check_assist( + remove_unused_imports, + r#" +struct X(); +$0mod y { + use super::X; +} +mod z { + use super::X; +}$0 +"#, + r#" +struct X(); +mod y { +} +mod z { +} +"#, + ); + } + + #[test] + fn remove_nested() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod y { + struct Y(); + mod z { + use crate::{X, y::Y}$0; + fn f() { + let x = X(); + } + } +} +"#, + r#" +struct X(); +mod y { + struct Y(); + mod z { + use crate::{X}; + fn f() { + let x = X(); + } + } +} +"#, + ); + } + + #[test] + fn remove_nested_first_item() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod y { + struct Y(); + mod z { + use crate::{X, y::Y}$0; + fn f() { + let y = Y(); + } + } +} +"#, + r#" +struct X(); +mod y { + struct Y(); + mod z { + use crate::{y::Y}; + fn f() { + let y = Y(); + } + } +} +"#, + ); + } + + #[test] + fn remove_nested_all_unused() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod y { + struct Y(); + mod z { + use crate::{X, y::Y}$0; + } +} +"#, + r#" +struct X(); +mod y { + struct Y(); + mod z { + } +} +"#, + ); + } + + #[test] + fn remove_unused_glob() { + check_assist( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + use super::*$0; +} +"#, + r#" +struct X(); +struct Y(); +mod z { +} +"#, + ); + } + + #[test] + fn remove_unused_braced_glob() { + check_assist( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + use super::{*}$0; +} +"#, + r#" +struct X(); +struct Y(); +mod z { +} +"#, + ); + } + + #[test] + fn dont_remove_used_glob() { + check_assist_not_applicable( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + use super::*$0; + + fn f() { + let x = X(); + } +} +"#, + ); + } + + #[test] + fn only_remove_from_selection() { + check_assist( + remove_unused_imports, + r#" +struct X(); +struct Y(); +mod z { + $0use super::X;$0 + use super::Y; +} +mod w { + use super::Y; +} +"#, + r#" +struct X(); +struct Y(); +mod z { + use super::Y; +} +mod w { + use super::Y; +} +"#, + ); + } + + #[test] + fn test_several_files() { + check_assist( + remove_unused_imports, + r#" +//- /foo.rs +pub struct X(); +pub struct Y(); + +//- /main.rs +$0use foo::X; +use foo::Y; +$0 +mod foo; +mod z { + use crate::foo::X; +} +"#, + r#" + +mod foo; +mod z { + use crate::foo::X; +} +"#, + ); + } + + #[test] + fn use_in_submodule_doesnt_count() { + check_assist( + remove_unused_imports, + r#" +struct X(); +mod z { + use super::X$0; + + mod w { + use crate::X; + + fn f() { + let x = X(); + } + } +} +"#, + r#" +struct X(); +mod z { + + mod w { + use crate::X; + + fn f() { + let x = X(); + } + } +} +"#, + ); + } + + #[test] + fn use_in_submodule_file_doesnt_count() { + check_assist( + remove_unused_imports, + r#" +//- /z/foo.rs +use crate::X; +fn f() { + let x = X(); +} + +//- /main.rs +pub struct X(); + +mod z { + use crate::X$0; + mod foo; +} +"#, + r#" +pub struct X(); + +mod z { + mod foo; +} +"#, + ); + } +} diff --git a/crates/ide-assists/src/lib.rs b/crates/ide-assists/src/lib.rs index a82f1f9dd8..2ebb5ef9b1 100644 --- a/crates/ide-assists/src/lib.rs +++ b/crates/ide-assists/src/lib.rs @@ -184,6 +184,7 @@ mod handlers { mod raw_string; mod remove_dbg; mod remove_mut; + mod remove_unused_imports; mod remove_unused_param; mod remove_parentheses; mod reorder_fields; @@ -294,6 +295,7 @@ mod handlers { raw_string::make_usual_string, raw_string::remove_hash, remove_mut::remove_mut, + remove_unused_imports::remove_unused_imports, remove_unused_param::remove_unused_param, remove_parentheses::remove_parentheses, reorder_fields::reorder_fields, diff --git a/crates/ide-assists/src/tests/generated.rs b/crates/ide-assists/src/tests/generated.rs index 4d47a199b7..ec3822c3d1 100644 --- a/crates/ide-assists/src/tests/generated.rs +++ b/crates/ide-assists/src/tests/generated.rs @@ -2233,6 +2233,24 @@ fn main() { ) } +#[test] +fn doctest_remove_unused_imports() { + check_doc_test( + "remove_unused_imports", + r#####" +struct X(); +mod foo { + use super::X$0; +} +"#####, + r#####" +struct X(); +mod foo { +} +"#####, + ) +} + #[test] fn doctest_remove_unused_param() { check_doc_test( diff --git a/crates/syntax/src/ast/edit_in_place.rs b/crates/syntax/src/ast/edit_in_place.rs index 5919609d91..96b438f1a0 100644 --- a/crates/syntax/src/ast/edit_in_place.rs +++ b/crates/syntax/src/ast/edit_in_place.rs @@ -358,6 +358,26 @@ impl Removable for ast::UseTree { } impl ast::UseTree { + /// Deletes the usetree node represented by the input. Recursively removes parents, including use nodes that become empty. + pub fn remove_recursive(self) { + let parent = self.syntax().parent(); + + self.remove(); + + if let Some(u) = parent.clone().and_then(ast::Use::cast) { + if u.use_tree().is_none() { + u.remove(); + } + } else if let Some(u) = parent.and_then(ast::UseTreeList::cast) { + if u.use_trees().next().is_none() { + let parent = u.syntax().parent().and_then(ast::UseTree::cast); + if let Some(u) = parent { + u.remove_recursive(); + } + } + } + } + pub fn get_or_create_use_tree_list(&self) -> ast::UseTreeList { match self.use_tree_list() { Some(it) => it, @@ -465,6 +485,22 @@ impl Removable for ast::Use { } } } + let prev_ws = self + .syntax() + .prev_sibling_or_token() + .and_then(|it| it.into_token()) + .and_then(ast::Whitespace::cast); + if let Some(prev_ws) = prev_ws { + let ws_text = prev_ws.syntax().text(); + let prev_newline = ws_text.rfind('\n').map(|x| x + 1).unwrap_or(0); + let rest = &ws_text[0..prev_newline]; + if rest.is_empty() { + ted::remove(prev_ws.syntax()); + } else { + ted::replace(prev_ws.syntax(), make::tokens::whitespace(rest)); + } + } + ted::remove(self.syntax()); } }