crates/ide_assists/src/handlers/unmerge_use.rs

   1 use syntax::{
   2     ast::{self, VisibilityOwner},
   3     ted::{self, Position},
   4     AstNode, SyntaxKind,
   5 };
   6
   7 use crate::{
   8     assist_context::{AssistContext, Assists},
   9     AssistId, AssistKind,
  10 };
  11
  12 // Assist: unmerge_use
  13 //
  14 // Extracts single use item from use list.
  15 //
  16 // ```
  17 // use std::fmt::{Debug, Display$0};
  18 // ```
  19 // ->
  20 // ```
  21 // use std::fmt::{Debug};
  22 // use std::fmt::Display;
  23 // ```
  24 pub(crate) fn unmerge_use(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
  25     let tree: ast::UseTree = ctx.find_node_at_offset::<ast::UseTree>()?.clone_for_update();
  26
  27     let tree_list = tree.syntax().parent().and_then(ast::UseTreeList::cast)?;
  28     if tree_list.use_trees().count() < 2 {
  29         cov_mark::hit!(skip_single_use_item);
  30         return None;
  31     }
  32
  33     let use_: ast::Use = tree_list.syntax().ancestors().find_map(ast::Use::cast)?;
  34     let path = resolve_full_path(&tree)?;
  35
  36     let old_parent_range = use_.syntax().parent()?.text_range();
  37     let new_parent = use_.syntax().parent()?;
  38
  39     let target = tree.syntax().text_range();
  40     acc.add(
  41         AssistId("unmerge_use", AssistKind::RefactorRewrite),
  42         "Unmerge use",
  43         target,
  44         |builder| {
  45             let new_use = ast::make::use_(
  46                 use_.visibility(),
  47                 ast::make::use_tree(
  48                     path,
  49                     tree.use_tree_list(),
  50                     tree.rename(),
  51                     tree.star_token().is_some(),
  52                 ),
  53             )
  54             .clone_for_update();
  55
  56             tree.remove();
  57             ted::insert(Position::after(use_.syntax()), new_use.syntax());
  58
  59             builder.replace(old_parent_range, new_parent.to_string());
  60         },
  61     )
  62 }
  63
  64 fn resolve_full_path(tree: &ast::UseTree) -> Option<ast::Path> {
  65     let mut paths = tree
  66         .syntax()
  67         .ancestors()
  68         .take_while(|n| n.kind() != SyntaxKind::USE_KW)
  69         .filter_map(ast::UseTree::cast)
  70         .filter_map(|t| t.path());
  71
  72     let mut final_path = paths.next()?;
  73     for path in paths {
  74         final_path = ast::make::path_concat(path, final_path)
  75     }
  76     Some(final_path)
  77 }
  78
  79 #[cfg(test)]
  80 mod tests {
  81     use crate::tests::{check_assist, check_assist_not_applicable};
  82
  83     use super::*;
  84
  85     #[test]
  86     fn skip_single_use_item() {
  87         cov_mark::check!(skip_single_use_item);
  88         check_assist_not_applicable(
  89             unmerge_use,
  90             r"
  91 use std::fmt::Debug$0;
  92 ",
  93         );
  94         check_assist_not_applicable(
  95             unmerge_use,
  96             r"
  97 use std::fmt::{Debug$0};
  98 ",
  99         );
 100         check_assist_not_applicable(
 101             unmerge_use,
 102             r"
 103 use std::fmt::Debug as Dbg$0;
 104 ",
 105         );
 106     }
 107
 108     #[test]
 109     fn skip_single_glob_import() {
 110         check_assist_not_applicable(
 111             unmerge_use,
 112             r"
 113 use std::fmt::*$0;
 114 ",
 115         );
 116     }
 117
 118     #[test]
 119     fn unmerge_use_item() {
 120         check_assist(
 121             unmerge_use,
 122             r"
 123 use std::fmt::{Debug, Display$0};
 124 ",
 125             r"
 126 use std::fmt::{Debug};
 127 use std::fmt::Display;
 128 ",
 129         );
 130
 131         check_assist(
 132             unmerge_use,
 133             r"
 134 use std::fmt::{Debug, format$0, Display};
 135 ",
 136             r"
 137 use std::fmt::{Debug, Display};
 138 use std::fmt::format;
 139 ",
 140         );
 141     }
 142
 143     #[test]
 144     fn unmerge_glob_import() {
 145         check_assist(
 146             unmerge_use,
 147             r"
 148 use std::fmt::{*$0, Display};
 149 ",
 150             r"
 151 use std::fmt::{Display};
 152 use std::fmt::*;
 153 ",
 154         );
 155     }
 156
 157     #[test]
 158     fn unmerge_renamed_use_item() {
 159         check_assist(
 160             unmerge_use,
 161             r"
 162 use std::fmt::{Debug, Display as Disp$0};
 163 ",
 164             r"
 165 use std::fmt::{Debug};
 166 use std::fmt::Display as Disp;
 167 ",
 168         );
 169     }
 170
 171     #[test]
 172     fn unmerge_indented_use_item() {
 173         check_assist(
 174             unmerge_use,
 175             r"
 176 mod format {
 177     use std::fmt::{Debug, Display$0 as Disp, format};
 178 }
 179 ",
 180             r"
 181 mod format {
 182     use std::fmt::{Debug, format};
 183     use std::fmt::Display as Disp;
 184 }
 185 ",
 186         );
 187     }
 188
 189     #[test]
 190     fn unmerge_nested_use_item() {
 191         check_assist(
 192             unmerge_use,
 193             r"
 194 use foo::bar::{baz::{qux$0, foobar}, barbaz};
 195 ",
 196             r"
 197 use foo::bar::{baz::{foobar}, barbaz};
 198 use foo::bar::baz::qux;
 199 ",
 200         );
 201         check_assist(
 202             unmerge_use,
 203             r"
 204 use foo::bar::{baz$0::{qux, foobar}, barbaz};
 205 ",
 206             r"
 207 use foo::bar::{barbaz};
 208 use foo::bar::baz::{qux, foobar};
 209 ",
 210         );
 211     }
 212
 213     #[test]
 214     fn unmerge_use_item_with_visibility() {
 215         check_assist(
 216             unmerge_use,
 217             r"
 218 pub use std::fmt::{Debug, Display$0};
 219 ",
 220             r"
 221 pub use std::fmt::{Debug};
 222 pub use std::fmt::Display;
 223 ",
 224         );
 225     }
 226 }