crates/ide_assists/src/handlers/split_import.rs

   1 use syntax::{ast, AstNode, T};
   2
   3 use crate::{AssistContext, AssistId, AssistKind, Assists};
   4
   5 // Assist: split_import
   6 //
   7 // Wraps the tail of import into braces.
   8 //
   9 // ```
  10 // use std::$0collections::HashMap;
  11 // ```
  12 // ->
  13 // ```
  14 // use std::{collections::HashMap};
  15 // ```
  16 pub(crate) fn split_import(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
  17     let colon_colon = ctx.find_token_syntax_at_offset(T![::])?;
  18     let path = ast::Path::cast(colon_colon.parent()?)?.qualifier()?;
  19
  20     let use_tree = path.top_path().syntax().ancestors().find_map(ast::UseTree::cast)?;
  21
  22     let has_errors = use_tree
  23         .syntax()
  24         .descendants_with_tokens()
  25         .any(|it| it.kind() == syntax::SyntaxKind::ERROR);
  26     let last_segment = use_tree.path().and_then(|it| it.segment());
  27     if has_errors || last_segment.is_none() {
  28         return None;
  29     }
  30
  31     let target = colon_colon.text_range();
  32     acc.add(AssistId("split_import", AssistKind::RefactorRewrite), "Split import", target, |edit| {
  33         let use_tree = edit.make_mut(use_tree.clone());
  34         let path = edit.make_mut(path);
  35         use_tree.split_prefix(&path);
  36     })
  37 }
  38
  39 #[cfg(test)]
  40 mod tests {
  41     use crate::tests::{check_assist, check_assist_not_applicable, check_assist_target};
  42
  43     use super::*;
  44
  45     #[test]
  46     fn test_split_import() {
  47         check_assist(
  48             split_import,
  49             "use crate::$0db::RootDatabase;",
  50             "use crate::{db::RootDatabase};",
  51         )
  52     }
  53
  54     #[test]
  55     fn split_import_works_with_trees() {
  56         check_assist(
  57             split_import,
  58             "use crate:$0:db::{RootDatabase, FileSymbol}",
  59             "use crate::{db::{RootDatabase, FileSymbol}}",
  60         )
  61     }
  62
  63     #[test]
  64     fn split_import_target() {
  65         check_assist_target(split_import, "use crate::$0db::{RootDatabase, FileSymbol}", "::");
  66     }
  67
  68     #[test]
  69     fn issue4044() {
  70         check_assist_not_applicable(split_import, "use crate::$0:::self;")
  71     }
  72
  73     #[test]
  74     fn test_empty_use() {
  75         check_assist_not_applicable(
  76             split_import,
  77             r"
  78 use std::$0
  79 fn main() {}",
  80         );
  81     }
  82 }