crates/assists/src/lib.rs

   1 //! `assists` crate provides a bunch of code assists, also known as code
   2 //! actions (in LSP) or intentions (in IntelliJ).
   3 //!
   4 //! An assist is a micro-refactoring, which is automatically activated in
   5 //! certain context. For example, if the cursor is over `,`, a "swap `,`" assist
   6 //! becomes available.
   7
   8 #[allow(unused)]
   9 macro_rules! eprintln {
  10     ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
  11 }
  12
  13 mod assist_config;
  14 mod assist_context;
  15 #[cfg(test)]
  16 mod tests;
  17 pub mod utils;
  18 pub mod ast_transform;
  19
  20 use hir::Semantics;
  21 use ide_db::base_db::FileRange;
  22 use ide_db::{label::Label, source_change::SourceChange, RootDatabase};
  23 use syntax::TextRange;
  24
  25 pub(crate) use crate::assist_context::{AssistContext, Assists};
  26
  27 pub use assist_config::AssistConfig;
  28
  29 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
  30 pub enum AssistKind {
  31     None,
  32     QuickFix,
  33     Generate,
  34     Refactor,
  35     RefactorExtract,
  36     RefactorInline,
  37     RefactorRewrite,
  38 }
  39
  40 impl AssistKind {
  41     pub fn contains(self, other: AssistKind) -> bool {
  42         if self == other {
  43             return true;
  44         }
  45
  46         match self {
  47             AssistKind::None | AssistKind::Generate => return true,
  48             AssistKind::Refactor => match other {
  49                 AssistKind::RefactorExtract
  50                 | AssistKind::RefactorInline
  51                 | AssistKind::RefactorRewrite => return true,
  52                 _ => return false,
  53             },
  54             _ => return false,
  55         }
  56     }
  57 }
  58
  59 /// Unique identifier of the assist, should not be shown to the user
  60 /// directly.
  61 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
  62 pub struct AssistId(pub &'static str, pub AssistKind);
  63
  64 #[derive(Clone, Debug)]
  65 pub struct GroupLabel(pub String);
  66
  67 #[derive(Debug, Clone)]
  68 pub struct Assist {
  69     pub id: AssistId,
  70     /// Short description of the assist, as shown in the UI.
  71     pub label: Label,
  72     pub group: Option<GroupLabel>,
  73     /// Target ranges are used to sort assists: the smaller the target range,
  74     /// the more specific assist is, and so it should be sorted first.
  75     pub target: TextRange,
  76     /// Computing source change sometimes is much more costly then computing the
  77     /// other fields. Additionally, the actual change is not required to show
  78     /// the lightbulb UI, it only is needed when the user tries to apply an
  79     /// assist. So, we compute it lazily: the API allow requesting assists with
  80     /// or without source change. We could (and in fact, used to) distinguish
  81     /// between resolved and unresolved assists at the type level, but this is
  82     /// cumbersome, especially if you want to embed an assist into another data
  83     /// structure, such as a diagnostic.
  84     pub source_change: Option<SourceChange>,
  85 }
  86
  87 impl Assist {
  88     /// Return all the assists applicable at the given position.
  89     pub fn get(
  90         db: &RootDatabase,
  91         config: &AssistConfig,
  92         resolve: bool,
  93         range: FileRange,
  94     ) -> Vec<Assist> {
  95         let sema = Semantics::new(db);
  96         let ctx = AssistContext::new(sema, config, range);
  97         let mut acc = Assists::new(&ctx, resolve);
  98         handlers::all().iter().for_each(|handler| {
  99             handler(&mut acc, &ctx);
 100         });
 101         acc.finish()
 102     }
 103 }
 104
 105 mod handlers {
 106     use crate::{AssistContext, Assists};
 107
 108     pub(crate) type Handler = fn(&mut Assists, &AssistContext) -> Option<()>;
 109
 110     mod add_explicit_type;
 111     mod add_missing_impl_members;
 112     mod add_turbo_fish;
 113     mod apply_demorgan;
 114     mod auto_import;
 115     mod change_visibility;
 116     mod convert_integer_literal;
 117     mod early_return;
 118     mod expand_glob_import;
 119     mod extract_struct_from_enum_variant;
 120     mod extract_variable;
 121     mod fill_match_arms;
 122     mod fix_visibility;
 123     mod flip_binexpr;
 124     mod flip_comma;
 125     mod flip_trait_bound;
 126     mod generate_default_from_enum_variant;
 127     mod generate_derive;
 128     mod generate_from_impl_for_enum;
 129     mod generate_function;
 130     mod generate_impl;
 131     mod generate_new;
 132     mod infer_function_return_type;
 133     mod inline_function;
 134     mod inline_local_variable;
 135     mod introduce_named_lifetime;
 136     mod invert_if;
 137     mod merge_imports;
 138     mod merge_match_arms;
 139     mod move_bounds;
 140     mod move_guard;
 141     mod move_module_to_file;
 142     mod pull_assignment_up;
 143     mod qualify_path;
 144     mod raw_string;
 145     mod remove_dbg;
 146     mod remove_mut;
 147     mod remove_unused_param;
 148     mod reorder_fields;
 149     mod reorder_impl;
 150     mod replace_derive_with_manual_impl;
 151     mod replace_if_let_with_match;
 152     mod replace_impl_trait_with_generic;
 153     mod replace_let_with_if_let;
 154     mod replace_qualified_name_with_use;
 155     mod replace_string_with_char;
 156     mod replace_unwrap_with_match;
 157     mod split_import;
 158     mod toggle_ignore;
 159     mod unmerge_use;
 160     mod unwrap_block;
 161     mod wrap_return_type_in_result;
 162
 163     pub(crate) fn all() -> &'static [Handler] {
 164         &[
 165             // These are alphabetic for the foolish consistency
 166             add_explicit_type::add_explicit_type,
 167             add_turbo_fish::add_turbo_fish,
 168             apply_demorgan::apply_demorgan,
 169             auto_import::auto_import,
 170             change_visibility::change_visibility,
 171             convert_integer_literal::convert_integer_literal,
 172             early_return::convert_to_guarded_return,
 173             expand_glob_import::expand_glob_import,
 174             move_module_to_file::move_module_to_file,
 175             extract_struct_from_enum_variant::extract_struct_from_enum_variant,
 176             extract_variable::extract_variable,
 177             fill_match_arms::fill_match_arms,
 178             fix_visibility::fix_visibility,
 179             flip_binexpr::flip_binexpr,
 180             flip_comma::flip_comma,
 181             flip_trait_bound::flip_trait_bound,
 182             generate_default_from_enum_variant::generate_default_from_enum_variant,
 183             generate_derive::generate_derive,
 184             generate_from_impl_for_enum::generate_from_impl_for_enum,
 185             generate_function::generate_function,
 186             generate_impl::generate_impl,
 187             generate_new::generate_new,
 188             infer_function_return_type::infer_function_return_type,
 189             inline_function::inline_function,
 190             inline_local_variable::inline_local_variable,
 191             introduce_named_lifetime::introduce_named_lifetime,
 192             invert_if::invert_if,
 193             merge_imports::merge_imports,
 194             merge_match_arms::merge_match_arms,
 195             move_bounds::move_bounds_to_where_clause,
 196             move_guard::move_arm_cond_to_match_guard,
 197             move_guard::move_guard_to_arm_body,
 198             pull_assignment_up::pull_assignment_up,
 199             qualify_path::qualify_path,
 200             raw_string::add_hash,
 201             raw_string::make_usual_string,
 202             raw_string::remove_hash,
 203             remove_dbg::remove_dbg,
 204             remove_mut::remove_mut,
 205             remove_unused_param::remove_unused_param,
 206             reorder_fields::reorder_fields,
 207             reorder_impl::reorder_impl,
 208             replace_derive_with_manual_impl::replace_derive_with_manual_impl,
 209             replace_if_let_with_match::replace_if_let_with_match,
 210             replace_if_let_with_match::replace_match_with_if_let,
 211             replace_impl_trait_with_generic::replace_impl_trait_with_generic,
 212             replace_let_with_if_let::replace_let_with_if_let,
 213             replace_qualified_name_with_use::replace_qualified_name_with_use,
 214             replace_unwrap_with_match::replace_unwrap_with_match,
 215             split_import::split_import,
 216             toggle_ignore::toggle_ignore,
 217             unmerge_use::unmerge_use,
 218             unwrap_block::unwrap_block,
 219             wrap_return_type_in_result::wrap_return_type_in_result,
 220             // These are manually sorted for better priorities
 221             add_missing_impl_members::add_missing_impl_members,
 222             add_missing_impl_members::add_missing_default_members,
 223             //
 224             replace_string_with_char::replace_string_with_char,
 225             raw_string::make_raw_string,
 226             // Are you sure you want to add new assist here, and not to the
 227             // sorted list above?
 228         ]
 229     }
 230 }