crates/ide_completion/src/completions/postfix.rs

   1 //! Postfix completions, like `Ok(10).ifl$0` => `if let Ok() = Ok(10) { $0 }`.
   2
   3 mod format_like;
   4
   5 use ide_db::{
   6     helpers::{insert_use::ImportScope, FamousDefs, SnippetCap},
   7     ty_filter::TryEnum,
   8 };
   9 use syntax::{
  10     ast::{self, AstNode, AstToken},
  11     SyntaxKind::{EXPR_STMT, STMT_LIST},
  12     TextRange, TextSize,
  13 };
  14 use text_edit::TextEdit;
  15
  16 use crate::{
  17     completions::postfix::format_like::add_format_like_completions,
  18     context::CompletionContext,
  19     item::{Builder, CompletionKind},
  20     patterns::ImmediateLocation,
  21     CompletionItem, CompletionItemKind, CompletionRelevance, Completions,
  22 };
  23
  24 pub(crate) fn complete_postfix(acc: &mut Completions, ctx: &CompletionContext) {
  25     if !ctx.config.enable_postfix_completions {
  26         return;
  27     }
  28
  29     let (dot_receiver, receiver_is_ambiguous_float_literal) = match &ctx.completion_location {
  30         Some(ImmediateLocation::MethodCall { receiver: Some(it), .. }) => (it, false),
  31         Some(ImmediateLocation::FieldAccess {
  32             receiver: Some(it),
  33             receiver_is_ambiguous_float_literal,
  34         }) => (it, *receiver_is_ambiguous_float_literal),
  35         _ => return,
  36     };
  37
  38     let receiver_text = get_receiver_text(dot_receiver, receiver_is_ambiguous_float_literal);
  39
  40     let receiver_ty = match ctx.sema.type_of_expr(dot_receiver) {
  41         Some(it) => it.original,
  42         None => return,
  43     };
  44
  45     // Suggest .await syntax for types that implement Future trait
  46     if receiver_ty.impls_future(ctx.db) {
  47         let mut item = CompletionItem::new(CompletionKind::Keyword, ctx.source_range(), "await");
  48         item.kind(CompletionItemKind::Keyword).detail("expr.await");
  49         item.add_to(acc);
  50     }
  51
  52     let cap = match ctx.config.snippet_cap {
  53         Some(it) => it,
  54         None => return,
  55     };
  56
  57     let postfix_snippet = build_postfix_snippet_builder(ctx, cap, &dot_receiver);
  58
  59     if !ctx.config.postfix_snippets.is_empty() {
  60         add_custom_postfix_completions(acc, ctx, &postfix_snippet, &receiver_text);
  61     }
  62
  63     let try_enum = TryEnum::from_ty(&ctx.sema, &receiver_ty.strip_references());
  64     if let Some(try_enum) = &try_enum {
  65         match try_enum {
  66             TryEnum::Result => {
  67                 postfix_snippet(
  68                     "ifl",
  69                     "if let Ok {}",
  70                     &format!("if let Ok($1) = {} {{\n    $0\n}}", receiver_text),
  71                 )
  72                 .add_to(acc);
  73
  74                 postfix_snippet(
  75                     "while",
  76                     "while let Ok {}",
  77                     &format!("while let Ok($1) = {} {{\n    $0\n}}", receiver_text),
  78                 )
  79                 .add_to(acc);
  80             }
  81             TryEnum::Option => {
  82                 postfix_snippet(
  83                     "ifl",
  84                     "if let Some {}",
  85                     &format!("if let Some($1) = {} {{\n    $0\n}}", receiver_text),
  86                 )
  87                 .add_to(acc);
  88
  89                 postfix_snippet(
  90                     "while",
  91                     "while let Some {}",
  92                     &format!("while let Some($1) = {} {{\n    $0\n}}", receiver_text),
  93                 )
  94                 .add_to(acc);
  95             }
  96         }
  97     } else if receiver_ty.is_bool() || receiver_ty.is_unknown() {
  98         postfix_snippet("if", "if expr {}", &format!("if {} {{\n    $0\n}}", receiver_text))
  99             .add_to(acc);
 100         postfix_snippet(
 101             "while",
 102             "while expr {}",
 103             &format!("while {} {{\n    $0\n}}", receiver_text),
 104         )
 105         .add_to(acc);
 106         postfix_snippet("not", "!expr", &format!("!{}", receiver_text)).add_to(acc);
 107     } else if let Some(trait_) = FamousDefs(&ctx.sema, ctx.krate).core_iter_IntoIterator() {
 108         if receiver_ty.impls_trait(ctx.db, trait_, &[]) {
 109             postfix_snippet(
 110                 "for",
 111                 "for ele in expr {}",
 112                 &format!("for ele in {} {{\n    $0\n}}", receiver_text),
 113             )
 114             .add_to(acc);
 115         }
 116     }
 117
 118     postfix_snippet("ref", "&expr", &format!("&{}", receiver_text)).add_to(acc);
 119     postfix_snippet("refm", "&mut expr", &format!("&mut {}", receiver_text)).add_to(acc);
 120
 121     // The rest of the postfix completions create an expression that moves an argument,
 122     // so it's better to consider references now to avoid breaking the compilation
 123     let dot_receiver = include_references(dot_receiver);
 124     let receiver_text = get_receiver_text(&dot_receiver, receiver_is_ambiguous_float_literal);
 125     let postfix_snippet = build_postfix_snippet_builder(ctx, cap, &dot_receiver);
 126
 127     match try_enum {
 128         Some(try_enum) => match try_enum {
 129             TryEnum::Result => {
 130                 postfix_snippet(
 131                     "match",
 132                     "match expr {}",
 133                     &format!("match {} {{\n    Ok(${{1:_}}) => {{$2}},\n    Err(${{3:_}}) => {{$0}},\n}}", receiver_text),
 134                 )
 135                 .add_to(acc);
 136             }
 137             TryEnum::Option => {
 138                 postfix_snippet(
 139                     "match",
 140                     "match expr {}",
 141                     &format!(
 142                         "match {} {{\n    Some(${{1:_}}) => {{$2}},\n    None => {{$0}},\n}}",
 143                         receiver_text
 144                     ),
 145                 )
 146                 .add_to(acc);
 147             }
 148         },
 149         None => {
 150             postfix_snippet(
 151                 "match",
 152                 "match expr {}",
 153                 &format!("match {} {{\n    ${{1:_}} => {{$0}},\n}}", receiver_text),
 154             )
 155             .add_to(acc);
 156         }
 157     }
 158
 159     postfix_snippet("box", "Box::new(expr)", &format!("Box::new({})", receiver_text)).add_to(acc);
 160     postfix_snippet("ok", "Ok(expr)", &format!("Ok({})", receiver_text)).add_to(acc);
 161     postfix_snippet("err", "Err(expr)", &format!("Err({})", receiver_text)).add_to(acc);
 162     postfix_snippet("some", "Some(expr)", &format!("Some({})", receiver_text)).add_to(acc);
 163     postfix_snippet("dbg", "dbg!(expr)", &format!("dbg!({})", receiver_text)).add_to(acc);
 164     postfix_snippet("dbgr", "dbg!(&expr)", &format!("dbg!(&{})", receiver_text)).add_to(acc);
 165     postfix_snippet("call", "function(expr)", &format!("${{1}}({})", receiver_text)).add_to(acc);
 166
 167     if let Some(parent) = dot_receiver.syntax().parent().and_then(|p| p.parent()) {
 168         if matches!(parent.kind(), STMT_LIST | EXPR_STMT) {
 169             postfix_snippet("let", "let", &format!("let $0 = {};", receiver_text)).add_to(acc);
 170             postfix_snippet("letm", "let mut", &format!("let mut $0 = {};", receiver_text))
 171                 .add_to(acc);
 172         }
 173     }
 174
 175     if let ast::Expr::Literal(literal) = dot_receiver.clone() {
 176         if let Some(literal_text) = ast::String::cast(literal.token()) {
 177             add_format_like_completions(acc, ctx, &dot_receiver, cap, &literal_text);
 178         }
 179     }
 180 }
 181
 182 fn get_receiver_text(receiver: &ast::Expr, receiver_is_ambiguous_float_literal: bool) -> String {
 183     if receiver_is_ambiguous_float_literal {
 184         let text = receiver.syntax().text();
 185         let without_dot = ..text.len() - TextSize::of('.');
 186         text.slice(without_dot).to_string()
 187     } else {
 188         receiver.to_string()
 189     }
 190 }
 191
 192 fn include_references(initial_element: &ast::Expr) -> ast::Expr {
 193     let mut resulting_element = initial_element.clone();
 194     while let Some(parent_ref_element) =
 195         resulting_element.syntax().parent().and_then(ast::RefExpr::cast)
 196     {
 197         resulting_element = ast::Expr::from(parent_ref_element);
 198     }
 199     resulting_element
 200 }
 201
 202 fn build_postfix_snippet_builder<'a>(
 203     ctx: &'a CompletionContext,
 204     cap: SnippetCap,
 205     receiver: &'a ast::Expr,
 206 ) -> impl Fn(&str, &str, &str) -> Builder + 'a {
 207     let receiver_syntax = receiver.syntax();
 208     let receiver_range = ctx.sema.original_range(receiver_syntax).range;
 209     let delete_range = TextRange::new(receiver_range.start(), ctx.source_range().end());
 210
 211     move |label, detail, snippet| {
 212         let edit = TextEdit::replace(delete_range, snippet.to_string());
 213         let mut item = CompletionItem::new(CompletionKind::Postfix, ctx.source_range(), label);
 214         item.detail(detail).kind(CompletionItemKind::Snippet).snippet_edit(cap, edit);
 215         if ctx.original_token.text() == label {
 216             let relevance =
 217                 CompletionRelevance { exact_postfix_snippet_match: true, ..Default::default() };
 218             item.set_relevance(relevance);
 219         }
 220
 221         item
 222     }
 223 }
 224
 225 fn add_custom_postfix_completions(
 226     acc: &mut Completions,
 227     ctx: &CompletionContext,
 228     postfix_snippet: impl Fn(&str, &str, &str) -> Builder,
 229     receiver_text: &str,
 230 ) -> Option<()> {
 231     let import_scope =
 232         ImportScope::find_insert_use_container_with_macros(&ctx.token.parent()?, &ctx.sema)?;
 233     ctx.config.postfix_snippets.iter().for_each(|snippet| {
 234         let imports = match snippet.imports(ctx, &import_scope) {
 235             Some(imports) => imports,
 236             None => return,
 237         };
 238         let mut builder = postfix_snippet(
 239             &snippet.label,
 240             snippet.description.as_deref().unwrap_or_default(),
 241             &format!("{}", snippet.snippet(&receiver_text)),
 242         );
 243         for import in imports.into_iter() {
 244             builder.add_import(import);
 245         }
 246         builder.add_to(acc);
 247     });
 248     None
 249 }
 250
 251 #[cfg(test)]
 252 mod tests {
 253     use expect_test::{expect, Expect};
 254
 255     use crate::{
 256         tests::{check_edit, check_edit_with_config, filtered_completion_list, TEST_CONFIG},
 257         CompletionConfig, CompletionKind, PostfixSnippet,
 258     };
 259
 260     fn check(ra_fixture: &str, expect: Expect) {
 261         let actual = filtered_completion_list(ra_fixture, CompletionKind::Postfix);
 262         expect.assert_eq(&actual)
 263     }
 264
 265     #[test]
 266     fn postfix_completion_works_for_trivial_path_expression() {
 267         check(
 268             r#"
 269 fn main() {
 270     let bar = true;
 271     bar.$0
 272 }
 273 "#,
 274             expect![[r#"
 275                 sn if    if expr {}
 276                 sn while while expr {}
 277                 sn not   !expr
 278                 sn ref   &expr
 279                 sn refm  &mut expr
 280                 sn match match expr {}
 281                 sn box   Box::new(expr)
 282                 sn ok    Ok(expr)
 283                 sn err   Err(expr)
 284                 sn some  Some(expr)
 285                 sn dbg   dbg!(expr)
 286                 sn dbgr  dbg!(&expr)
 287                 sn call  function(expr)
 288                 sn let   let
 289                 sn letm  let mut
 290             "#]],
 291         );
 292     }
 293
 294     #[test]
 295     fn postfix_completion_works_for_function_calln() {
 296         check(
 297             r#"
 298 fn foo(elt: bool) -> bool {
 299     !elt
 300 }
 301
 302 fn main() {
 303     let bar = true;
 304     foo(bar.$0)
 305 }
 306 "#,
 307             expect![[r#"
 308                 sn if    if expr {}
 309                 sn while while expr {}
 310                 sn not   !expr
 311                 sn ref   &expr
 312                 sn refm  &mut expr
 313                 sn match match expr {}
 314                 sn box   Box::new(expr)
 315                 sn ok    Ok(expr)
 316                 sn err   Err(expr)
 317                 sn some  Some(expr)
 318                 sn dbg   dbg!(expr)
 319                 sn dbgr  dbg!(&expr)
 320                 sn call  function(expr)
 321             "#]],
 322         );
 323     }
 324
 325     #[test]
 326     fn postfix_type_filtering() {
 327         check(
 328             r#"
 329 fn main() {
 330     let bar: u8 = 12;
 331     bar.$0
 332 }
 333 "#,
 334             expect![[r#"
 335                 sn ref   &expr
 336                 sn refm  &mut expr
 337                 sn match match expr {}
 338                 sn box   Box::new(expr)
 339                 sn ok    Ok(expr)
 340                 sn err   Err(expr)
 341                 sn some  Some(expr)
 342                 sn dbg   dbg!(expr)
 343                 sn dbgr  dbg!(&expr)
 344                 sn call  function(expr)
 345                 sn let   let
 346                 sn letm  let mut
 347             "#]],
 348         )
 349     }
 350
 351     #[test]
 352     fn let_middle_block() {
 353         check(
 354             r#"
 355 fn main() {
 356     baz.l$0
 357     res
 358 }
 359 "#,
 360             expect![[r#"
 361                 sn if    if expr {}
 362                 sn while while expr {}
 363                 sn not   !expr
 364                 sn ref   &expr
 365                 sn refm  &mut expr
 366                 sn match match expr {}
 367                 sn box   Box::new(expr)
 368                 sn ok    Ok(expr)
 369                 sn err   Err(expr)
 370                 sn some  Some(expr)
 371                 sn dbg   dbg!(expr)
 372                 sn dbgr  dbg!(&expr)
 373                 sn call  function(expr)
 374                 sn let   let
 375                 sn letm  let mut
 376             "#]],
 377         );
 378     }
 379
 380     #[test]
 381     fn option_iflet() {
 382         check_edit(
 383             "ifl",
 384             r#"
 385 //- minicore: option
 386 fn main() {
 387     let bar = Some(true);
 388     bar.$0
 389 }
 390 "#,
 391             r#"
 392 fn main() {
 393     let bar = Some(true);
 394     if let Some($1) = bar {
 395     $0
 396 }
 397 }
 398 "#,
 399         );
 400     }
 401
 402     #[test]
 403     fn result_match() {
 404         check_edit(
 405             "match",
 406             r#"
 407 //- minicore: result
 408 fn main() {
 409     let bar = Ok(true);
 410     bar.$0
 411 }
 412 "#,
 413             r#"
 414 fn main() {
 415     let bar = Ok(true);
 416     match bar {
 417     Ok(${1:_}) => {$2},
 418     Err(${3:_}) => {$0},
 419 }
 420 }
 421 "#,
 422         );
 423     }
 424
 425     #[test]
 426     fn postfix_completion_works_for_ambiguous_float_literal() {
 427         check_edit("refm", r#"fn main() { 42.$0 }"#, r#"fn main() { &mut 42 }"#)
 428     }
 429
 430     #[test]
 431     fn works_in_simple_macro() {
 432         check_edit(
 433             "dbg",
 434             r#"
 435 macro_rules! m { ($e:expr) => { $e } }
 436 fn main() {
 437     let bar: u8 = 12;
 438     m!(bar.d$0)
 439 }
 440 "#,
 441             r#"
 442 macro_rules! m { ($e:expr) => { $e } }
 443 fn main() {
 444     let bar: u8 = 12;
 445     m!(dbg!(bar))
 446 }
 447 "#,
 448         );
 449     }
 450
 451     #[test]
 452     fn postfix_completion_for_references() {
 453         check_edit("dbg", r#"fn main() { &&42.$0 }"#, r#"fn main() { dbg!(&&42) }"#);
 454         check_edit("refm", r#"fn main() { &&42.$0 }"#, r#"fn main() { &&&mut 42 }"#);
 455         check_edit(
 456             "ifl",
 457             r#"
 458 //- minicore: option
 459 fn main() {
 460     let bar = &Some(true);
 461     bar.$0
 462 }
 463 "#,
 464             r#"
 465 fn main() {
 466     let bar = &Some(true);
 467     if let Some($1) = bar {
 468     $0
 469 }
 470 }
 471 "#,
 472         )
 473     }
 474
 475     #[test]
 476     fn custom_postfix_completion() {
 477         check_edit_with_config(
 478             CompletionConfig {
 479                 postfix_snippets: vec![PostfixSnippet::new(
 480                     "break".into(),
 481                     &["ControlFlow::Break($receiver)".into()],
 482                     &[],
 483                     &["core::ops::ControlFlow".into()],
 484                     crate::PostfixSnippetScope::Expr,
 485                 )
 486                 .unwrap()],
 487                 ..TEST_CONFIG
 488             },
 489             "break",
 490             r#"
 491 //- minicore: try
 492 fn main() { 42.$0 }
 493 "#,
 494             r#"
 495 use core::ops::ControlFlow;
 496
 497 fn main() { ControlFlow::Break(42) }
 498 "#,
 499         );
 500     }
 501
 502     #[test]
 503     fn postfix_completion_for_format_like_strings() {
 504         check_edit(
 505             "format",
 506             r#"fn main() { "{some_var:?}".$0 }"#,
 507             r#"fn main() { format!("{:?}", some_var) }"#,
 508         );
 509         check_edit(
 510             "panic",
 511             r#"fn main() { "Panic with {a}".$0 }"#,
 512             r#"fn main() { panic!("Panic with {}", a) }"#,
 513         );
 514         check_edit(
 515             "println",
 516             r#"fn main() { "{ 2+2 } { SomeStruct { val: 1, other: 32 } :?}".$0 }"#,
 517             r#"fn main() { println!("{} {:?}", 2+2, SomeStruct { val: 1, other: 32 }) }"#,
 518         );
 519         check_edit(
 520             "loge",
 521             r#"fn main() { "{2+2}".$0 }"#,
 522             r#"fn main() { log::error!("{}", 2+2) }"#,
 523         );
 524         check_edit(
 525             "logt",
 526             r#"fn main() { "{2+2}".$0 }"#,
 527             r#"fn main() { log::trace!("{}", 2+2) }"#,
 528         );
 529         check_edit(
 530             "logd",
 531             r#"fn main() { "{2+2}".$0 }"#,
 532             r#"fn main() { log::debug!("{}", 2+2) }"#,
 533         );
 534         check_edit("logi", r#"fn main() { "{2+2}".$0 }"#, r#"fn main() { log::info!("{}", 2+2) }"#);
 535         check_edit("logw", r#"fn main() { "{2+2}".$0 }"#, r#"fn main() { log::warn!("{}", 2+2) }"#);
 536         check_edit(
 537             "loge",
 538             r#"fn main() { "{2+2}".$0 }"#,
 539             r#"fn main() { log::error!("{}", 2+2) }"#,
 540         );
 541     }
 542 }