Auto merge of #17073 - roife:better-inline-preview, r=Veykril

Better inline preview for postfix completion

Better inline preview for postfix completion, a proper implementation of c5686c8.

Here editors may filter completion item with the text within `delete_range`, so we need to include the `receiver text` in the `lookup` (aka `FilterText` in LSP spec) for editors to find the completion item. (See rust-lang/rust-analyzer#17036 (comment), Thanks to [pascalkuthe](https://github.com/pascalkuthe))

Author: bors

crates/ide-completion/src/completions/dot.rs

@@ -1035,7 +1035,7 @@ fn main() {
     fn postfix_drop_completion() {
         cov_mark::check!(postfix_drop_completion);
         check_edit(
-            "drop",
+            "x.drop",
             r#"
 //- minicore: drop
 struct Vec<T>(T);

crates/ide-completion/src/completions/postfix.rs

@@ -12,6 +12,7 @@ use ide_db::{
 use stdx::never;
 use syntax::{
     ast::{self, make, AstNode, AstToken},
+    format_smolstr,
     SyntaxKind::{BLOCK_EXPR, EXPR_STMT, FOR_EXPR, IF_EXPR, LOOP_EXPR, STMT_LIST, WHILE_EXPR},
     TextRange, TextSize,
 };
@@ -55,10 +56,11 @@ pub(crate) fn complete_postfix(
         None => return,
     };
 
-    let postfix_snippet = match build_postfix_snippet_builder(ctx, cap, dot_receiver) {
-        Some(it) => it,
-        None => return,
-    };
+    let postfix_snippet =
+        match build_postfix_snippet_builder(ctx, cap, dot_receiver, &receiver_text) {
+            Some(it) => it,
+            None => return,
+        };
 
     if let Some(drop_trait) = ctx.famous_defs().core_ops_Drop() {
         if receiver_ty.impls_trait(ctx.db, drop_trait, &[]) {
@@ -173,10 +175,11 @@ pub(crate) fn complete_postfix(
     let (dot_receiver, node_to_replace_with) = include_references(dot_receiver);
     let receiver_text =
         get_receiver_text(&node_to_replace_with, receiver_is_ambiguous_float_literal);
-    let postfix_snippet = match build_postfix_snippet_builder(ctx, cap, &dot_receiver) {
-        Some(it) => it,
-        None => return,
-    };
+    let postfix_snippet =
+        match build_postfix_snippet_builder(ctx, cap, &dot_receiver, &receiver_text) {
+            Some(it) => it,
+            None => return,
+        };
 
     if !ctx.config.snippets.is_empty() {
         add_custom_postfix_completions(acc, ctx, &postfix_snippet, &receiver_text);
@@ -317,6 +320,7 @@ fn build_postfix_snippet_builder<'ctx>(
     ctx: &'ctx CompletionContext<'_>,
     cap: SnippetCap,
     receiver: &'ctx ast::Expr,
+    receiver_text: &'ctx str,
 ) -> Option<impl Fn(&str, &str, &str) -> Builder + 'ctx> {
     let receiver_range = ctx.sema.original_range_opt(receiver.syntax())?.range;
     if ctx.source_range().end() < receiver_range.start() {
@@ -332,13 +336,16 @@ fn build_postfix_snippet_builder<'ctx>(
     fn build<'ctx>(
         ctx: &'ctx CompletionContext<'_>,
         cap: SnippetCap,
+        receiver_text: &'ctx str,
         delete_range: TextRange,
     ) -> impl Fn(&str, &str, &str) -> Builder + 'ctx {
         move |label, detail, snippet| {
             let edit = TextEdit::replace(delete_range, snippet.to_owned());
-            let mut item =
-                CompletionItem::new(CompletionItemKind::Snippet, ctx.source_range(), label);
+            let mut item = CompletionItem::new(CompletionItemKind::Snippet, delete_range, label);
             item.detail(detail).snippet_edit(cap, edit);
+            // Editors may filter completion item with the text within delete_range, so we need to
+            // include the receiver text in the lookup for editors to find the completion item.
+            item.lookup_by(format_smolstr!("{}.{}", receiver_text, label));
             let postfix_match = if ctx.original_token.text() == label {
                 cov_mark::hit!(postfix_exact_match_is_high_priority);
                 Some(CompletionRelevancePostfixMatch::Exact)
@@ -351,7 +358,7 @@ fn build_postfix_snippet_builder<'ctx>(
             item
         }
     }
-    Some(build(ctx, cap, delete_range))
+    Some(build(ctx, cap, receiver_text, delete_range))
 }
 
 fn add_custom_postfix_completions(
@@ -512,7 +519,7 @@ fn main() {
     #[test]
     fn option_iflet() {
         check_edit(
-            "ifl",
+            "bar.ifl",
             r#"
 //- minicore: option
 fn main() {
@@ -534,7 +541,7 @@ fn main() {
     #[test]
     fn option_letelse() {
         check_edit(
-            "lete",
+            "bar.lete",
             r#"
 //- minicore: option
 fn main() {
@@ -557,7 +564,7 @@ $0
     #[test]
     fn result_match() {
         check_edit(
-            "match",
+            "bar.match",
             r#"
 //- minicore: result
 fn main() {
@@ -579,13 +586,13 @@ fn main() {
 
     #[test]
     fn postfix_completion_works_for_ambiguous_float_literal() {
-        check_edit("refm", r#"fn main() { 42.$0 }"#, r#"fn main() { &mut 42 }"#)
+        check_edit("42.refm", r#"fn main() { 42.$0 }"#, r#"fn main() { &mut 42 }"#)
     }
 
     #[test]
     fn works_in_simple_macro() {
         check_edit(
-            "dbg",
+            "bar.dbg",
             r#"
 macro_rules! m { ($e:expr) => { $e } }
 fn main() {
@@ -605,10 +612,10 @@ fn main() {
 
     #[test]
     fn postfix_completion_for_references() {
-        check_edit("dbg", r#"fn main() { &&42.$0 }"#, r#"fn main() { dbg!(&&42) }"#);
-        check_edit("refm", r#"fn main() { &&42.$0 }"#, r#"fn main() { &&&mut 42 }"#);
+        check_edit("&&42.dbg", r#"fn main() { &&42.$0 }"#, r#"fn main() { dbg!(&&42) }"#);
+        check_edit("42.refm", r#"fn main() { &&42.$0 }"#, r#"fn main() { &&&mut 42 }"#);
         check_edit(
-            "ifl",
+            "bar.ifl",
             r#"
 //- minicore: option
 fn main() {
@@ -629,35 +636,39 @@ fn main() {
 
     #[test]
     fn postfix_completion_for_unsafe() {
-        check_edit("unsafe", r#"fn main() { foo.$0 }"#, r#"fn main() { unsafe { foo } }"#);
-        check_edit("unsafe", r#"fn main() { { foo }.$0 }"#, r#"fn main() { unsafe { foo } }"#);
+        check_edit("foo.unsafe", r#"fn main() { foo.$0 }"#, r#"fn main() { unsafe { foo } }"#);
         check_edit(
-            "unsafe",
+            "{ foo }.unsafe",
+            r#"fn main() { { foo }.$0 }"#,
+            r#"fn main() { unsafe { foo } }"#,
+        );
+        check_edit(
+            "if x { foo }.unsafe",
             r#"fn main() { if x { foo }.$0 }"#,
             r#"fn main() { unsafe { if x { foo } } }"#,
         );
         check_edit(
-            "unsafe",
+            "loop { foo }.unsafe",
             r#"fn main() { loop { foo }.$0 }"#,
             r#"fn main() { unsafe { loop { foo } } }"#,
         );
         check_edit(
-            "unsafe",
+            "if true {}.unsafe",
             r#"fn main() { if true {}.$0 }"#,
             r#"fn main() { unsafe { if true {} } }"#,
         );
         check_edit(
-            "unsafe",
+            "while true {}.unsafe",
             r#"fn main() { while true {}.$0 }"#,
             r#"fn main() { unsafe { while true {} } }"#,
         );
         check_edit(
-            "unsafe",
+            "for i in 0..10 {}.unsafe",
             r#"fn main() { for i in 0..10 {}.$0 }"#,
             r#"fn main() { unsafe { for i in 0..10 {} } }"#,
         );
         check_edit(
-            "unsafe",
+            "if true {1} else {2}.unsafe",
             r#"fn main() { let x = if true {1} else {2}.$0 }"#,
             r#"fn main() { let x = unsafe { if true {1} else {2} } }"#,
         );
@@ -687,7 +698,7 @@ fn main() {
 
         check_edit_with_config(
             config.clone(),
-            "break",
+            "42.break",
             r#"
 //- minicore: try
 fn main() { 42.$0 }
@@ -706,7 +717,7 @@ fn main() { ControlFlow::Break(42) }
         // what users would see. Unescaping happens thereafter.
         check_edit_with_config(
             config.clone(),
-            "break",
+            r#"'\\\\'.break"#,
             r#"
 //- minicore: try
 fn main() { '\\'.$0 }
@@ -720,7 +731,10 @@ fn main() { ControlFlow::Break('\\\\') }
 
         check_edit_with_config(
             config,
-            "break",
+            r#"match true {
+        true => "\${1:placeholder}",
+        false => "\\\$",
+    }.break"#,
             r#"
 //- minicore: try
 fn main() {
@@ -746,39 +760,47 @@ fn main() {
     #[test]
     fn postfix_completion_for_format_like_strings() {
         check_edit(
-            "format",
+            r#""{some_var:?}".format"#,
             r#"fn main() { "{some_var:?}".$0 }"#,
             r#"fn main() { format!("{some_var:?}") }"#,
         );
         check_edit(
-            "panic",
+            r#""Panic with {a}".panic"#,
             r#"fn main() { "Panic with {a}".$0 }"#,
             r#"fn main() { panic!("Panic with {a}") }"#,
         );
         check_edit(
-            "println",
+            r#""{ 2+2 } { SomeStruct { val: 1, other: 32 } :?}".println"#,
             r#"fn main() { "{ 2+2 } { SomeStruct { val: 1, other: 32 } :?}".$0 }"#,
             r#"fn main() { println!("{} {:?}", 2+2, SomeStruct { val: 1, other: 32 }) }"#,
         );
         check_edit(
-            "loge",
+            r#""{2+2}".loge"#,
             r#"fn main() { "{2+2}".$0 }"#,
             r#"fn main() { log::error!("{}", 2+2) }"#,
         );
         check_edit(
-            "logt",
+            r#""{2+2}".logt"#,
             r#"fn main() { "{2+2}".$0 }"#,
             r#"fn main() { log::trace!("{}", 2+2) }"#,
         );
         check_edit(
-            "logd",
+            r#""{2+2}".logd"#,
             r#"fn main() { "{2+2}".$0 }"#,
             r#"fn main() { log::debug!("{}", 2+2) }"#,
         );
-        check_edit("logi", r#"fn main() { "{2+2}".$0 }"#, r#"fn main() { log::info!("{}", 2+2) }"#);
-        check_edit("logw", r#"fn main() { "{2+2}".$0 }"#, r#"fn main() { log::warn!("{}", 2+2) }"#);
         check_edit(
-            "loge",
+            r#""{2+2}".logi"#,
+            r#"fn main() { "{2+2}".$0 }"#,
+            r#"fn main() { log::info!("{}", 2+2) }"#,
+        );
+        check_edit(
+            r#""{2+2}".logw"#,
+            r#"fn main() { "{2+2}".$0 }"#,
+            r#"fn main() { log::warn!("{}", 2+2) }"#,
+        );
+        check_edit(
+            r#""{2+2}".loge"#,
             r#"fn main() { "{2+2}".$0 }"#,
             r#"fn main() { log::error!("{}", 2+2) }"#,
         );
@@ -800,21 +822,21 @@ fn main() {
 
         check_edit_with_config(
             CompletionConfig { snippets: vec![snippet.clone()], ..TEST_CONFIG },
-            "ok",
+            "&&42.ok",
             r#"fn main() { &&42.o$0 }"#,
             r#"fn main() { Ok(&&42) }"#,
         );
 
         check_edit_with_config(
             CompletionConfig { snippets: vec![snippet.clone()], ..TEST_CONFIG },
-            "ok",
+            "&&42.ok",
             r#"fn main() { &&42.$0 }"#,
             r#"fn main() { Ok(&&42) }"#,
         );
 
         check_edit_with_config(
             CompletionConfig { snippets: vec![snippet], ..TEST_CONFIG },
-            "ok",
+            "&a.a.ok",
             r#"
 struct A {
     a: i32,

crates/ide-completion/src/completions/postfix/format_like.rs

@@ -48,10 +48,11 @@ pub(crate) fn add_format_like_completions(
     cap: SnippetCap,
     receiver_text: &ast::String,
 ) {
-    let postfix_snippet = match build_postfix_snippet_builder(ctx, cap, dot_receiver) {
-        Some(it) => it,
-        None => return,
-    };
+    let postfix_snippet =
+        match build_postfix_snippet_builder(ctx, cap, dot_receiver, receiver_text.text()) {
+            Some(it) => it,
+            None => return,
+        };
 
     if let Ok((mut out, mut exprs)) = parse_format_exprs(receiver_text.text()) {
         // Escape any snippet bits in the out text and any of the exprs.