Inline all format arguments where possible

This makes code more readale and concise,
moving all format arguments like `format!("{}", foo)`
into the more compact `format!("{foo}")` form.

The change was automatically created with, so there are far less change
of an accidental typo.

```
cargo clippy --fix -- -A clippy::all -W clippy::uninlined_format_args
```

crates/rust-analyzer/src/bin/logger.rs

@@ -81,9 +81,9 @@ impl Logger {
                 Registry::default()
                     .with(
                         self.filter
-                            .add_directive(format!("chalk_solve={}", val).parse()?)
-                            .add_directive(format!("chalk_ir={}", val).parse()?)
-                            .add_directive(format!("chalk_recursive={}", val).parse()?),
+                            .add_directive(format!("chalk_solve={val}").parse()?)
+                            .add_directive(format!("chalk_ir={val}").parse()?)
+                            .add_directive(format!("chalk_recursive={val}").parse()?),
                     )
                     .with(ra_fmt_layer)
                     .with(chalk_layer)
@@ -124,7 +124,7 @@ where
             Some(log) => log.target(),
             None => event.metadata().target(),
         };
-        write!(writer, "[{} {}] ", level, target)?;
+        write!(writer, "[{level} {target}] ")?;
 
         // Write spans and fields of each span
         ctx.visit_spans(|span| {
@@ -140,7 +140,7 @@ where
             let fields = &ext.get::<FormattedFields<N>>().expect("will never be `None`");
 
             if !fields.is_empty() {
-                write!(writer, "{{{}}}", fields)?;
+                write!(writer, "{{{fields}}}")?;
             }
             write!(writer, ": ")?;
 

crates/rust-analyzer/src/bin/main.rs

@@ -30,7 +30,7 @@ fn main() {
         let code = match rustc_wrapper::run_rustc_skipping_cargo_checking(rustc, args.collect()) {
             Ok(rustc_wrapper::ExitCode(code)) => code.unwrap_or(102),
             Err(err) => {
-                eprintln!("{}", err);
+                eprintln!("{err}");
                 101
             }
         };
@@ -40,7 +40,7 @@ fn main() {
     let flags = flags::RustAnalyzer::from_env_or_exit();
     if let Err(err) = try_main(flags) {
         tracing::error!("Unexpected error: {}", err);
-        eprintln!("{}", err);
+        eprintln!("{err}");
         process::exit(101);
     }
 }

crates/rust-analyzer/src/cli.rs

@@ -46,7 +46,7 @@ fn report_metric(metric: &str, value: u64, unit: &str) {
     if std::env::var("RA_METRICS").is_err() {
         return;
     }
-    println!("METRIC:{}:{}:{}", metric, value, unit)
+    println!("METRIC:{metric}:{value}:{unit}")
 }
 
 fn print_memory_usage(mut host: AnalysisHost, vfs: Vfs) {
@@ -65,6 +65,6 @@ fn print_memory_usage(mut host: AnalysisHost, vfs: Vfs) {
 
     for (name, bytes) in mem {
         // NOTE: Not a debug print, so avoid going through the `eprintln` defined above.
-        eprintln!("{:>8} {}", bytes, name);
+        eprintln!("{bytes:>8} {name}");
     }
 }

crates/rust-analyzer/src/cli/analysis_stats.rs

@@ -87,9 +87,9 @@ impl flags::AnalysisStats {
             load_workspace(workspace, &cargo_config.extra_env, &load_cargo_config)?;
         let db = host.raw_database();
         eprint!("{:<20} {}", "Database loaded:", db_load_sw.elapsed());
-        eprint!(" (metadata {}", metadata_time);
+        eprint!(" (metadata {metadata_time}");
         if let Some(build_scripts_time) = build_scripts_time {
-            eprint!("; build {}", build_scripts_time);
+            eprint!("; build {build_scripts_time}");
         }
         eprintln!(")");
 
@@ -118,7 +118,7 @@ impl flags::AnalysisStats {
             shuffle(&mut rng, &mut visit_queue);
         }
 
-        eprint!("  crates: {}", num_crates);
+        eprint!("  crates: {num_crates}");
         let mut num_decls = 0;
         let mut funcs = Vec::new();
         while let Some(module) = visit_queue.pop() {
@@ -142,7 +142,7 @@ impl flags::AnalysisStats {
                 }
             }
         }
-        eprintln!(", mods: {}, decls: {}, fns: {}", visited_modules.len(), num_decls, funcs.len());
+        eprintln!(", mods: {}, decls: {num_decls}, fns: {}", visited_modules.len(), funcs.len());
         eprintln!("{:<20} {}", "Item Collection:", analysis_sw.elapsed());
 
         if self.randomize {
@@ -154,7 +154,7 @@ impl flags::AnalysisStats {
         }
 
         let total_span = analysis_sw.elapsed();
-        eprintln!("{:<20} {}", "Total:", total_span);
+        eprintln!("{:<20} {total_span}", "Total:");
         report_metric("total time", total_span.time.as_millis() as u64, "ms");
         if let Some(instructions) = total_span.instructions {
             report_metric("total instructions", instructions, "#instr");
@@ -179,7 +179,7 @@ impl flags::AnalysisStats {
                     total_macro_file_size += syntax_len(val.syntax_node())
                 }
             }
-            eprintln!("source files: {}, macro files: {}", total_file_size, total_macro_file_size);
+            eprintln!("source files: {total_file_size}, macro files: {total_macro_file_size}");
         }
 
         if self.memory_usage && verbosity.is_verbose() {
@@ -239,7 +239,7 @@ impl flags::AnalysisStats {
                     continue;
                 }
             }
-            let mut msg = format!("processing: {}", full_name);
+            let mut msg = format!("processing: {full_name}");
             if verbosity.is_verbose() {
                 if let Some(src) = f.source(db) {
                     let original_file = src.file_id.original_file(db);
@@ -275,7 +275,7 @@ impl flags::AnalysisStats {
                                 end.col,
                             ));
                         } else {
-                            bar.println(format!("{}: Unknown type", name,));
+                            bar.println(format!("{name}: Unknown type",));
                         }
                     }
                     true
@@ -402,7 +402,7 @@ fn location_csv(
     let text_range = original_range.range;
     let (start, end) =
         (line_index.line_col(text_range.start()), line_index.line_col(text_range.end()));
-    format!("{},{}:{},{}:{}", path, start.line + 1, start.col, end.line + 1, end.col)
+    format!("{path},{}:{},{}:{}", start.line + 1, start.col, end.line + 1, end.col)
 }
 
 fn expr_syntax_range(

crates/rust-analyzer/src/cli/diagnostics.rs

@@ -40,7 +40,7 @@ impl flags::Diagnostics {
             if !visited_files.contains(&file_id) {
                 let crate_name =
                     module.krate().display_name(db).as_deref().unwrap_or("unknown").to_string();
-                println!("processing crate: {}, module: {}", crate_name, _vfs.file_path(file_id));
+                println!("processing crate: {crate_name}, module: {}", _vfs.file_path(file_id));
                 for diagnostic in analysis
                     .diagnostics(
                         &DiagnosticsConfig::test_sample(),
@@ -53,7 +53,7 @@ impl flags::Diagnostics {
                         found_error = true;
                     }
 
-                    println!("{:?}", diagnostic);
+                    println!("{diagnostic:?}");
                 }
 
                 visited_files.insert(file_id);

crates/rust-analyzer/src/cli/flags.rs

@@ -255,7 +255,7 @@ impl FromStr for OutputFormat {
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         match s {
             "csv" => Ok(Self::Csv),
-            _ => Err(format!("unknown output format `{}`", s)),
+            _ => Err(format!("unknown output format `{s}`")),
         }
     }
 }

crates/rust-analyzer/src/cli/highlight.rs

@@ -8,7 +8,7 @@ impl flags::Highlight {
     pub fn run(self) -> anyhow::Result<()> {
         let (analysis, file_id) = Analysis::from_single_file(read_stdin()?);
         let html = analysis.highlight_as_html(file_id, self.rainbow).unwrap();
-        println!("{}", html);
+        println!("{html}");
         Ok(())
     }
 }

crates/rust-analyzer/src/cli/lsif.rs

@@ -83,7 +83,7 @@ impl LsifManager<'_> {
 
     // FIXME: support file in addition to stdout here
     fn emit(&self, data: &str) {
-        println!("{}", data);
+        println!("{data}");
     }
 
     fn get_token_id(&mut self, id: TokenId) -> Id {

crates/rust-analyzer/src/cli/progress_report.rs

@@ -67,7 +67,7 @@ impl ProgressReport {
             return;
         }
         let percent = (self.curr * 100.0) as u32;
-        let text = format!("{}/{} {:3>}% {}", self.pos, self.len, percent, self.msg);
+        let text = format!("{}/{} {percent:3>}% {}", self.pos, self.len, self.msg);
         self.update_text(&text);
     }
 
@@ -114,7 +114,7 @@ impl ProgressReport {
         // Fill all last text to space and return the cursor
         let spaces = " ".repeat(self.text.len());
         let backspaces = "\x08".repeat(self.text.len());
-        print!("{}{}{}", backspaces, spaces, backspaces);
+        print!("{backspaces}{spaces}{backspaces}");
         let _ = io::stdout().flush();
 
         self.text = String::new();

crates/rust-analyzer/src/cli/scip.rs

@@ -28,7 +28,7 @@ impl flags::Scip {
         let now = Instant::now();
         let cargo_config = CargoConfig::default();
 
-        let no_progress = &|s| (eprintln!("rust-analyzer: Loading {}", s));
+        let no_progress = &|s| (eprintln!("rust-analyzer: Loading {s}"));
         let load_cargo_config = LoadCargoConfig {
             load_out_dirs_from_check: true,
             with_proc_macro: true,
@@ -209,7 +209,7 @@ fn new_descriptor_str(
 fn new_descriptor(name: Name, suffix: scip_types::descriptor::Suffix) -> scip_types::Descriptor {
     let mut name = name.to_string();
     if name.contains("'") {
-        name = format!("`{}`", name);
+        name = format!("`{name}`");
     }
 
     new_descriptor_str(name.as_str(), suffix)
@@ -303,11 +303,11 @@ mod test {
         }
 
         if expected == "" {
-            assert!(found_symbol.is_none(), "must have no symbols {:?}", found_symbol);
+            assert!(found_symbol.is_none(), "must have no symbols {found_symbol:?}");
             return;
         }
 
-        assert!(found_symbol.is_some(), "must have one symbol {:?}", found_symbol);
+        assert!(found_symbol.is_some(), "must have one symbol {found_symbol:?}");
         let res = found_symbol.unwrap();
         let formatted = format_symbol(res);
         assert_eq!(formatted, expected);

crates/rust-analyzer/src/cli/ssr.rs

@@ -70,7 +70,7 @@ impl flags::Search {
                 let sr = db.source_root(root);
                 for file_id in sr.iter() {
                     for debug_info in match_finder.debug_where_text_equal(file_id, debug_snippet) {
-                        println!("{:#?}", debug_info);
+                        println!("{debug_info:#?}");
                     }
                 }
             }

crates/rust-analyzer/src/cli/symbols.rs

@@ -9,7 +9,7 @@ impl flags::Symbols {
         let (analysis, file_id) = Analysis::from_single_file(text);
         let structure = analysis.file_structure(file_id).unwrap();
         for s in structure {
-            println!("{:?}", s);
+            println!("{s:?}");
         }
         Ok(())
     }

crates/rust-analyzer/src/config.rs

@@ -1869,14 +1869,14 @@ fn schema(fields: &[(&'static str, &'static str, &[&str], &str)]) -> serde_json:
         fn key(f: &str) -> &str {
             f.splitn(2, '_').next().unwrap()
         }
-        assert!(key(f1) <= key(f2), "wrong field order: {:?} {:?}", f1, f2);
+        assert!(key(f1) <= key(f2), "wrong field order: {f1:?} {f2:?}");
     }
 
     let map = fields
         .iter()
         .map(|(field, ty, doc, default)| {
             let name = field.replace('_', ".");
-            let name = format!("rust-analyzer.{}", name);
+            let name = format!("rust-analyzer.{name}");
             let props = field_props(field, ty, doc, default);
             (name, props)
         })
@@ -2166,7 +2166,7 @@ fn field_props(field: &str, ty: &str, doc: &[&str], default: &str) -> serde_json
                 },
             ],
         },
-        _ => panic!("missing entry for {}: {}", ty, default),
+        _ => panic!("missing entry for {ty}: {default}"),
     }
 
     map.into()
@@ -2194,14 +2194,14 @@ Default:
                     name, name, default, doc
                 )
             } else {
-                format!("[[{}]]{} (default: `{}`)::\n+\n--\n{}--\n", name, name, default, doc)
+                format!("[[{name}]]{name} (default: `{default}`)::\n+\n--\n{doc}--\n")
             }
         })
         .collect::<String>()
 }
 
 fn doc_comment_to_string(doc: &[&str]) -> String {
-    doc.iter().map(|it| it.strip_prefix(' ').unwrap_or(it)).map(|it| format!("{}\n", it)).collect()
+    doc.iter().map(|it| it.strip_prefix(' ').unwrap_or(it)).map(|it| format!("{it}\n")).collect()
 }
 
 #[cfg(test)]
@@ -2215,7 +2215,7 @@ mod tests {
     #[test]
     fn generate_package_json_config() {
         let s = Config::json_schema();
-        let schema = format!("{:#}", s);
+        let schema = format!("{s:#}");
         let mut schema = schema
             .trim_start_matches('{')
             .trim_end_matches('}')

crates/rust-analyzer/src/diagnostics/to_proto.rs

@@ -161,7 +161,7 @@ fn resolve_path(
         .iter()
         .find_map(|(from, to)| file_name.strip_prefix(from).map(|file_name| (to, file_name)))
     {
-        Some((to, file_name)) => workspace_root.join(format!("{}{}", to, file_name)),
+        Some((to, file_name)) => workspace_root.join(format!("{to}{file_name}")),
         None => workspace_root.join(file_name),
     }
 }
@@ -218,7 +218,7 @@ fn map_rust_child_diagnostic(
     if !suggested_replacements.is_empty() {
         message.push_str(": ");
         let suggestions =
-            suggested_replacements.iter().map(|suggestion| format!("`{}`", suggestion)).join(", ");
+            suggested_replacements.iter().map(|suggestion| format!("`{suggestion}`")).join(", ");
         message.push_str(&suggestions);
     }
 
@@ -493,7 +493,7 @@ fn rustc_code_description(code: Option<&str>) -> Option<lsp_types::CodeDescripti
             && chars.next().is_none()
     })
     .and_then(|code| {
-        lsp_types::Url::parse(&format!("https://doc.rust-lang.org/error-index.html#{}", code))
+        lsp_types::Url::parse(&format!("https://doc.rust-lang.org/error-index.html#{code}"))
             .ok()
             .map(|href| lsp_types::CodeDescription { href })
     })

crates/rust-analyzer/src/dispatch.rs

@@ -145,7 +145,7 @@ impl<'a> RequestDispatcher<'a> {
         match res {
             Ok(params) => {
                 let panic_context =
-                    format!("\nversion: {}\nrequest: {} {:#?}", version(), R::METHOD, params);
+                    format!("\nversion: {}\nrequest: {} {params:#?}", version(), R::METHOD);
                 Some((req, params, panic_context))
             }
             Err(err) => {

crates/rust-analyzer/src/global_state.rs

@@ -429,6 +429,6 @@ pub(crate) fn file_id_to_url(vfs: &vfs::Vfs, id: FileId) -> Url {
 
 pub(crate) fn url_to_file_id(vfs: &vfs::Vfs, url: &Url) -> Result<FileId> {
     let path = from_proto::vfs_path(url)?;
-    let res = vfs.file_id(&path).ok_or_else(|| format!("file not found: {}", path))?;
+    let res = vfs.file_id(&path).ok_or_else(|| format!("file not found: {path}"))?;
     Ok(res)
 }

crates/rust-analyzer/src/handlers.rs

@@ -730,7 +730,7 @@ pub(crate) fn handle_runnables(
         Some(spec) => {
             for cmd in ["check", "test"] {
                 res.push(lsp_ext::Runnable {
-                    label: format!("cargo {} -p {} --all-targets", cmd, spec.package),
+                    label: format!("cargo {cmd} -p {} --all-targets", spec.package),
                     location: None,
                     kind: lsp_ext::RunnableKind::Cargo,
                     args: lsp_ext::CargoRunnable {
@@ -1146,8 +1146,8 @@ pub(crate) fn handle_code_action_resolve(
         Ok(parsed_data) => parsed_data,
         Err(e) => {
             return Err(invalid_params_error(format!(
-                "Failed to parse action id string '{}': {}",
-                params.id, e
+                "Failed to parse action id string '{}': {e}",
+                params.id
             ))
             .into())
         }
@@ -1191,7 +1191,7 @@ fn parse_action_id(action_id: &str) -> Result<(usize, SingleResolve), String> {
             let assist_kind: AssistKind = assist_kind_string.parse()?;
             let index: usize = match index_string.parse() {
                 Ok(index) => index,
-                Err(e) => return Err(format!("Incorrect index string: {}", e)),
+                Err(e) => return Err(format!("Incorrect index string: {e}")),
             };
             Ok((index, SingleResolve { assist_id: assist_id_string.to_string(), assist_kind }))
         }
@@ -1870,7 +1870,7 @@ fn run_rustfmt(
         .stdout(Stdio::piped())
         .stderr(Stdio::piped())
         .spawn()
-        .context(format!("Failed to spawn {:?}", command))?;
+        .context(format!("Failed to spawn {command:?}"))?;
 
     rustfmt.stdin.as_mut().unwrap().write_all(file.as_bytes())?;
 
@@ -1903,9 +1903,9 @@ fn run_rustfmt(
                     format!(
                         r#"rustfmt exited with:
                            Status: {}
-                           stdout: {}
-                           stderr: {}"#,
-                        output.status, captured_stdout, captured_stderr,
+                           stdout: {captured_stdout}
+                           stderr: {captured_stderr}"#,
+                        output.status,
                     ),
                 )
                 .into())

crates/rust-analyzer/src/integrated_benchmarks.rs

@@ -48,7 +48,7 @@ fn integrated_highlighting_benchmark() {
     let file_id = {
         let file = workspace_to_load.join(file);
         let path = VfsPath::from(AbsPathBuf::assert(file));
-        vfs.file_id(&path).unwrap_or_else(|| panic!("can't find virtual file for {}", path))
+        vfs.file_id(&path).unwrap_or_else(|| panic!("can't find virtual file for {path}"))
     };
 
     {
@@ -102,7 +102,7 @@ fn integrated_completion_benchmark() {
     let file_id = {
         let file = workspace_to_load.join(file);
         let path = VfsPath::from(AbsPathBuf::assert(file));
-        vfs.file_id(&path).unwrap_or_else(|| panic!("can't find virtual file for {}", path))
+        vfs.file_id(&path).unwrap_or_else(|| panic!("can't find virtual file for {path}"))
     };
 
     {

crates/rust-analyzer/src/lib.rs

@@ -55,7 +55,7 @@ pub type Result<T, E = Error> = std::result::Result<T, E>;
 
 pub fn from_json<T: DeserializeOwned>(what: &'static str, json: &serde_json::Value) -> Result<T> {
     let res = serde_json::from_value(json.clone())
-        .map_err(|e| format!("Failed to deserialize {}: {}; {}", what, e, json))?;
+        .map_err(|e| format!("Failed to deserialize {what}: {e}; {json}"))?;
     Ok(res)
 }
 

crates/rust-analyzer/src/lsp_utils.rs

@@ -98,7 +98,7 @@ impl GlobalState {
         });
         let cancellable = Some(cancel_token.is_some());
         let token = lsp_types::ProgressToken::String(
-            cancel_token.unwrap_or_else(|| format!("rustAnalyzer/{}", title)),
+            cancel_token.unwrap_or_else(|| format!("rustAnalyzer/{title}")),
         );
         let work_done_progress = match state {
             Progress::Begin => {

crates/rust-analyzer/src/main_loop.rs

@@ -229,8 +229,8 @@ impl GlobalState {
 
                             message = match &report.crates_currently_indexing[..] {
                                 [crate_name] => Some(format!(
-                                    "{}/{} ({})",
-                                    report.crates_done, report.crates_total, crate_name
+                                    "{}/{} ({crate_name})",
+                                    report.crates_done, report.crates_total
                                 )),
                                 [crate_name, rest @ ..] => Some(format!(
                                     "{}/{} ({} + {} more)",
@@ -516,7 +516,7 @@ impl GlobalState {
                 self.report_progress(
                     "Roots Scanned",
                     state,
-                    Some(format!("{}/{}", n_done, n_total)),
+                    Some(format!("{n_done}/{n_total}")),
                     Some(Progress::fraction(n_done, n_total)),
                     None,
                 )
@@ -587,7 +587,7 @@ impl GlobalState {
                     state,
                     message,
                     None,
-                    Some(format!("rust-analyzer/flycheck/{}", id)),
+                    Some(format!("rust-analyzer/flycheck/{id}")),
                 );
             }
         }

crates/rust-analyzer/src/to_proto.rs

@@ -342,7 +342,7 @@ fn completion_item(
         // by the client. Hex format is used because it is easier to
         // visually compare very large values, which the sort text
         // tends to be since it is the opposite of the score.
-        res.sort_text = Some(format!("{:08x}", sort_score));
+        res.sort_text = Some(format!("{sort_score:08x}"));
     }
 }
 
@@ -1113,7 +1113,7 @@ pub(crate) fn code_action(
         (Some(it), _) => res.edit = Some(snippet_workspace_edit(snap, it)?),
         (None, Some((index, code_action_params))) => {
             res.data = Some(lsp_ext::CodeActionData {
-                id: format!("{}:{}:{}", assist.id.0, assist.id.1.name(), index),
+                id: format!("{}:{}:{index}", assist.id.0, assist.id.1.name()),
                 code_action_params,
             });
         }
@@ -1352,7 +1352,7 @@ pub(crate) fn implementation_title(count: usize) -> String {
     if count == 1 {
         "1 implementation".into()
     } else {
-        format!("{} implementations", count)
+        format!("{count} implementations")
     }
 }
 
@@ -1360,7 +1360,7 @@ pub(crate) fn reference_title(count: usize) -> String {
     if count == 1 {
         "1 reference".into()
     } else {
-        format!("{} references", count)
+        format!("{count} references")
     }
 }
 

crates/rust-analyzer/tests/slow-tests/main.rs

@@ -263,7 +263,7 @@ mod tests {
     for runnable in ["consumer", "dependency", "devdependency"] {
         server.request::<Runnables>(
             RunnablesParams {
-                text_document: server.doc_id(&format!("{}/src/lib.rs", runnable)),
+                text_document: server.doc_id(&format!("{runnable}/src/lib.rs")),
                 position: None,
             },
             json!([
@@ -595,8 +595,8 @@ fn diagnostics_dont_block_typing() {
         return;
     }
 
-    let librs: String = (0..10).map(|i| format!("mod m{};", i)).collect();
-    let libs: String = (0..10).map(|i| format!("//- /src/m{}.rs\nfn foo() {{}}\n\n", i)).collect();
+    let librs: String = (0..10).map(|i| format!("mod m{i};")).collect();
+    let libs: String = (0..10).map(|i| format!("//- /src/m{i}.rs\nfn foo() {{}}\n\n")).collect();
     let server = Project::with_fixture(&format!(
         r#"
 //- /Cargo.toml
@@ -622,7 +622,7 @@ fn main() {{}}
     for i in 0..10 {
         server.notification::<DidOpenTextDocument>(DidOpenTextDocumentParams {
             text_document: TextDocumentItem {
-                uri: server.doc_id(&format!("src/m{}.rs", i)).uri,
+                uri: server.doc_id(&format!("src/m{i}.rs")).uri,
                 language_id: "rust".to_string(),
                 version: 0,
                 text: "/// Docs\nfn foo() {}".to_string(),
@@ -645,7 +645,7 @@ fn main() {{}}
         }]),
     );
     let elapsed = start.elapsed();
-    assert!(elapsed.as_millis() < 2000, "typing enter took {:?}", elapsed);
+    assert!(elapsed.as_millis() < 2000, "typing enter took {elapsed:?}");
 }
 
 #[test]
@@ -942,7 +942,7 @@ fn test_will_rename_files_same_level() {
     let tmp_dir = TestDir::new();
     let tmp_dir_path = tmp_dir.path().to_owned();
     let tmp_dir_str = tmp_dir_path.to_str().unwrap();
-    let base_path = PathBuf::from(format!("file://{}", tmp_dir_str));
+    let base_path = PathBuf::from(format!("file://{tmp_dir_str}"));
 
     let code = r#"
 //- /Cargo.toml

crates/rust-analyzer/tests/slow-tests/sourcegen.rs

@@ -42,7 +42,7 @@ impl Feature {
             for block in comment_blocks {
                 let id = block.id;
                 if let Err(msg) = is_valid_feature_name(&id) {
-                    panic!("invalid feature name: {:?}:\n  {}", id, msg)
+                    panic!("invalid feature name: {id:?}:\n  {msg}")
                 }
                 let doc = block.contents.join("\n");
                 let location = sourcegen::Location { file: path.clone(), line: block.line };
@@ -63,11 +63,11 @@ fn is_valid_feature_name(feature: &str) -> Result<(), String> {
         }
         for short in ["To", "And"] {
             if word == short {
-                return Err(format!("Don't capitalize {:?}", word));
+                return Err(format!("Don't capitalize {word:?}"));
             }
         }
         if !word.starts_with(char::is_uppercase) {
-            return Err(format!("Capitalize {:?}", word));
+            return Err(format!("Capitalize {word:?}"));
         }
     }
     Ok(())

crates/rust-analyzer/tests/slow-tests/support.rs

@@ -216,7 +216,7 @@ impl Server {
     fn send_request_(&self, r: Request) -> Value {
         let id = r.id.clone();
         self.client.sender.send(r.clone().into()).unwrap();
-        while let Some(msg) = self.recv().unwrap_or_else(|Timeout| panic!("timeout: {:?}", r)) {
+        while let Some(msg) = self.recv().unwrap_or_else(|Timeout| panic!("timeout: {r:?}")) {
             match msg {
                 Message::Request(req) => {
                     if req.method == "client/registerCapability" {
@@ -228,19 +228,19 @@ impl Server {
                             continue;
                         }
                     }
-                    panic!("unexpected request: {:?}", req)
+                    panic!("unexpected request: {req:?}")
                 }
                 Message::Notification(_) => (),
                 Message::Response(res) => {
                     assert_eq!(res.id, id);
                     if let Some(err) = res.error {
-                        panic!("error response: {:#?}", err);
+                        panic!("error response: {err:#?}");
                     }
                     return res.result.unwrap();
                 }
             }
         }
-        panic!("no response for {:?}", r);
+        panic!("no response for {r:?}");
     }
     pub(crate) fn wait_until_workspace_is_loaded(self) -> Server {
         self.wait_for_message_cond(1, &|msg: &Message| match msg {

crates/rust-analyzer/tests/slow-tests/testdir.rs

@@ -28,7 +28,7 @@ impl TestDir {
         static CNT: AtomicUsize = AtomicUsize::new(0);
         for _ in 0..100 {
             let cnt = CNT.fetch_add(1, Ordering::Relaxed);
-            let path = base.join(format!("{}_{}", pid, cnt));
+            let path = base.join(format!("{pid}_{cnt}"));
             if path.is_dir() {
                 continue;
             }
@@ -53,7 +53,7 @@ impl Drop for TestDir {
             return;
         }
         remove_dir_all(&self.path).unwrap_or_else(|err| {
-            panic!("failed to remove temporary directory {}: {}", self.path.display(), err)
+            panic!("failed to remove temporary directory {}: {err}", self.path.display())
         })
     }
 }

crates/rust-analyzer/tests/slow-tests/tidy.rs

@@ -216,18 +216,18 @@ Zlib OR Apache-2.0 OR MIT
         diff.push_str("New Licenses:\n");
         for &l in licenses.iter() {
             if !expected.contains(&l) {
-                diff += &format!("  {}\n", l)
+                diff += &format!("  {l}\n")
             }
         }
 
         diff.push_str("\nMissing Licenses:\n");
         for &l in expected.iter() {
             if !licenses.contains(&l) {
-                diff += &format!("  {}\n", l)
+                diff += &format!("  {l}\n")
             }
         }
 
-        panic!("different set of licenses!\n{}", diff);
+        panic!("different set of licenses!\n{diff}");
     }
     assert_eq!(licenses, expected);
 }
@@ -316,7 +316,7 @@ fn check_test_attrs(path: &Path, text: &str) {
         "ide-assists/src/tests/generated.rs",
     ];
     if text.contains("#[ignore") && !need_ignore.iter().any(|p| path.ends_with(p)) {
-        panic!("\ndon't `#[ignore]` tests, see:\n\n    {}\n\n   {}\n", ignore_rule, path.display(),)
+        panic!("\ndon't `#[ignore]` tests, see:\n\n    {ignore_rule}\n\n   {}\n", path.display(),)
     }
 
     let panic_rule =
@@ -438,7 +438,7 @@ impl TidyMarks {
             self.hits.symmetric_difference(&self.checks).map(|it| it.as_str()).collect();
 
         if !diff.is_empty() {
-            panic!("unpaired marks: {:?}", diff)
+            panic!("unpaired marks: {diff:?}")
         }
     }
 }