Some clippy fixes

crates/ra_assists/src/assists/early_return.rs

@@ -50,7 +50,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx<impl HirDatabase>) -> Opt
     }
 
     // check for early return and continue
-    let first_in_then_block = then_block.syntax().first_child()?.clone();
+    let first_in_then_block = then_block.syntax().first_child()?;
     if ast::ReturnExpr::can_cast(first_in_then_block.kind())
         || ast::ContinueExpr::can_cast(first_in_then_block.kind())
         || first_in_then_block

crates/ra_assists/src/assists/inline_local_variable.rs

@@ -51,10 +51,8 @@ pub(crate) fn inline_local_varialbe(ctx: AssistCtx<impl HirDatabase>) -> Option<
     let mut wrap_in_parens = vec![true; refs.len()];
 
     for (i, desc) in refs.iter().enumerate() {
-        let usage_node = ctx
+        let usage_node =
-            .covering_node_for_range(desc.range)
+            ctx.covering_node_for_range(desc.range).ancestors().find_map(ast::PathExpr::cast)?;
-            .ancestors()
-            .find_map(|node| ast::PathExpr::cast(node))?;
         let usage_parent_option = usage_node.syntax().parent().and_then(ast::Expr::cast);
         let usage_parent = match usage_parent_option {
             Some(u) => u,

crates/ra_assists/src/assists/raw_string.rs

@@ -131,7 +131,7 @@ pub(crate) fn remove_hash(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     ctx.add_assist(AssistId("remove_hash"), "remove hash from raw string", |edit| {
         edit.target(token.text_range());
         let result = &text[2..text.len() - 1];
-        let result = if result.starts_with("\"") {
+        let result = if result.starts_with('\"') {
             // no more hash, escape
             let internal_str = &result[1..result.len() - 1];
             format!("\"{}\"", internal_str.escape_default().to_string())

crates/ra_ide_api/src/call_info.rs

@@ -95,7 +95,7 @@ impl FnCallNode {
                 Some(FnCallNode::CallExpr(expr))
             } else if let Some(expr) = ast::MethodCallExpr::cast(node.clone()) {
                 Some(FnCallNode::MethodCallExpr(expr))
-            } else if let Some(expr) = ast::MacroCall::cast(node.clone()) {
+            } else if let Some(expr) = ast::MacroCall::cast(node) {
                 Some(FnCallNode::MacroCallExpr(expr))
             } else {
                 None

crates/ra_ide_api/src/change.rs

@@ -43,7 +43,7 @@ impl fmt::Debug for AnalysisChange {
         if !self.libraries_added.is_empty() {
             d.field("libraries_added", &self.libraries_added.len());
         }
-        if !self.crate_graph.is_some() {
+        if !self.crate_graph.is_none() {
             d.field("crate_graph", &self.crate_graph);
         }
         d.finish()

crates/ra_ide_api/src/completion/complete_path.rs

@@ -67,7 +67,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
                 });
             }
         }
-        _ => return,
+        _ => {}
     };
 }
 

crates/ra_ide_api/src/completion/presentation.rs

@@ -136,7 +136,7 @@ impl Completions {
         for (idx, s) in docs.match_indices(&macro_name) {
             let (before, after) = (&docs[..idx], &docs[idx + s.len()..]);
             // Ensure to match the full word
-            if after.starts_with("!")
+            if after.starts_with('!')
                 && before
                     .chars()
                     .rev()
@@ -225,7 +225,7 @@ impl Completions {
                 } else {
                     (format!("{}($0)", data.name()), format!("{}(…)", name))
                 };
-            builder = builder.lookup_by(name.clone()).label(label).insert_snippet(snippet);
+            builder = builder.lookup_by(name).label(label).insert_snippet(snippet);
         }
 
         self.add(builder)

crates/ra_ide_api/src/references/search_scope.rs

@@ -111,8 +111,7 @@ impl NameDefinition {
         if vis.as_str() != "" {
             let source_root_id = db.file_source_root(file_id);
             let source_root = db.source_root(source_root_id);
-            let mut res =
+            let mut res = source_root.walk().map(|id| (id, None)).collect::<FxHashMap<_, _>>();
-                source_root.walk().map(|id| (id.into(), None)).collect::<FxHashMap<_, _>>();
 
             // FIXME: add "pub(in path)"
 
@@ -128,7 +127,7 @@ impl NameDefinition {
                         let root_file = crate_graph.crate_root(crate_id);
                         let source_root_id = db.file_source_root(root_file);
                         let source_root = db.source_root(source_root_id);
-                        res.extend(source_root.walk().map(|id| (id.into(), None)));
+                        res.extend(source_root.walk().map(|id| (id, None)));
                     }
                 }
                 return SearchScope::new(res);

crates/ra_ide_api/src/typing.rs

@@ -261,7 +261,7 @@ impl S {
 
     fn type_char(char_typed: char, before: &str, after: &str) {
         let (actual, file_change) = do_type_char(char_typed, before)
-            .expect(&format!("typing `{}` did nothing", char_typed));
+            .unwrap_or_else(|| panic!("typing `{}` did nothing", char_typed));
 
         if after.contains("<|>") {
             let (offset, after) = extract_offset(after);

crates/ra_lsp_server/src/main_loop.rs

@@ -196,7 +196,7 @@ pub fn main_loop(
     task_receiver.into_iter().for_each(|task| {
         on_task(task, &connection.sender, &mut loop_state.pending_requests, &mut world_state)
     });
-    libdata_receiver.into_iter().for_each(|lib| drop(lib));
+    libdata_receiver.into_iter().for_each(drop);
     log::info!("...tasks have finished");
     log::info!("joining threadpool...");
     drop(pool);

crates/ra_mbe/src/mbe_expander/matcher.rs

@@ -123,7 +123,6 @@ fn match_subtree(
                     }
                     None => bindings.push_optional(name),
                 }
-                ()
             }
             Op::Repeat { subtree, kind, separator } => {
                 match_repeat(bindings, subtree, kind, separator, src)?
@@ -159,7 +158,7 @@ impl<'a> TtIter<'a> {
     pub(crate) fn expect_lifetime(&mut self) -> Result<&tt::Ident, ()> {
         let ident = self.expect_ident()?;
         // check if it start from "`"
-        if ident.text.chars().next() != Some('\'') {
+        if !ident.text.starts_with('\'') {
             return Err(());
         }
         Ok(ident)

crates/ra_mbe/src/syntax_bridge.rs

@@ -383,7 +383,7 @@ mod tests {
             "#,
         );
         let expansion = expand(&rules, "literals!(foo);");
-        let tts = &[expansion.clone().into()];
+        let tts = &[expansion.into()];
         let buffer = tt::buffer::TokenBuffer::new(tts);
         let mut tt_src = SubtreeTokenSource::new(&buffer);
         let mut tokens = vec![];

crates/ra_syntax/src/ast/make.rs

@@ -129,11 +129,11 @@ pub fn where_clause(preds: impl Iterator<Item = ast::WherePred>) -> ast::WhereCl
 }
 
 pub fn if_expression(condition: &ast::Expr, statement: &str) -> ast::IfExpr {
-    return ast_from_text(&format!(
+    ast_from_text(&format!(
         "fn f() {{ if !{} {{\n    {}\n}}\n}}",
         condition.syntax().text(),
         statement
-    ));
+    ))
 }
 
 fn ast_from_text<N: AstNode>(text: &str) -> N {

xtask/src/codegen/gen_assists_docs.rs

@@ -53,7 +53,7 @@ fn collect_assists() -> Result<Vec<Assist>> {
 
             let doc = take_until(lines.by_ref(), "```").trim().to_string();
             assert!(
-                doc.chars().next().unwrap().is_ascii_uppercase() && doc.ends_with("."),
+                doc.chars().next().unwrap().is_ascii_uppercase() && doc.ends_with('.'),
                 "\n\n{}: assist docs should be proper sentences, with capitalization and a full stop at the end.\n\n{}\n\n",
                 id, doc,
             );

xtask/src/codegen/gen_parser_tests.rs

@@ -102,12 +102,10 @@ fn tests_from_dir(dir: &Path) -> Result<Tests> {
         for test in collect_tests(&text) {
             if test.ok {
                 if let Some(old_test) = res.ok.insert(test.name.clone(), test) {
-                    Err(format!("Duplicate test: {}", old_test.name))?
+                    return Err(format!("Duplicate test: {}", old_test.name).into());
-                }
-            } else {
-                if let Some(old_test) = res.err.insert(test.name.clone(), test) {
-                    Err(format!("Duplicate test: {}", old_test.name))?
                 }
+            } else if let Some(old_test) = res.err.insert(test.name.clone(), test) {
+                return Err(format!("Duplicate test: {}", old_test.name).into());
             }
         }
         Ok(())

xtask/src/main.rs

@@ -60,7 +60,7 @@ fn main() -> Result<()> {
             matches.finish().or_else(handle_extra_flags)?;
             let opts = InstallOpt {
                 client: if server { None } else { Some(ClientOpt::VsCode) },
-                server: if client_code { None } else { Some(ServerOpt { jemalloc: jemalloc }) },
+                server: if client_code { None } else { Some(ServerOpt { jemalloc }) },
             };
             install(opts)?
         }

xtask/tests/tidy-tests/docs.rs

@@ -29,7 +29,7 @@ fn is_exclude_file(d: &DirEntry) -> bool {
 }
 
 fn is_hidden(entry: &DirEntry) -> bool {
-    entry.file_name().to_str().map(|s| s.starts_with(".")).unwrap_or(false)
+    entry.file_name().to_str().map(|s| s.starts_with('.')).unwrap_or(false)
 }
 
 #[test]