Merge #1374

1374: Implement `cargo lint` and fix some clippy errors r=alanhdu a=alanhdu

This creates a `cargo lint` command that runs clippy with certain lints disabled. I've also gone ahead and fixed some of the lint errors, although there are many more still to go.

cc #848 

Co-authored-by: Alan Du <[email protected]>

4 files changed, 16 insertions, 20 deletions

diff --git a/crates/ra_assists/src/ast_editor.rs b/crates/ra_assists/src/ast_editor.rs
index cabb3d862..de0529b32 100644
--- a/crates/ra_assists/src/ast_editor.rs
+++ b/crates/ra_assists/src/ast_editor.rs
@@ -212,21 +212,17 @@ impl AstEditor<ast::FnDef> {
     }
 
     pub fn strip_attrs_and_docs(&mut self) {
-        loop {
-            if let Some(start) = self
-                .ast()
-                .syntax()
-                .children_with_tokens()
-                .find(|it| it.kind() == ATTR || it.kind() == COMMENT)
-            {
-                let end = match start.next_sibling_or_token() {
-                    Some(el) if el.kind() == WHITESPACE => el,
-                    Some(_) | None => start,
-                };
-                self.ast = self.replace_children(RangeInclusive::new(start, end), iter::empty());
-            } else {
-                break;
-            }
+        while let Some(start) = self
+            .ast()
+            .syntax()
+            .children_with_tokens()
+            .find(|it| it.kind() == ATTR || it.kind() == COMMENT)
+        {
+            let end = match start.next_sibling_or_token() {
+                Some(el) if el.kind() == WHITESPACE => el,
+                Some(_) | None => start,
+            };
+            self.ast = self.replace_children(RangeInclusive::new(start, end), iter::empty());
         }
     }
 }
diff --git a/crates/ra_assists/src/auto_import.rs b/crates/ra_assists/src/auto_import.rs
index 1566cf179..9617beb5c 100644
--- a/crates/ra_assists/src/auto_import.rs
+++ b/crates/ra_assists/src/auto_import.rs
@@ -334,7 +334,7 @@ fn best_action_for_target<'b, 'a: 'b>(
         .filter_map(ast::UseItem::use_tree)
         .map(|u| walk_use_tree_for_best_action(&mut storage, None, u, target))
         .fold(None, |best, a| {
-            best.and_then(|best| Some(*ImportAction::better(&best, &a))).or(Some(a))
+            best.and_then(|best| Some(*ImportAction::better(&best, &a))).or_else(|| Some(a))
         });
 
     match best_action {
@@ -347,7 +347,7 @@ fn best_action_for_target<'b, 'a: 'b>(
             let anchor = container
                 .children()
                 .find(|n| n.range().start() < anchor.range().start())
-                .or(Some(anchor));
+                .or_else(|| Some(anchor));
 
             return ImportAction::add_new_use(anchor, false);
         }
diff --git a/crates/ra_assists/src/change_visibility.rs b/crates/ra_assists/src/change_visibility.rs
index 620f534b5..4eb24d27f 100644
--- a/crates/ra_assists/src/change_visibility.rs
+++ b/crates/ra_assists/src/change_visibility.rs
@@ -59,7 +59,7 @@ fn vis_offset(node: &SyntaxNode) -> TextUnit {
         })
         .next()
         .map(|it| it.range().start())
-        .unwrap_or(node.range().start())
+        .unwrap_or_else(|| node.range().start())
 }
 
 fn change_vis(mut ctx: AssistCtx<impl HirDatabase>, vis: &ast::Visibility) -> Option<Assist> {
diff --git a/crates/ra_assists/src/introduce_variable.rs b/crates/ra_assists/src/introduce_variable.rs
index fb7333c8c..28467d341 100644
--- a/crates/ra_assists/src/introduce_variable.rs
+++ b/crates/ra_assists/src/introduce_variable.rs
@@ -57,9 +57,9 @@ pub(crate) fn introduce_variable(mut ctx: AssistCtx<impl HirDatabase>) -> Option
             if text.starts_with("\r\n") {
                 buf.push_str("\r\n");
                 buf.push_str(text.trim_start_matches("\r\n"));
-            } else if text.starts_with("\n") {
+            } else if text.starts_with('\n') {
                 buf.push_str("\n");
-                buf.push_str(text.trim_start_matches("\n"));
+                buf.push_str(text.trim_start_matches('\n'));
             } else {
                 buf.push_str(text);
             }