bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-diagnostics/src/handlers/useless_braces.rs')
-rw-r--r--crates/ide-diagnostics/src/handlers/useless_braces.rs148
1 files changed, 148 insertions, 0 deletions
diff --git a/crates/ide-diagnostics/src/handlers/useless_braces.rs b/crates/ide-diagnostics/src/handlers/useless_braces.rs
new file mode 100644
index 0000000000..8b9330e040
--- /dev/null
+++ b/crates/ide-diagnostics/src/handlers/useless_braces.rs
@@ -0,0 +1,148 @@
+use ide_db::{base_db::FileId, source_change::SourceChange};
+use itertools::Itertools;
+use syntax::{ast, AstNode, SyntaxNode, TextRange};
+use text_edit::TextEdit;
+
+use crate::{fix, Diagnostic, Severity};
+
+// Diagnostic: unnecessary-braces
+//
+// Diagnostic for unnecessary braces in `use` items.
+pub(crate) fn useless_braces(
+ acc: &mut Vec<Diagnostic>,
+ file_id: FileId,
+ node: &SyntaxNode,
+) -> Option<()> {
+ let use_tree_list = ast::UseTreeList::cast(node.clone())?;
+ if let Some((single_use_tree,)) = use_tree_list.use_trees().collect_tuple() {
+ // If there is a comment inside the bracketed `use`,
+ // assume it is a commented out module path and don't show diagnostic.
+ if use_tree_list.has_inner_comment() {
+ return Some(());
+ }
+
+ let use_range = use_tree_list.syntax().text_range();
+ let edit = remove_braces(&single_use_tree).unwrap_or_else(|| {
+ let to_replace = single_use_tree.syntax().text().to_string();
+ let mut edit_builder = TextEdit::builder();
+ edit_builder.delete(use_range);
+ edit_builder.insert(use_range.start(), to_replace);
+ edit_builder.finish()
+ });
+
+ acc.push(
+ Diagnostic::new(
+ "unnecessary-braces",
+ "Unnecessary braces in use statement".to_string(),
+ use_range,
+ )
+ .severity(Severity::WeakWarning)
+ .with_fixes(Some(vec![fix(
+ "remove_braces",
+ "Remove unnecessary braces",
+ SourceChange::from_text_edit(file_id, edit),
+ use_range,
+ )])),
+ );
+ }
+
+ Some(())
+}
+
+fn remove_braces(single_use_tree: &ast::UseTree) -> Option<TextEdit> {
+ let use_tree_list_node = single_use_tree.syntax().parent()?;
+ if single_use_tree.path()?.segment()?.self_token().is_some() {
+ let start = use_tree_list_node.prev_sibling_or_token()?.text_range().start();
+ let end = use_tree_list_node.text_range().end();
+ return Some(TextEdit::delete(TextRange::new(start, end)));
+ }
+ None
+}
+
+#[cfg(test)]
+mod tests {
+ use crate::tests::{check_diagnostics, check_fix};
+
+ #[test]
+ fn test_check_unnecessary_braces_in_use_statement() {
+ check_diagnostics(
+ r#"
+use a;
+use a::{c, d::e};
+
+mod a {
+ mod c {}
+ mod d {
+ mod e {}
+ }
+}
+"#,
+ );
+ check_diagnostics(
+ r#"
+use a;
+use a::{
+ c,
+ // d::e
+};
+
+mod a {
+ mod c {}
+ mod d {
+ mod e {}
+ }
+}
+"#,
+ );
+ check_fix(
+ r#"
+mod b {}
+use {$0b};
+"#,
+ r#"
+mod b {}
+use b;
+"#,
+ );
+ check_fix(
+ r#"
+mod b {}
+use {b$0};
+"#,
+ r#"
+mod b {}
+use b;
+"#,
+ );
+ check_fix(
+ r#"
+mod a { mod c {} }
+use a::{c$0};
+"#,
+ r#"
+mod a { mod c {} }
+use a::c;
+"#,
+ );
+ check_fix(
+ r#"
+mod a {}
+use a::{self$0};
+"#,
+ r#"
+mod a {}
+use a;
+"#,
+ );
+ check_fix(
+ r#"
+mod a { mod c {} mod d { mod e {} } }
+use a::{c, d::{e$0}};
+"#,
+ r#"
+mod a { mod c {} mod d { mod e {} } }
+use a::{c, d::e};
+"#,
+ );
+ }
+}