use syntax::ast::*;
use syntax::codemap::Spanned;
use utils::{span_lint_and_sugg, snippet};
-
+use std::ops::Deref;
/// **What it does:** Checks for
/// - () being assigned to a variable
impl EarlyLintPass for UnitExpr {
fn check_expr(&mut self, cx: &EarlyContext, expr: &Expr) {
- if let ExprKind::Assign(ref left, ref right) = expr.node {
+ if let ExprKind::Assign(ref _left, ref right) = expr.node {
if is_unit_expr(right){
span_lint_and_sugg(
cx,
)
}
}
- if let ExprKind::MethodCall(_, ref args) = expr.node {
+ if let ExprKind::MethodCall(ref _left, ref args) = expr.node {
for ref arg in args{
if is_unit_expr(arg){
span_lint_and_sugg(
fn is_unit_expr(expr: &Expr)->bool{
match expr.node{
- ExprKind::Block(ref next) => {
- let ref final_stmt = &next.stmts[next.stmts.len()-1];
- if let StmtKind::Expr(_) = final_stmt.node{
+ ExprKind::Block(ref block) => {
+ return check_last_stmt_in_block(block);
+ },
+ ExprKind::If(_, ref then, ref else_)=>{
+ let check_then = check_last_stmt_in_block(then);
+ if let Some(ref else_) = *else_{
+ return check_then && is_unit_expr(else_.deref());
+ }
+ return check_then;
+ }
+ _ => return false,
+ }
+}
+
+fn check_last_stmt_in_block(block: &Block)->bool{
+ let ref final_stmt = &block.stmts[block.stmts.len()-1];
+ if let StmtKind::Expr(_) = final_stmt.node{
return false;
}
else{
return true;
}
- },
- _ => return false,
- }
}
\ No newline at end of file