Remove some unnecessary If arms

Author: Manishearth

clippy_lints/src/implicit_return.rs

@@ -74,13 +74,6 @@ impl ImplicitReturn {
                     Self::lint(cx, expr.span, break_expr.span, "change `break` to `return` as shown");
                 }
             },
-            ExprKind::If(.., if_expr, else_expr) => {
-                Self::expr_match(cx, if_expr);
-
-                if let Some(else_expr) = else_expr {
-                    Self::expr_match(cx, else_expr);
-                }
-            },
             ExprKind::Match(.., arms, source) => {
                 let check_all_arms = match source {
                     MatchSource::IfLetDesugar {

clippy_lints/src/loops.rs

@@ -686,14 +686,6 @@ fn never_loop_expr(expr: &Expr, main_loop_id: HirId) -> NeverLoopResult {
         | ExprKind::Assign(ref e1, ref e2)
         | ExprKind::AssignOp(_, ref e1, ref e2)
         | ExprKind::Index(ref e1, ref e2) => never_loop_expr_all(&mut [&**e1, &**e2].iter().cloned(), main_loop_id),
-        ExprKind::If(ref e, ref e2, ref e3) => {
-            let e1 = never_loop_expr(e, main_loop_id);
-            let e2 = never_loop_expr(e2, main_loop_id);
-            let e3 = e3
-                .as_ref()
-                .map_or(NeverLoopResult::Otherwise, |e| never_loop_expr(e, main_loop_id));
-            combine_seq(e1, combine_branches(e2, e3))
-        },
         ExprKind::Loop(ref b, _, _) => {
             // Break can come from the inner loop so remove them.
             absorb_break(&never_loop_block(b, main_loop_id))
@@ -2204,7 +2196,7 @@ fn is_loop(expr: &Expr) -> bool {
 
 fn is_conditional(expr: &Expr) -> bool {
     match expr.node {
-        ExprKind::If(..) | ExprKind::Match(..) => true,
+        ExprKind::Match(..) => true,
         _ => false,
     }
 }

clippy_lints/src/methods/mod.rs

@@ -1266,7 +1266,6 @@ fn lint_expect_fun_call(cx: &LateContext<'_, '_>, expr: &hir::Expr, method_span:
             hir::ExprKind::Call(..)
             | hir::ExprKind::MethodCall(..)
             // These variants are debatable or require further examination
-            | hir::ExprKind::If(..)
             | hir::ExprKind::Match(..)
             | hir::ExprKind::Block{ .. } => true,
             _ => false,

clippy_lints/src/methods/unnecessary_filter_map.rs

@@ -89,12 +89,6 @@ fn check_expression<'a, 'tcx: 'a>(
                 (false, false)
             }
         },
-        // There must be an else_arm or there will be a type error
-        hir::ExprKind::If(_, ref if_arm, Some(ref else_arm)) => {
-            let if_check = check_expression(cx, arg_id, if_arm);
-            let else_check = check_expression(cx, arg_id, else_arm);
-            (if_check.0 | else_check.0, if_check.1 | else_check.1)
-        },
         hir::ExprKind::Match(_, ref arms, _) => {
             let mut found_mapping = false;
             let mut found_filtering = false;

clippy_lints/src/utils/hir_utils.rs

@@ -493,15 +493,6 @@ impl<'a, 'tcx: 'a> SpanlessHash<'a, 'tcx> {
                 let c: fn(_, _, _) -> _ = ExprKind::InlineAsm;
                 c.hash(&mut self.s);
             },
-            ExprKind::If(ref cond, ref t, ref e) => {
-                let c: fn(_, _, _) -> _ = ExprKind::If;
-                c.hash(&mut self.s);
-                self.hash_expr(cond);
-                self.hash_expr(&**t);
-                if let Some(ref e) = *e {
-                    self.hash_expr(e);
-                }
-            },
             ExprKind::Lit(ref l) => {
                 let c: fn(_) -> _ = ExprKind::Lit;
                 c.hash(&mut self.s);

clippy_lints/src/utils/inspector.rs

@@ -209,15 +209,6 @@ fn print_expr(cx: &LateContext<'_, '_>, expr: &hir::Expr, indent: usize) {
             print_expr(cx, e, indent + 1);
             println!("{}target type: {:?}", ind, target);
         },
-        hir::ExprKind::If(ref e, _, ref els) => {
-            println!("{}If", ind);
-            println!("{}condition:", ind);
-            print_expr(cx, e, indent + 1);
-            if let Some(ref els) = *els {
-                println!("{}else:", ind);
-                print_expr(cx, els, indent + 1);
-            }
-        },
         hir::ExprKind::While(ref cond, _, _) => {
             println!("{}While", ind);
             println!("{}condition:", ind);

clippy_lints/src/utils/sugg.rs

@@ -94,7 +94,6 @@ impl<'a> Sugg<'a> {
             hir::ExprKind::AddrOf(..)
             | hir::ExprKind::Box(..)
             | hir::ExprKind::Closure(.., _)
-            | hir::ExprKind::If(..)
             | hir::ExprKind::Unary(..)
             | hir::ExprKind::Match(..) => Sugg::MaybeParen(snippet),
             hir::ExprKind::Continue(..)