Fix manual_map at the end of an if chain

clippy_lints/src/manual_map.rs

@@ -2,7 +2,7 @@ use crate::{map_unit_fn::OPTION_MAP_UNIT_FN, matches::MATCH_AS_REF};
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::{snippet_with_applicability, snippet_with_context};
 use clippy_utils::ty::{can_partially_move_ty, is_type_diagnostic_item, peel_mid_ty_refs_is_mutable};
-use clippy_utils::{is_allowed, is_else_clause_of_if_let_else, match_def_path, match_var, paths, peel_hir_expr_refs};
+use clippy_utils::{is_allowed, is_else_clause, match_def_path, match_var, paths, peel_hir_expr_refs};
 use rustc_ast::util::parser::PREC_POSTFIX;
 use rustc_errors::Applicability;
 use rustc_hir::{
@@ -181,8 +181,7 @@ impl LateLintPass<'_> for ManualMap {
                 expr.span,
                 "manual implementation of `Option::map`",
                 "try this",
-                if matches!(match_kind, MatchSource::IfLetDesugar { .. }) && is_else_clause_of_if_let_else(cx.tcx, expr)
-                {
+                if matches!(match_kind, MatchSource::IfLetDesugar { .. }) && is_else_clause(cx.tcx, expr) {
                     format!("{{ {}{}.map({}) }}", scrutinee_str, as_ref_str, body_str)
                 } else {
                     format!("{}{}.map({})", scrutinee_str, as_ref_str, body_str)

clippy_utils/src/lib.rs

@@ -797,22 +797,29 @@ pub fn get_parent_as_impl(tcx: TyCtxt<'_>, id: HirId) -> Option<&Impl<'_>> {
     }
 }
 
-/// Checks if the given expression is the else clause in the expression `if let .. {} else {}`
-pub fn is_else_clause_of_if_let_else(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
+/// Checks if the given expression is the else clause of either an `if` or `if let` expression.
+pub fn is_else_clause(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
     let map = tcx.hir();
     let mut iter = map.parent_iter(expr.hir_id);
-    let arm_id = match iter.next() {
-        Some((id, Node::Arm(..))) => id,
-        _ => return false,
-    };
     match iter.next() {
+        Some((arm_id, Node::Arm(..))) => matches!(
+            iter.next(),
+            Some((
+                _,
+                Node::Expr(Expr {
+                    kind: ExprKind::Match(_, [_, else_arm], MatchSource::IfLetDesugar { .. }),
+                    ..
+                })
+            ))
+            if else_arm.hir_id == arm_id
+        ),
         Some((
             _,
             Node::Expr(Expr {
-                kind: ExprKind::Match(_, [_, else_arm], kind),
+                kind: ExprKind::If(_, _, Some(else_expr)),
                 ..
             }),
-        )) => else_arm.hir_id == arm_id && matches!(kind, MatchSource::IfLetDesugar { .. }),
+        )) => else_expr.hir_id == expr.hir_id,
         _ => false,
     }
 }

tests/ui/manual_map_option.fixed

@@ -133,4 +133,8 @@ fn main() {
     if Some(0).is_some() {
         Some(0)
     } else { Some(0).map(|x| x + 1) };
+
+    if true {
+        Some(0)
+    } else { Some(0).map(|x| x + 1) };
 }

tests/ui/manual_map_option.rs

@@ -195,4 +195,12 @@ fn main() {
     } else {
         None
     };
+
+    if true {
+        Some(0)
+    } else if let Some(x) = Some(0) {
+        Some(x + 1)
+    } else {
+        None
+    };
 }

tests/ui/manual_map_option.stderr

@@ -191,5 +191,16 @@ LL | |         None
 LL | |     };
    | |_____^ help: try this: `{ Some(0).map(|x| x + 1) }`
 
-error: aborting due to 21 previous errors
+error: manual implementation of `Option::map`
+  --> $DIR/manual_map_option.rs:201:12
+   |
+LL |       } else if let Some(x) = Some(0) {
+   |  ____________^
+LL | |         Some(x + 1)
+LL | |     } else {
+LL | |         None
+LL | |     };
+   | |_____^ help: try this: `{ Some(0).map(|x| x + 1) }`
+
+error: aborting due to 22 previous errors