Address reviews

Author: Michael Wright

clippy_lints/src/loops.rs

@@ -488,7 +488,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Loops {
                 },
                 NeverLoopResult::MayContinueMainLoop | NeverLoopResult::Otherwise => (),
             }
-        };
+        }
 
         // check for `loop { if let {} else break }` that could be `while let`
         // (also matches an explicit "match" instead of "if let")
@@ -587,16 +587,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Loops {
             }
         }
 
-        if_chain! {
-            if let ExprKind::Loop(block, _, LoopSource::While) = &expr.node;
-            if let Block { expr: Some(expr), .. } = &**block;
-            if let ExprKind::Match(cond, arms, MatchSource::WhileDesugar) = &expr.node;
-            if let ExprKind::DropTemps(cond) = &cond.node;
-            if let [arm, ..] = &arms[..];
-            if let Arm { body, .. } = arm;
-            then {
-                check_infinite_loop(cx, cond, body);
-            }
+        if let Some((cond, body)) = higher::while_loop(&expr) {
+            check_infinite_loop(cx, cond, body);
         }
 
         check_needless_collect(expr, cx);

clippy_lints/src/utils/author.rs

@@ -702,7 +702,7 @@ fn loop_desugaring_name(des: hir::LoopSource) -> &'static str {
     match des {
         hir::LoopSource::ForLoop => "LoopSource::ForLoop",
         hir::LoopSource::Loop => "LoopSource::Loop",
-        hir::LoopSource::While => "LoopSource::WhileDesugar",
+        hir::LoopSource::While => "LoopSource::While",
         hir::LoopSource::WhileLet => "LoopSource::WhileLet",
     }
 }

clippy_lints/src/utils/higher.rs

@@ -199,6 +199,23 @@ pub fn for_loop(expr: &hir::Expr) -> Option<(&hir::Pat, &hir::Expr, &hir::Expr)>
     None
 }
 
+/// Recover the essential nodes of a desugared while loop:
+/// `while cond { body }` becomes `(cond, body)`.
+pub fn while_loop(expr: &hir::Expr) -> Option<(&hir::Expr, &hir::Expr)> {
+    if_chain! {
+        if let hir::ExprKind::Loop(block, _, hir::LoopSource::While) = &expr.node;
+        if let hir::Block { expr: Some(expr), .. } = &**block;
+        if let hir::ExprKind::Match(cond, arms, hir::MatchSource::WhileDesugar) = &expr.node;
+        if let hir::ExprKind::DropTemps(cond) = &cond.node;
+        if let [arm, ..] = &arms[..];
+        if let hir::Arm { body, .. } = arm;
+        then {
+            return Some((cond, body));
+        }
+    }
+    None
+}
+
 /// Recover the essential nodes of a desugared if block
 /// `if cond { then } else { els }` becomes `(cond, then, Some(els))`
 pub fn if_block(expr: &hir::Expr) -> Option<(&hir::Expr, &hir::Expr, Option<&hir::Expr>)> {