Manual collapsing of if and if let expressions containing comments

Those are warned about but not autofixed as the comments inside the `if`
conditions would be lost.

Author: samueltardieu

clippy_lints/src/casts/cast_ptr_alignment.rs

@@ -19,16 +19,15 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>) {
             cx.typeck_results().expr_ty(expr),
         );
         lint_cast_ptr_alignment(cx, expr, cast_from, cast_to);
-    } else if let ExprKind::MethodCall(method_path, self_arg, [], _) = &expr.kind {
-        if method_path.ident.name.as_str() == "cast"
+    } else if let ExprKind::MethodCall(method_path, self_arg, [], _) = &expr.kind
+        && method_path.ident.name.as_str() == "cast"
             && let Some(generic_args) = method_path.args
             && let [GenericArg::Type(cast_to)] = generic_args.args
             // There probably is no obvious reason to do this, just to be consistent with `as` cases.
             && !is_hir_ty_cfg_dependant(cx, cast_to.as_unambig_ty())
-        {
-            let (cast_from, cast_to) = (cx.typeck_results().expr_ty(self_arg), cx.typeck_results().expr_ty(expr));
-            lint_cast_ptr_alignment(cx, expr, cast_from, cast_to);
-        }
+    {
+        let (cast_from, cast_to) = (cx.typeck_results().expr_ty(self_arg), cx.typeck_results().expr_ty(expr));
+        lint_cast_ptr_alignment(cx, expr, cast_from, cast_to);
     }
 }
 

clippy_lints/src/mem_replace.rs

@@ -305,14 +305,12 @@ impl<'tcx> LateLintPass<'tcx> for MemReplace {
             && let ExprKind::Path(ref func_qpath) = func.kind
             && let Some(def_id) = cx.qpath_res(func_qpath, func.hir_id).opt_def_id()
             && cx.tcx.is_diagnostic_item(sym::mem_replace, def_id)
-        {
             // Check that second argument is `Option::None`
-            if !check_replace_option_with_none(cx, src, dest, expr.span)
+            && !check_replace_option_with_none(cx, src, dest, expr.span)
                 && !check_replace_option_with_some(cx, src, dest, expr.span, &self.msrv)
                 && !check_replace_with_default(cx, src, dest, expr, &self.msrv)
-            {
-                check_replace_with_uninit(cx, src, dest, expr.span);
-            }
+        {
+            check_replace_with_uninit(cx, src, dest, expr.span);
         }
     }
     extract_msrv_attr!(LateContext);

clippy_lints/src/missing_fields_in_debug.rs

@@ -224,11 +224,11 @@ impl<'tcx> LateLintPass<'tcx> for MissingFieldsInDebug {
             // NB: can't call cx.typeck_results() as we are not in a body
             && let typeck_results = cx.tcx.typeck_body(*body_id)
             && should_lint(cx, typeck_results, block)
-        {
+        &&
             // we intentionally only lint structs, see lint description
-            if let ItemKind::Struct(data, _) = &self_item.kind {
-                check_struct(cx, typeck_results, block, self_ty, item, data);
-            }
+            let ItemKind::Struct(data, _) = &self_item.kind
+        {
+            check_struct(cx, typeck_results, block, self_ty, item, data);
         }
     }
 }