edit to use map_while

Author: surechen

clippy_lints/src/large_enum_variant.rs

@@ -139,25 +139,25 @@ impl<'tcx> LateLintPass<'tcx> for LargeEnumVariant {
                             .fields_size
                             .iter()
                             .rev()
-                            .take_while(|val| {
-                                let judge = difference > self.maximum_size_difference_allowed;
-                                difference = difference.saturating_sub(val.size);
-                                judge
-                            })
-                            .map(|val| {
-                                (
-                                    fields[val.ind].ty.span,
-                                    format!(
-                                        "Box<{}>",
-                                        snippet_with_applicability(
-                                            cx,
-                                            fields[val.ind].ty.span,
-                                            "..",
-                                            &mut applicability
-                                        )
-                                        .into_owned()
-                                    ),
-                                )
+                            .map_while(|val| {
+                                if difference > self.maximum_size_difference_allowed {
+                                    difference = difference.saturating_sub(val.size);
+                                    Some((
+                                        fields[val.ind].ty.span,
+                                        format!(
+                                            "Box<{}>",
+                                            snippet_with_applicability(
+                                                cx,
+                                                fields[val.ind].ty.span,
+                                                "..",
+                                                &mut applicability
+                                            )
+                                            .into_owned()
+                                        ),
+                                    ))
+                                } else {
+                                    None
+                                }
                             })
                             .collect();
 

clippy_lints/src/lib.rs

@@ -3,6 +3,7 @@
 #![feature(box_patterns)]
 #![feature(drain_filter)]
 #![feature(in_band_lifetimes)]
+#![feature(iter_map_while)]
 #![feature(iter_zip)]
 #![feature(once_cell)]
 #![feature(rustc_private)]