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Author: estebank

compiler/rustc_lint/src/default_could_be_derived.rs

@@ -263,14 +263,21 @@ impl<'tcx> LateLintPass<'tcx> for DefaultCouldBeDerived {
                     if idx > 0
                         && let Some(prev_field) = fields.get(idx - 1)
                     {
+                        // Span covering the current field *and* the prior `,` for the prior field.
                         removals.push(prev_field.span.shrink_to_hi().to(field.span));
                     } else if let Some(next_field) = fields.get(idx + 1) {
+                        // Span for the current field *and* its trailing comma, all the way to the
+                        // next field.
                         removals.push(field.span.until(next_field.span));
                     } else if idx + 1 == fields.len()
                         && let hir::StructTailExpr::DefaultFields(span) = tail
                     {
+                        // This is the last field *and* there's a `, ..`. This span covers this
+                        // entire field and the `, ..`.
                         removals.push(field.span.until(span));
                     } else {
+                        // The span for the current field, without any commas. This is a fallback
+                        // that shouldn't really trigger.
                         removals.push(field.span);
                     }
                 };