v1.0 with SW PWA enabled

frontend/node_modules/@jridgewell/trace-mapping/src/by-source.ts

@@ -1,21 +1,17 @@
 import { COLUMN, SOURCES_INDEX, SOURCE_LINE, SOURCE_COLUMN } from './sourcemap-segment';
-import { memoizedBinarySearch, upperBound } from './binary-search';
+import { sortComparator } from './sort';
 
 import type { ReverseSegment, SourceMapSegment } from './sourcemap-segment';
-import type { MemoState } from './binary-search';
 
-export type Source = {
-  __proto__: null;
-  [line: number]: Exclude<ReverseSegment, [number]>[];
-};
+export type Source = ReverseSegment[][];
 
 // Rebuilds the original source files, with mappings that are ordered by source line/column instead
 // of generated line/column.
 export default function buildBySources(
   decoded: readonly SourceMapSegment[][],
-  memos: MemoState[],
+  memos: unknown[],
 ): Source[] {
-  const sources: Source[] = memos.map(buildNullArray);
+  const sources: Source[] = memos.map(() => []);
 
   for (let i = 0; i < decoded.length; i++) {
     const line = decoded[i];
@@ -26,40 +22,20 @@ export default function buildBySources(
       const sourceIndex = seg[SOURCES_INDEX];
       const sourceLine = seg[SOURCE_LINE];
       const sourceColumn = seg[SOURCE_COLUMN];
-      const originalSource = sources[sourceIndex];
-      const originalLine = (originalSource[sourceLine] ||= []);
-      const memo = memos[sourceIndex];
 
-      // The binary search either found a match, or it found the left-index just before where the
-      // segment should go. Either way, we want to insert after that. And there may be multiple
-      // generated segments associated with an original location, so there may need to move several
-      // indexes before we find where we need to insert.
-      let index = upperBound(
-        originalLine,
-        sourceColumn,
-        memoizedBinarySearch(originalLine, sourceColumn, memo, sourceLine),
-      );
+      const source = sources[sourceIndex];
+      const segs = (source[sourceLine] ||= []);
+      segs.push([sourceColumn, i, seg[COLUMN]]);
+    }
+  }
 
-      memo.lastIndex = ++index;
-      insert(originalLine, index, [sourceColumn, i, seg[COLUMN]]);
+  for (let i = 0; i < sources.length; i++) {
+    const source = sources[i];
+    for (let j = 0; j < source.length; j++) {
+      const line = source[j];
+      if (line) line.sort(sortComparator);
     }
   }
 
   return sources;
 }
-
-function insert<T>(array: T[], index: number, value: T) {
-  for (let i = array.length; i > index; i--) {
-    array[i] = array[i - 1];
-  }
-  array[index] = value;
-}
-
-// Null arrays allow us to use ordered index keys without actually allocating contiguous memory like
-// a real array. We use a null-prototype object to avoid prototype pollution and deoptimizations.
-// Numeric properties on objects are magically sorted in ascending order by the engine regardless of
-// the insertion order. So, by setting any numeric keys, even out of order, we'll get ascending
-// order when iterating with for-in.
-function buildNullArray<T extends { __proto__: null }>(): T {
-  return { __proto__: null } as T;
-}

frontend/node_modules/@jridgewell/trace-mapping/src/sort.ts

@@ -1,6 +1,6 @@
 import { COLUMN } from './sourcemap-segment';
 
-import type { SourceMapSegment } from './sourcemap-segment';
+import type { ReverseSegment, SourceMapSegment } from './sourcemap-segment';
 
 export default function maybeSort(
   mappings: SourceMapSegment[][],
@@ -40,6 +40,6 @@ function sortSegments(line: SourceMapSegment[], owned: boolean): SourceMapSegmen
   return line.sort(sortComparator);
 }
 
-function sortComparator(a: SourceMapSegment, b: SourceMapSegment): number {
+export function sortComparator<T extends SourceMapSegment | ReverseSegment>(a: T, b: T): number {
   return a[COLUMN] - b[COLUMN];
 }

frontend/node_modules/@jridgewell/trace-mapping/src/trace-mapping.ts

@@ -484,15 +484,13 @@ function generatedPosition(
   if (sourceIndex === -1) sourceIndex = resolvedSources.indexOf(source);
   if (sourceIndex === -1) return all ? [] : GMapping(null, null);
 
-  const generated = (cast(map)._bySources ||= buildBySources(
-    decodedMappings(map),
-    (cast(map)._bySourceMemos = sources.map(memoizedState)),
-  ));
+  const bySourceMemos = (cast(map)._bySourceMemos ||= sources.map(memoizedState));
+  const generated = (cast(map)._bySources ||= buildBySources(decodedMappings(map), bySourceMemos));
 
   const segments = generated[sourceIndex][line];
   if (segments == null) return all ? [] : GMapping(null, null);
 
-  const memo = cast(map)._bySourceMemos![sourceIndex];
+  const memo = bySourceMemos[sourceIndex];
 
   if (all) return sliceGeneratedPositions(segments, memo, line, column, bias);