initial commit

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

@@ -0,0 +1,192 @@
+import { TraceMap, presortedDecodedMap, decodedMappings } from './trace-mapping';
+import {
+  COLUMN,
+  SOURCES_INDEX,
+  SOURCE_LINE,
+  SOURCE_COLUMN,
+  NAMES_INDEX,
+} from './sourcemap-segment';
+import { parse } from './types';
+
+import type {
+  DecodedSourceMap,
+  DecodedSourceMapXInput,
+  EncodedSourceMapXInput,
+  SectionedSourceMapXInput,
+  SectionedSourceMapInput,
+  SectionXInput,
+  Ro,
+} from './types';
+import type { SourceMapSegment } from './sourcemap-segment';
+
+type FlattenMap = {
+  new (map: Ro<SectionedSourceMapInput>, mapUrl?: string | null): TraceMap;
+  (map: Ro<SectionedSourceMapInput>, mapUrl?: string | null): TraceMap;
+};
+
+export const FlattenMap: FlattenMap = function (map, mapUrl) {
+  const parsed = parse(map as SectionedSourceMapInput);
+
+  if (!('sections' in parsed)) {
+    return new TraceMap(parsed as DecodedSourceMapXInput | EncodedSourceMapXInput, mapUrl);
+  }
+
+  const mappings: SourceMapSegment[][] = [];
+  const sources: string[] = [];
+  const sourcesContent: (string | null)[] = [];
+  const names: string[] = [];
+  const ignoreList: number[] = [];
+
+  recurse(
+    parsed,
+    mapUrl,
+    mappings,
+    sources,
+    sourcesContent,
+    names,
+    ignoreList,
+    0,
+    0,
+    Infinity,
+    Infinity,
+  );
+
+  const joined: DecodedSourceMap = {
+    version: 3,
+    file: parsed.file,
+    names,
+    sources,
+    sourcesContent,
+    mappings,
+    ignoreList,
+  };
+
+  return presortedDecodedMap(joined);
+} as FlattenMap;
+
+function recurse(
+  input: SectionedSourceMapXInput,
+  mapUrl: string | null | undefined,
+  mappings: SourceMapSegment[][],
+  sources: string[],
+  sourcesContent: (string | null)[],
+  names: string[],
+  ignoreList: number[],
+  lineOffset: number,
+  columnOffset: number,
+  stopLine: number,
+  stopColumn: number,
+) {
+  const { sections } = input;
+  for (let i = 0; i < sections.length; i++) {
+    const { map, offset } = sections[i];
+
+    let sl = stopLine;
+    let sc = stopColumn;
+    if (i + 1 < sections.length) {
+      const nextOffset = sections[i + 1].offset;
+      sl = Math.min(stopLine, lineOffset + nextOffset.line);
+
+      if (sl === stopLine) {
+        sc = Math.min(stopColumn, columnOffset + nextOffset.column);
+      } else if (sl < stopLine) {
+        sc = columnOffset + nextOffset.column;
+      }
+    }
+
+    addSection(
+      map,
+      mapUrl,
+      mappings,
+      sources,
+      sourcesContent,
+      names,
+      ignoreList,
+      lineOffset + offset.line,
+      columnOffset + offset.column,
+      sl,
+      sc,
+    );
+  }
+}
+
+function addSection(
+  input: SectionXInput['map'],
+  mapUrl: string | null | undefined,
+  mappings: SourceMapSegment[][],
+  sources: string[],
+  sourcesContent: (string | null)[],
+  names: string[],
+  ignoreList: number[],
+  lineOffset: number,
+  columnOffset: number,
+  stopLine: number,
+  stopColumn: number,
+) {
+  const parsed = parse(input);
+  if ('sections' in parsed) return recurse(...(arguments as unknown as Parameters<typeof recurse>));
+
+  const map = new TraceMap(parsed, mapUrl);
+  const sourcesOffset = sources.length;
+  const namesOffset = names.length;
+  const decoded = decodedMappings(map);
+  const { resolvedSources, sourcesContent: contents, ignoreList: ignores } = map;
+
+  append(sources, resolvedSources);
+  append(names, map.names);
+
+  if (contents) append(sourcesContent, contents);
+  else for (let i = 0; i < resolvedSources.length; i++) sourcesContent.push(null);
+
+  if (ignores) for (let i = 0; i < ignores.length; i++) ignoreList.push(ignores[i] + sourcesOffset);
+
+  for (let i = 0; i < decoded.length; i++) {
+    const lineI = lineOffset + i;
+
+    // We can only add so many lines before we step into the range that the next section's map
+    // controls. When we get to the last line, then we'll start checking the segments to see if
+    // they've crossed into the column range. But it may not have any columns that overstep, so we
+    // still need to check that we don't overstep lines, too.
+    if (lineI > stopLine) return;
+
+    // The out line may already exist in mappings (if we're continuing the line started by a
+    // previous section). Or, we may have jumped ahead several lines to start this section.
+    const out = getLine(mappings, lineI);
+    // On the 0th loop, the section's column offset shifts us forward. On all other lines (since the
+    // map can be multiple lines), it doesn't.
+    const cOffset = i === 0 ? columnOffset : 0;
+
+    const line = decoded[i];
+    for (let j = 0; j < line.length; j++) {
+      const seg = line[j];
+      const column = cOffset + seg[COLUMN];
+
+      // If this segment steps into the column range that the next section's map controls, we need
+      // to stop early.
+      if (lineI === stopLine && column >= stopColumn) return;
+
+      if (seg.length === 1) {
+        out.push([column]);
+        continue;
+      }
+
+      const sourcesIndex = sourcesOffset + seg[SOURCES_INDEX];
+      const sourceLine = seg[SOURCE_LINE];
+      const sourceColumn = seg[SOURCE_COLUMN];
+      out.push(
+        seg.length === 4
+          ? [column, sourcesIndex, sourceLine, sourceColumn]
+          : [column, sourcesIndex, sourceLine, sourceColumn, namesOffset + seg[NAMES_INDEX]],
+      );
+    }
+  }
+}
+
+function append<T>(arr: T[], other: T[]) {
+  for (let i = 0; i < other.length; i++) arr.push(other[i]);
+}
+
+function getLine<T>(arr: T[][], index: number): T[] {
+  for (let i = arr.length; i <= index; i++) arr[i] = [];
+  return arr[index];
+}