Function parseUnifiedPatch

lib/patch.ts:24–113

(text: string)

}

export function parseUnifiedPatch(text: string): SplitDiffFile[] | null {
  const files: SplitDiffFile[] = [];
  let current: SplitDiffFile | null = null;
  let pendingOldPath: string | undefined;
  let oldLineNo = 0;
  let newLineNo = 0;
  let removed: PendingChangeLine[] = [];
  let added: PendingChangeLine[] = [];

  const emptyCell = (): SplitDiffCell => ({ lineNo: null, text: "", type: "empty" });
  const flushChanges = () => {
    if (!current) {
      removed = [];
      added = [];
      return;
    }
    const count = Math.max(removed.length, added.length);
    for (let i = 0; i < count; i++) {
      const left = removed[i]
        ? { lineNo: removed[i].lineNo, text: removed[i].text, type: "removed" as const }
        : emptyCell();
      const right = added[i]
        ? { lineNo: added[i].lineNo, text: added[i].text, type: "added" as const }
        : emptyCell();
      current.rows.push({ type: "line", left, right });
    }
    removed = [];
    added = [];
  };

  for (const line of text.split(/\r?\n/)) {
    if (line.startsWith("--- ")) {
      flushChanges();
      pendingOldPath = cleanPatchPath(line.slice(4));
      continue;
    }

    if (line.startsWith("+++ ")) {
      flushChanges();
      current = { oldPath: pendingOldPath, newPath: cleanPatchPath(line.slice(4)), rows: [] };
      files.push(current);
      continue;
    }

    const hunk = line.match(/^@@ -(\d+)(?:,\d+)? \+(\d+)(?:,\d+)? @@/);
    if (hunk) {
      if (!current) {
        current = { rows: [] };
        files.push(current);
      }
      flushChanges();
      oldLineNo = Number(hunk[1]);
      newLineNo = Number(hunk[2]);
      current.rows.push({ type: "hunk", text: line });
      continue;
    }

    if (!current) continue;