chore: import upstream snapshot with attribution

examples/integrations/_parity/lib/diff.ts

@@ -0,0 +1,47 @@
+import { createHash } from "node:crypto";
+import { readFileSync, statSync } from "node:fs";
+
+export function sha256(buf: Buffer | string): string {
+  return createHash("sha256").update(buf).digest("hex");
+}
+
+export function fileSha256(path: string): string {
+  return sha256(readFileSync(path));
+}
+
+export function fileExists(path: string): boolean {
+  try {
+    statSync(path);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+export function getByPath(obj: unknown, path: string): unknown {
+  const parts = path.split(".");
+  let cur: unknown = obj;
+  for (const part of parts) {
+    if (cur == null || typeof cur !== "object") return undefined;
+    cur = (cur as Record<string, unknown>)[part];
+  }
+  return cur;
+}
+
+export function setByPath(
+  obj: Record<string, unknown>,
+  path: string,
+  value: unknown,
+): void {
+  const parts = path.split(".");
+  let cur: Record<string, unknown> = obj;
+  for (let i = 0; i < parts.length - 1; i++) {
+    const key = parts[i]!;
+    const next = cur[key];
+    if (next == null || typeof next !== "object" || Array.isArray(next)) {
+      cur[key] = {};
+    }
+    cur = cur[key] as Record<string, unknown>;
+  }
+  cur[parts[parts.length - 1]!] = value;
+}