Don't redact null or undefined

src/utils/redact.test.ts

@@ -34,3 +34,25 @@ test("no redaction of unrelated keys", () => {
     bar: "foo",
   });
 });
+
+test("no redaction of missing keys", () => {
+  expect(
+    redact({ foo: "bar" } as { foo: string; bar: string | undefined }, "bar"),
+  ).to.deep.equal({
+    foo: "bar",
+  });
+});
+
+test("no redaction of null values", () => {
+  expect(redact({ foo: "bar", bar: null }, "bar")).to.deep.equal({
+    foo: "bar",
+    bar: null,
+  });
+});
+
+test("no redaction of undefined values", () => {
+  expect(redact({ foo: "bar", bar: undefined }, "bar")).to.deep.equal({
+    foo: "bar",
+    bar: undefined,
+  });
+});

src/utils/redact.ts

@@ -12,6 +12,14 @@ Please see LICENSE in the repository root for full details.
  * @param keys Keys to be redacted in the object
  * @returns A new object with the specified properties redacted
  */
-export function redact<T extends object>(obj: T, ...keys: (keyof T)[]): T {
-  return { ...obj, ...Object.fromEntries(keys.map((k) => [k, "<redacted>"])) };
+export function redact<T extends object>(
+  obj: T,
+  ...keys: (keyof T)[]
+): Record<keyof T, unknown> {
+  const result: Record<keyof T, unknown> = { ...obj };
+  for (const key of keys)
+    if (key in result && result[key] != null) {
+      result[key] = "<redacted>";
+    }
+  return result;
 }