From 1ec0968a8f25daca40092f8533421584ebc7df02 Mon Sep 17 00:00:00 2001
From: Jeff Yates <jeff@khanacademy.org>
Date: Thu, 14 Jul 2022 12:22:05 -0500
Subject: [PATCH] [fixkeystypes] Improve keys typing (#321)
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## Summary:
I found that the typing was not helpful so I added a test case for the issue I experienced and then tweaked the function definition so that all the flow tests passed.

No functional change here, purely types.

Issue: FEI-4655

## Test plan:
`yarn flow`

Author: somewhatabstract

Reviewers: jeresig, benchristel, somewhatabstract

Required Reviewers:

Approved By: jeresig

Checks: ✅ Test (macOS-latest, 16.x), ✅ codecov/project, ✅ CodeQL, ✅ Lint, flow, and coverage check (ubuntu-latest, 16.x), ✅ Prime node_modules cache for primary configuration (ubuntu-latest, 16.x), ✅ gerald, ✅ Analyze (javascript), ⏭  dependabot

Pull Request URL: https://github.com/Khan/wonder-stuff/pull/321
---
 .changeset/polite-snails-grab.md                      |  5 +++++
 .../wonder-stuff-core/src/__tests__/keys.flowtest.js  | 11 +++++++++++
 packages/wonder-stuff-core/src/keys.js                |  2 +-
 3 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/polite-snails-grab.md

diff --git a/.changeset/polite-snails-grab.md b/.changeset/polite-snails-grab.md
new file mode 100644
index 00000000..4bffe55c
--- /dev/null
+++ b/.changeset/polite-snails-grab.md
@@ -0,0 +1,5 @@
+---
+"@khanacademy/wonder-stuff-core": patch
+---
+
+Update types for `keys` so that it works with a wider variety of object shapes
diff --git a/packages/wonder-stuff-core/src/__tests__/keys.flowtest.js b/packages/wonder-stuff-core/src/__tests__/keys.flowtest.js
index 9833bc51..accb40f6 100644
--- a/packages/wonder-stuff-core/src/__tests__/keys.flowtest.js
+++ b/packages/wonder-stuff-core/src/__tests__/keys.flowtest.js
@@ -32,3 +32,14 @@ import {keys} from "../keys.js";
     const keys2bad = keys(obj2);
     const __: "a" = keys2bad[0];
 }
+
+{
+    // should work with more specific object types
+    const obj3: {|[string]: string|} = {
+        a: "1",
+        b: "2",
+    };
+
+    // This should not be erroring.
+    const _ = keys(obj3);
+}
diff --git a/packages/wonder-stuff-core/src/keys.js b/packages/wonder-stuff-core/src/keys.js
index e2b01164..201f616c 100644
--- a/packages/wonder-stuff-core/src/keys.js
+++ b/packages/wonder-stuff-core/src/keys.js
@@ -6,6 +6,6 @@
  * to be returned.
  * @returns {Array<$Keys<O>>} An array of the enumerable keys of an object.
  */
-export function keys<O: {[string]: mixed}>(obj: O): Array<$Keys<O>> {
+export function keys<O: {[string]: mixed}>(obj: $ReadOnly<O>): Array<$Keys<O>> {
     return Object.keys(obj);
 }