From 50d1b53ec2c2d5095df265e90d6fac56dc46cbbf Mon Sep 17 00:00:00 2001
From: Francisco Giordano <frangio.1@gmail.com>
Date: Mon, 5 Oct 2020 12:57:20 -0300
Subject: [PATCH] fix: filter out undefined query parameters and headers (#209)

---
 src/merge.ts                            |  5 +++++
 src/util/remove-undefined-properties.ts |  8 +++++++
 test/endpoint.test.ts                   | 29 +++++++++++++++++++++++++
 3 files changed, 42 insertions(+)
 create mode 100644 src/util/remove-undefined-properties.ts

diff --git a/src/merge.ts b/src/merge.ts
index c2a0939f..bbbbf24a 100644
--- a/src/merge.ts
+++ b/src/merge.ts
@@ -2,6 +2,7 @@ import { EndpointDefaults, RequestParameters, Route } from "@octokit/types";
 
 import { lowercaseKeys } from "./util/lowercase-keys";
 import { mergeDeep } from "./util/merge-deep";
+import { removeUndefinedProperties } from "./util/remove-undefined-properties";
 
 export function merge(
   defaults: EndpointDefaults | null,
@@ -18,6 +19,10 @@ export function merge(
   // lowercase header names before merging with defaults to avoid duplicates
   options.headers = lowercaseKeys(options.headers);
 
+  // remove properties with undefined values before merging
+  removeUndefinedProperties(options);
+  removeUndefinedProperties(options.headers);
+
   const mergedOptions = mergeDeep(defaults || {}, options) as EndpointDefaults;
 
   // mediaType.previews arrays are merged, instead of overwritten
diff --git a/src/util/remove-undefined-properties.ts b/src/util/remove-undefined-properties.ts
new file mode 100644
index 00000000..45129250
--- /dev/null
+++ b/src/util/remove-undefined-properties.ts
@@ -0,0 +1,8 @@
+export function removeUndefinedProperties(obj: any): any {
+  for (const key in obj) {
+    if (obj[key] === undefined) {
+      delete obj[key];
+    }
+  }
+  return obj;
+}
diff --git a/test/endpoint.test.ts b/test/endpoint.test.ts
index 0c13ce3d..728b0922 100644
--- a/test/endpoint.test.ts
+++ b/test/endpoint.test.ts
@@ -427,4 +427,33 @@ describe("endpoint()", () => {
       },
     });
   });
+
+  it("Undefined query parameter", () => {
+    const options = endpoint({
+      method: "GET",
+      url: "/notifications",
+      before: undefined,
+    });
+
+    expect(options).toEqual({
+      method: "GET",
+      url: "https://api.github.com/notifications",
+      headers: {
+        accept: "application/vnd.github.v3+json",
+        "user-agent": userAgent,
+      },
+    });
+  });
+
+  it("Undefined header value", () => {
+    const options = endpoint({
+      method: "GET",
+      url: "/notifications",
+      headers: {
+        "if-modified-since": undefined,
+      },
+    });
+
+    expect(options).not.toHaveProperty("headers.if-modified-since");
+  });
 });