Accept "undefined" in place of userAgent string

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## [4.3.0](https://github.com/omrilotan/isbot/compare/v4.2.0...v4.3.0)
+
+- Accept `undefined` in place of user agent string to allow headers property to be used "as is" (`request.headers["user-agent"]`)
+
 ## [4.2.0](https://github.com/omrilotan/isbot/compare/v4.1.1...v4.2.0)
 
 - Accept `null` in place of user agent string to allow header value to be used "as is" (`request.headers.get("user-agent")`)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "isbot",
-  "version": "4.2.0",
+  "version": "4.3.0",
   "description": "🤖 Recognise bots/crawlers/spiders using the user agent string.",
   "keywords": [
     "bot",

src/index.ts

@@ -16,14 +16,14 @@ export const list: string[] = patternsList;
 /**
  * Check if the given user agent includes a bot pattern.
  */
-export const isbot = (userAgent: string | null): boolean =>
+export const isbot = (userAgent?: string | null): boolean =>
 	Boolean(userAgent) && pattern.test(userAgent);
 
 /**
  * Create a custom isbot function with a custom pattern.
  */
 export const createIsbot =
-	(customPattern: RegExp): ((userAgent: string | null) => boolean) =>
+	(customPattern: RegExp): ((userAgent?: string | null) => boolean) =>
 	(userAgent: string): boolean =>
 		Boolean(userAgent) && customPattern.test(userAgent);
 
@@ -41,29 +41,29 @@ export const createIsbotFromList = (
 /**
  * Find the first part of the user agent that matches a bot pattern.
  */
-export const isbotMatch = (userAgent: string | null): string | null =>
+export const isbotMatch = (userAgent?: string | null): string | null =>
 	userAgent?.match(pattern)?.[0] ?? null;
 
 /**
  * Find all parts of the user agent that match a bot pattern.
  */
-export const isbotMatches = (userAgent: string | null): string[] =>
+export const isbotMatches = (userAgent?: string | null): string[] =>
 	list
 		.map((part) => userAgent?.match(new RegExp(part, "i"))?.[0])
 		.filter(Boolean);
 
 /**
  * Find the first bot patterns that match the given user agent.
  */
-export const isbotPattern = (userAgent: string | null): string | null =>
+export const isbotPattern = (userAgent?: string | null): string | null =>
 	userAgent
 		? list.find((pattern) => new RegExp(pattern, "i").test(userAgent)) ?? null
 		: null;
 
 /**
  * Find all bot patterns that match the given user agent.
  */
-export const isbotPatterns = (userAgent: string | null): string[] =>
+export const isbotPatterns = (userAgent?: string | null): string[] =>
 	userAgent
 		? list.filter((pattern) => new RegExp(pattern, "i").test(userAgent))
 		: [];

tests/spec/test.ts

@@ -67,12 +67,14 @@ describe("isbot", () => {
 			expect(isbot(ua)).toBe(true);
 			expect(isbot2(ua)).toBe(false);
 		});
-		test("all functions can accept null", () => {
-			expect(isbot(null)).toBe(false);
-			expect(isbotMatch(null)).toBe(null);
-			expect(isbotMatches(null)).toEqual([]);
-			expect(isbotPattern(null)).toBe(null);
-			expect(isbotPatterns(null)).toEqual([]);
+		test.each(
+			[null, undefined, ""]
+		)("all functions can accept %p", (value: string | null | undefined) => {
+			expect(isbot(value)).toBe(false);
+			expect(isbotMatch(value)).toBe(null);
+			expect(isbotMatches(value)).toEqual([]);
+			expect(isbotPattern(value)).toBe(null);
+			expect(isbotPatterns(value)).toEqual([]);
 		});
 	});