refactor(api): move isThenable to utils

ext · ext · commit e89ca3d3e939 · 2023-12-25T02:30:23.000+01:00
diff --git a/src/jest/utils/is-thenable.ts b/src/jest/utils/is-thenable.ts
@@ -1,3 +1,6 @@
-export function isThenable<T>(src: T | Promise<T>): src is Promise<T> {
-	return src && typeof src === "object" && typeof (src as any).then === "function";
+/**
+ * @internal
+ */
+export function isThenable<T>(value: T | Promise<T>): value is Promise<T> {
+	return value && typeof value === "object" && "then" in value && typeof value.then === "function";
 }
diff --git a/src/utils/index.ts b/src/utils/index.ts
@@ -1,5 +1,6 @@
 export { type CompatibilityOptions } from "./compatibility-check";
 export { computeHash } from "./compute-hash";
 export { interpolate } from "./interpolate";
+export { isThenable } from "./is-thenable";
 export { requireUncached } from "./require-uncached";
 export { ruleExists } from "./rule-exists";
diff --git a/src/utils/is-thenable.spec.ts b/src/utils/is-thenable.spec.ts
@@ -0,0 +1,13 @@
+import { isThenable } from "./is-thenable";
+
+it("should return true if given a promise", () => {
+	expect.assertions(1);
+	const value = Promise.resolve("foo");
+	expect(isThenable(value)).toBeTruthy();
+});
+
+it("should return false if given a primitive value", () => {
+	expect.assertions(1);
+	const value = "foo";
+	expect(isThenable(value)).toBeFalsy();
+});
diff --git a/src/utils/is-thenable.ts b/src/utils/is-thenable.ts
@@ -0,0 +1,8 @@
+/**
+ * Test if value is a Promise (thenable).
+ *
+ * @internal
+ */
+export function isThenable<T>(value: T | Promise<T>): value is Promise<T> {
+	return value && typeof value === "object" && "then" in value && typeof value.then === "function";
+}

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,6 @@`
`1`		`-export function isThenable<T>(src: T \| Promise<T>): src is Promise<T> {`
`2`		`- return src && typeof src === "object" && typeof (src as any).then === "function";`
	`1`	`+/**`
	`2`	`+ * @internal`
	`3`	`+ */`
	`4`	`+export function isThenable<T>(value: T \| Promise<T>): value is Promise<T> {`
	`5`	`+ return value && typeof value === "object" && "then" in value && typeof value.then === "function";`
`3`	`6`	`}`