Add type parameter for key to createContext()

justinfagnani · justinfagnani · commit 5d50e8a04908 · 2023-02-01T12:24:31.000-08:00
diff --git a/.changeset/happy-apricots-pay.md b/.changeset/happy-apricots-pay.md
@@ -0,0 +1,5 @@
+---
+'@lit-labs/context': patch
+---
+
+Add type parameter for key to createContext()
diff --git a/packages/labs/context/src/lib/create-context.ts b/packages/labs/context/src/lib/create-context.ts
@@ -49,8 +49,8 @@ export type ContextType<Key extends Context<unknown, unknown>> =
  *
  * @param key a context key value
  * @template ValueType the type of value that can be provided by this context.
- * @returns the context key value with the correct type
+ * @returns the context key value cast to `Context<K, ValueType>`
  */
-export function createContext<ValueType>(key: unknown) {
-  return key as Context<typeof key, ValueType>;
+export function createContext<ValueType, K = unknown>(key: K) {
+  return key as Context<K, ValueType>;
 }

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +'@lit-labs/context': patch
 +---
++
 +Add type parameter for key to createContext()
Original file line number	Diff line number	Diff line change
`@@ -49,8 +49,8 @@ export type ContextType<Key extends Context<unknown, unknown>> =`
`49`	`49`	`*`
`50`	`50`	`* @param key a context key value`
`51`	`51`	`* @template ValueType the type of value that can be provided by this context.`
`52`		`- * @returns the context key value with the correct type`
	`52`	+ * @returns the context key value cast to `Context<K, ValueType>`
`53`	`53`	`*/`
`54`		`-export function createContext<ValueType>(key: unknown) {`
`55`		`- return key as Context<typeof key, ValueType>;`
	`54`	`+export function createContext<ValueType, K = unknown>(key: K) {`
	`55`	`+ return key as Context<K, ValueType>;`
`56`	`56`	`}`