diff --git a/packages/core-api/src/lib/versionedValues.test.ts b/packages/core-api/src/lib/versionedValues.test.ts new file mode 100644 index 0000000000..6ba7db4970 --- /dev/null +++ b/packages/core-api/src/lib/versionedValues.test.ts @@ -0,0 +1,40 @@ +/* + * Copyright 2021 Spotify AB + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +import { createVersionedValueMap } from './versionedValues'; + +describe('createVersionedValueMap', () => { + it('should be empty', () => { + const map = createVersionedValueMap({}); + + // @ts-expect-error + expect(map.atVersion(1 as any)).toBe(undefined); + }); + + it('should access values by version', () => { + const map = createVersionedValueMap({ 1: 'v1', 2: 'v2' }); + + expect(map.atVersion(1)).toBe('v1'); + expect(map.atVersion(2)).toBe('v2'); + + // @ts-expect-error + expect(map.atVersion(0)).toBe(undefined); + // @ts-expect-error + expect(map.atVersion(NaN)).toBe(undefined); + // @ts-expect-error + expect(map.atVersion(Infinity)).toBe(undefined); + }); +}); diff --git a/packages/core-api/src/lib/versionedValues.ts b/packages/core-api/src/lib/versionedValues.ts new file mode 100644 index 0000000000..88e4e90084 --- /dev/null +++ b/packages/core-api/src/lib/versionedValues.ts @@ -0,0 +1,40 @@ +/* + * Copyright 2021 Spotify AB + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/** + * The versioned value interface is a container for a set of values that + * can be looked up by version. It is intended to be used as a container + * for values that can be versioned independently of package versions. + */ +export type VersionedValue = { + atVersion( + version: Version, + ): Versions[Version] | undefined; +}; + +/** + * Creates a container for a map of versioned values that implements VersionedValue. + */ +export function createVersionedValueMap< + Versions extends { [version: number]: any } +>(versions: Versions): VersionedValue { + Object.freeze(versions); + return { + atVersion(version) { + return versions[version]; + }, + }; +}