Function getNextVersion

scripts/changes/changes.ts:22–36

* Calculates the next version based on current version, bump type, and changes config.

(currentVersion: string, bumpType: BumpType)

 * Calculates the next version based on current version, bump type, and changes config.
 */
function getNextVersion(currentVersion: string, bumpType: BumpType): string {
  if (bumpType === "unstable") {
    throw new Error(
      "`unstable` bump type should be normalized to a semver bump before calling `getNextVersion`",
    );
  }
  // Normal stable release
  let nextVersion = semver.inc(currentVersion, bumpType as semver.ReleaseType);
  if (nextVersion == null) {
    throw new Error(
      `Invalid version increment: ${currentVersion} + ${bumpType}`,
    );
  }
  return nextVersion;
}

interface ChangeFile {
  file: string;