refactor: update-tool should support migrations without target version

Updates the update-tool to support migrations without a target version.
Consider the MDC update script relying on the update-tool but it being
always manually invoked. In those cases there is no actual target
version.

Author: devversion

src/cdk/schematics/ng-update/upgrade-data.ts

@@ -71,6 +71,10 @@ export function getVersionUpgradeData<
   T extends keyof UpgradeData,
   U = ValueOfChanges<UpgradeData[T]>,
 >(migration: Migration<UpgradeData>, dataName: T): U[] {
+  if (migration.targetVersion === null) {
+    return [];
+  }
+
   // Note that below we need to cast to `unknown` first TS doesn't infer the type of T correctly.
   return getChangesForTarget<U>(
     migration.targetVersion,

src/cdk/schematics/update-tool/index.ts

@@ -45,14 +45,15 @@ export class UpdateProject<Context> {
   /**
    * Migrates the project to the specified target version.
    * @param migrationTypes Migrations that should be run.
-   * @param target Version the project should be updated to.
+   * @param target Version the project should be updated to. Can be `null` if the set of
+   *   specified migrations runs regardless of a target version.
    * @param data Upgrade data that is passed to all migration rules.
    * @param additionalStylesheetPaths Additional stylesheets that should be migrated, if not
    *   referenced in an Angular component. This is helpful for global stylesheets in a project.
    */
   migrate<Data>(
     migrationTypes: MigrationCtor<Data, Context>[],
-    target: TargetVersion,
+    target: TargetVersion | null,
     data: Data,
     additionalStylesheetPaths?: string[],
   ): {hasFailures: boolean} {
@@ -157,7 +158,7 @@ export class UpdateProject<Context> {
    */
   private _createMigrations<Data>(
     types: MigrationCtor<Data, Context>[],
-    target: TargetVersion,
+    target: TargetVersion | null,
     data: Data,
   ): Migration<Data, Context>[] {
     const result: Migration<Data, Context>[] = [];

src/cdk/schematics/update-tool/migration.ts

@@ -41,8 +41,11 @@ export abstract class Migration<Data, Context = any> {
     public program: ts.Program,
     /** TypeChecker instance for the analysis program. */
     public typeChecker: ts.TypeChecker,
-    /** Version for which the migration rule should run. */
-    public targetVersion: TargetVersion,
+    /**
+     * Version for which the migration rule should run. Null if the migration
+     * is invoked manually.
+     */
+    public targetVersion: TargetVersion | null,
     /** Context data for the migration. */
     public context: Context,
     /** Upgrade data passed to the migration. */

src/material/schematics/ng-update/migrations/hammer-gestures-v9/hammer-gestures-migration.ts

@@ -990,7 +990,7 @@ export class HammerGesturesMigration extends DevkitMigration<null> {
   }
 
   /** Gets whether the migration is allowed to run for specified target version. */
-  private static _isAllowedVersion(target: TargetVersion) {
+  private static _isAllowedVersion(target: TargetVersion | null) {
     // This migration is only allowed to run for v9 or v10 target versions.
     return target === TargetVersion.V9 || target === TargetVersion.V10;
   }