tf_code/packages/opencode/test/fixture/instance.ts

import { ConfigProvider, Layer, ManagedRuntime } from "effect";
import { InstanceContext } from "../../src/effect/instance-context";
import { Instance } from "../../src/project/instance";

/** ConfigProvider that enables the experimental file watcher. */
export const watcherConfigLayer = ConfigProvider.layer(
	ConfigProvider.fromUnknown({
		OPENCODE_EXPERIMENTAL_FILEWATCHER: "true",
		OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER: "false",
	}),
);

/**
 * Boot an Instance with the given service layers and run `body` with
 * the ManagedRuntime. Cleanup is automatic — the runtime is disposed
 * and Instance context is torn down when `body` completes.
 *
 * Layers may depend on InstanceContext (provided automatically).
 * Pass extra layers via `options.provide` (e.g. ConfigProvider.layer).
 */
export function withServices<S>(
	directory: string,
	layer: Layer.Layer<S, any, InstanceContext>,
	body: (rt: ManagedRuntime.ManagedRuntime<S, never>) => Promise<void>,
	options?: { provide?: Layer.Layer<never>[] },
) {
	return Instance.provide({
		directory,
		fn: async () => {
			const ctx = Layer.sync(InstanceContext, () =>
				InstanceContext.of({
					directory: Instance.directory,
					worktree: Instance.worktree,
					project: Instance.project,
				}),
			);
			let resolved: Layer.Layer<S> = Layer.fresh(layer).pipe(
				Layer.provide(ctx),
			) as any;
			if (options?.provide) {
				for (const l of options.provide) {
					resolved = resolved.pipe(Layer.provide(l)) as any;
				}
			}
			const rt = ManagedRuntime.make(resolved);
			try {
				await body(rt);
			} finally {
				await rt.dispose();
			}
		},
	});
}