2 files changed, 46 insertions, 0 deletions

diff --git a/packages/kernel/src/host/host.test.ts b/packages/kernel/src/host/host.test.ts
index 669d093..0067091 100644
--- a/packages/kernel/src/host/host.test.ts
+++ b/packages/kernel/src/host/host.test.ts
@@ -617,6 +617,49 @@ describe("createHost", () => {
 			expect(received).toEqual(["hello"]);
 		});
 
+		it("emit dispatches to handlers registered via on", async () => {
+			const hook = defineEventHook<string>("test/emit-dispatch");
+			const received: string[] = [];
+
+			const ext = createExtension("emit-ext", {
+				activate: (host) => {
+					host.on(hook, (payload) => {
+						received.push(payload);
+					});
+				},
+			});
+
+			const host = createHost([ext], deps);
+			await host.activate();
+
+			const api = host.getHostAPI();
+			api.emit(hook, "world");
+			expect(received).toEqual(["world"]);
+		});
+
+		it("emit isolates a throwing handler (does not propagate)", async () => {
+			const hook = defineEventHook<string>("test/emit-isolation");
+			const received: string[] = [];
+
+			const ext = createExtension("emit-isolation-ext", {
+				activate: (host) => {
+					host.on(hook, () => {
+						throw new Error("handler boom");
+					});
+					host.on(hook, (payload) => {
+						received.push(payload);
+					});
+				},
+			});
+
+			const host = createHost([ext], deps);
+			await host.activate();
+
+			const api = host.getHostAPI();
+			expect(() => api.emit(hook, "safe")).not.toThrow();
+			expect(received).toEqual(["safe"]);
+		});
+
 		it("applyFilters threads a value through registered filters in order", async () => {
 			const hook = defineFilter<string>("test/text-transform");
 
diff --git a/packages/kernel/src/host/host.ts b/packages/kernel/src/host/host.ts
index a6396a9..2a262be 100644
--- a/packages/kernel/src/host/host.ts
+++ b/packages/kernel/src/host/host.ts
@@ -122,6 +122,9 @@ export function createHost(extensions: readonly Extension[], deps: HostDeps): Ho
 			on<TPayload>(hook: EventHookDescriptor<TPayload>, handler: EventHandler<TPayload>) {
 				return deps.bus.on(hook, handler);
 			},
+			emit<TPayload>(hook: EventHookDescriptor<TPayload>, payload: TPayload) {
+				deps.bus.emit(hook, payload);
+			},
 			addFilter<TValue>(hook: FilterDescriptor<TValue>, fn: FilterHandler<TValue>) {
 				return deps.bus.addFilter(hook, fn);
 			},