Properly type preliminaryStepDefinitions

This is some TS shenanigans in prepration of further work.

Author: badeball

lib/browser-runtime.ts

@@ -83,7 +83,7 @@ type Node = ReturnType<typeof parse>;
 type TestStepIds = Map<string, Map<string, string>>;
 
 interface CompositionContext {
-  registry: Registry;
+  registry: Registry<Mocha.Context, unknown[]>;
   newId: messages.IdGenerator.NewId;
   gherkinDocument: messages.GherkinDocument;
   astIdsMap: ReturnType<typeof createAstIdMap>;
@@ -1176,7 +1176,7 @@ function afterHandler(this: Mocha.Context, context: CompositionContext) {
 }
 
 export default function createTests(
-  registry: Registry,
+  registry: Registry<Mocha.Context, unknown[]>,
   seed: number,
   source: string,
   gherkinDocument: messages.GherkinDocument,

lib/entrypoint-browser.ts

@@ -48,7 +48,7 @@ function defineStep<T extends unknown[], C extends Mocha.Context>(
   description: string | RegExp,
   implementation: IStepDefinitionBody<T, C>,
 ) {
-  getRegistry().defineStep(description, implementation);
+  getRegistry<C, T>().defineStep(description, implementation);
 }
 
 function runStepDefinition(

lib/registry.ts

@@ -88,16 +88,16 @@ function parseMaybeTags(tags?: string): Node {
   return tags ? parse(tags) : noopNode;
 }
 
-export class Registry {
+export class Registry<C extends Mocha.Context, T extends unknown[]> {
   public parameterTypeRegistry: ParameterTypeRegistry;
 
   private preliminaryStepDefinitions: {
     description: string | RegExp;
-    implementation: () => void;
+    implementation: IStepDefinitionBody<T, C>;
     position?: Position;
   }[] = [];
 
-  public stepDefinitions: IStepDefinition<unknown[], Mocha.Context>[] = [];
+  public stepDefinitions: IStepDefinition<T, C>[] = [];
 
   private preliminaryHooks: Omit<ICaseHook, "id">[] = [];
 
@@ -151,7 +151,10 @@ export class Registry {
     }
   }
 
-  public defineStep(description: string | RegExp, implementation: () => void) {
+  public defineStep(
+    description: string | RegExp,
+    implementation: IStepDefinitionBody<T, C>,
+  ) {
     if (typeof description !== "string" && !(description instanceof RegExp)) {
       throw new Error("Unexpected argument for step definition");
     }
@@ -281,7 +284,7 @@ export class Registry {
   }
 
   public runStepDefinition(
-    world: Mocha.Context,
+    world: C,
     text: string,
     dryRun: boolean,
     argument?: DataTable | string,
@@ -290,7 +293,7 @@ export class Registry {
 
     const args = stepDefinition.expression
       .match(text)!
-      .map((match) => match.getValue(world));
+      .map((match) => match.getValue(world)) as T;
 
     if (argument) {
       args.push(argument);
@@ -375,26 +378,31 @@ export class Registry {
 const globalPropertyName =
   "__cypress_cucumber_preprocessor_registry_dont_use_this";
 
-export function withRegistry(
+export function withRegistry<C extends Mocha.Context, T extends unknown[]>(
   experimentalSourceMap: boolean,
   fn: () => void,
-): Registry {
-  const registry = new Registry(experimentalSourceMap);
+): Registry<C, T> {
+  const registry = new Registry<C, T>(experimentalSourceMap);
   assignRegistry(registry);
   fn();
   freeRegistry();
   return registry;
 }
 
-export function assignRegistry(registry: Registry) {
+export function assignRegistry<C extends Mocha.Context, T extends unknown[]>(
+  registry: Registry<C, T>,
+) {
   globalThis[globalPropertyName] = registry;
 }
 
 export function freeRegistry() {
   delete globalThis[globalPropertyName];
 }
 
-export function getRegistry(): Registry {
+export function getRegistry<
+  C extends Mocha.Context,
+  T extends unknown[],
+>(): Registry<C, T> {
   return assertAndReturn(
     globalThis[globalPropertyName],
     "Expected to find a global registry (this usually means you are trying to define steps or hooks in support/e2e.js, which is not supported)",