Rework the SearchHeadlessProvider to be a pass-through.

Per Product's request, the `SearchHeadlessProvider` is now a mere
pass-through to the `SearchHeadlessContext.Provider`. Users will
need to create and initialize a `Headless` instance themselves.

The `acquireSessionId` utility will be moved to either the Component
Library or Headless, TBD. The Jest test that was added ensures the
`Provider` does not touch anything in the `Headless` instance.

TEST=auto

Ran all unit tests.

src/SearchHeadlessProvider.tsx

@@ -1,33 +1,14 @@
 import { PropsWithChildren } from 'react';
-import { provideHeadless, SearchHeadless, HeadlessConfig } from '@yext/search-headless';
+import { SearchHeadless } from '@yext/search-headless';
 import { SearchHeadlessContext } from './SearchHeadlessContext';
-import acquireSessionId from './utils/acquireSessionId';
-import packageJson from '../package.json';
 
-const { version } = packageJson;
-
-type Props = HeadlessConfig & {
-  verticalKey?: string,
-  sessionTrackingEnabled?: boolean
-};
+type Props = { searcher: SearchHeadless };
 
 export function SearchHeadlessProvider(props: PropsWithChildren<Props>): JSX.Element {
-  const { children, verticalKey, sessionTrackingEnabled=true, ...searchConfig } = props;
-  const additionalHttpHeaders = {
-    'Client-SDK': {
-      ANSWERS_HEADLESS_REACT: version
-    }
-  };
-  const search: SearchHeadless = provideHeadless(searchConfig, additionalHttpHeaders);
+  const { children, searcher } = props;
 
-  verticalKey && search.setVertical(verticalKey);
-  search.setSessionTrackingEnabled(sessionTrackingEnabled);
-  if (sessionTrackingEnabled) {
-    const sessionId = acquireSessionId();
-    sessionId && search.setSessionId(sessionId);
-  }
   return (
-    <SearchHeadlessContext.Provider value={search}>
+    <SearchHeadlessContext.Provider value={searcher}>
       {children}
     </SearchHeadlessContext.Provider>
   );

tests/SearchHeadlessProvider.test.tsx

@@ -1,23 +1,19 @@
-import { SearchHeadlessProvider, SandboxEndpoints } from '../src';
+import { SearchHeadlessProvider } from '../src';
 import { render } from '@testing-library/react';
-import { provideHeadless } from '@yext/search-headless';
+import { provideHeadless, SearchHeadless } from '@yext/search-headless';
 
 jest.mock('@yext/search-headless', () => ({
-  provideHeadless: jest.fn(() => ({
-    setSessionTrackingEnabled: jest.fn(),
-    setSessionId: jest.fn()
-  }))
+  provideHeadless: jest.fn(() => { return {}; })
 }));
 
-it('correctly passes through a search config with sandbox endpoints', () => {
+it('does not change anything about the supplied Headless instance', () => {
   const config = {
     apiKey: '<apiKey>',
     experienceKey: '<experienceKey>',
-    locale: 'en',
-    endpoints: SandboxEndpoints
+    locale: 'en'
   };
+  const searcher: SearchHeadless = provideHeadless(config);
 
-  render(<SearchHeadlessProvider {...config}/>);
-  expect(provideHeadless).toHaveBeenCalledTimes(1);
-  expect(provideHeadless).toHaveBeenCalledWith(config, expect.anything());
+  expect(
+    () => render(<SearchHeadlessProvider searcher={searcher}></SearchHeadlessProvider>)).not.toThrowError();
 });