feat: export getAdapter function (#5324)

test/module/typings/esm/index.ts

@@ -16,6 +16,7 @@ import axios, {
   ParamsSerializerOptions,
   toFormData,
   formToJSON,
+  getAdapter,
   all,
   isCancel,
   isAxiosError,
@@ -570,6 +571,33 @@ axios.get('/user', {
   adapter: ['xhr', 'http']
 });
 
+
+{
+  // getAdapter
+  
+  getAdapter(axios.create().defaults.adapter);
+  getAdapter(undefined);
+  getAdapter([]);
+  getAdapter(['xhr']);
+  getAdapter([adapter]);
+  getAdapter(['xhr', 'http']);
+  getAdapter([adapter, 'xhr']);
+  getAdapter([adapter, adapter]);
+  getAdapter('xhr');
+  getAdapter(adapter);
+  const _: AxiosAdapter = getAdapter('xhr');
+  const __: AxiosAdapter = getAdapter(['xhr']);
+
+  // @ts-expect-error
+  getAdapter();
+  // @ts-expect-error
+  getAdapter(123);
+  // @ts-expect-error
+  getAdapter([123]);
+  // @ts-expect-error
+  getAdapter('xhr', 'http');
+}
+
 // AxiosHeaders
 
 // iterator

test/specs/api.spec.js

@@ -54,6 +54,10 @@ describe('static api', function () {
   it('should have mergeConfig properties', function () {
     expect(typeof axios.mergeConfig).toEqual('function');
   });
+
+  it('should have getAdapter properties', function () {
+    expect(typeof axios.getAdapter).toEqual('function');
+  });
 });
 
 describe('instance api', function () {

test/specs/instance.spec.js

@@ -24,6 +24,7 @@ describe('instance', function () {
         'getUri',
         'isAxiosError',
         'mergeConfig',
+        'getAdapter',
         'VERSION',
         'default',
         'toFormData',