Как тестируют в Google - страница 35



deps=[

"path/to/httpqueryparams",

"other_http_server_stuff",

":addurl", # Link against the addurl library above.

])

Разработчик снова запускает средства сборки, исправляет ошибки компиляции и компоновщика в addurl_frontend.h и addurl_frontend.cc, пока все не будет собираться и компоноваться без предупреждений или ошибок. На этой стадии пора писать юнит-тесты для AddUrlFrontend. Они пишутся в новом файле addurl_frontend_test.cc. Тест определяет имитацию для бэкенд-системы AddUrlService и использует конструктор AddUrlFrontend для внедрения этой имитации во время тестирования. При таком подходе разработчик может внедрять ожидания и ошибки в поток операций AddUrlFrontend без изменения кода AddUrlFrontend.

File: depot/addurl/addurl_frontend_test.cc

#include "addurl/addurl.pb.h"

#include "addurl/addurl_frontend.h"


// See http://code.google.com/p/googletest/

#include "path/to/googletest.h"


// Defines a fake AddUrlService, which will be injected by

// the AddUrlFrontendTest test fixture into AddUrlFrontend

// instances under test.


class FakeAddUrlService : public AddUrlService {

public:

 FakeAddUrlService()

: has_request_expectations_(false),

error_code_(0) {

}


// Allows tests to set expectations on requests.

void set_expected_url(const string& url) {

expected_url_ = url;

has_request_expectations_ = true;

}


void set_expected_comment(const string& comment) {

expected_comment_ = comment;

has_request_expectations_ = true;

}


// Allows for  injection of errors by tests.


void set_error_code(int error_code) {

error_code_ = error_code;

}

void set_error_details(const string& error_details) {

error_details_ = error_details;

}


// Overrides of the AddUrlService::AddUrl method generated from

// service definition in addurl.proto by the Protocol Buffer

// compiler.


virtual void AddUrl(RPC* rpc,

const AddUrlRequest* request,

AddUrlReply* reply) {


// Enforce expectations on request (if present).


if (has_request_expectations_) {

EXPECT_EQ(expected_url_, request->url());

EXPECT_EQ(expected_comment_, request->comment());

}


// Inject errors specified in the set_* methods above if present.


if (error_code_ != 0 || !error_details_.empty()) {

reply->set_error_code(error_code_);

reply->set_error_details(error_details_);

}

}


private:


 // Expected request information.

 // Clients set using set_expected_* methods.


 string expected_url_;

 string expected_comment_;

 bool has_request_expectations_;


 // Injected error information.

 // Clients set using set_* methods above.


 int error_code_;

 string error_details_;

};


// The test fixture for AddUrlFrontend. It is code shared by the

// TEST_F test definitions below. For every test using this

// fixture, the fixture will create a FakeAddUrlService, an

// AddUrlFrontend, and inject the FakeAddUrlService into that

// AddUrlFrontend. Tests will have access to both of these

// objects at runtime.

class AddurlFrontendTest : public ::testing::Test {


// Runs before every test method is executed.


 virtual void SetUp() {


// Create a FakeAddUrlService for  injection.


fake_add_url_service_.reset(new FakeAddUrlService);


// Create an AddUrlFrontend and inject our FakeAddUrlService

// into it.


add_url_frontend_.reset(

new AddUrlFrontend(fake_add_url_service_.get()));

}

 scoped_ptr fake_add_url_service_;

 scoped_ptr add_url_frontend_;

};


// Test that AddurlFrontendTest::SetUp works.