modify shoreline mock to accept multiple user ids

No change to existing tests using it, but I'll need to be able to mock
multiple users to test the new invites system.

Part of BACK-2500

api/setup_test.go

@@ -1,6 +1,8 @@
 package api
 
 import (
+	"fmt"
+
 	commonClients "github.com/tidepool-org/go-common/clients"
 	"github.com/tidepool-org/go-common/clients/highwater"
 	"github.com/tidepool-org/go-common/clients/shoreline"
@@ -53,7 +55,7 @@ var (
 )
 
 // In an effort to mock shoreline so that we can return the token we wish
-type testingShorelineMock struct{ userid string }
+type testingShorelineMock struct{ userIDs []string }
 
 func (m *testingShorelineMock) CreateCustodialUserForClinic(clinicId string, userData shoreline.CustodialUserData, token string) (*shoreline.UserData, error) {
 	panic("Not Implemented")
@@ -63,27 +65,60 @@ func (m *testingShorelineMock) DeleteUserSessions(userID, token string) error {
 	panic("Not Implemented")
 }
 
-func newtestingShorelineMock(userid string) *testingShorelineMock {
-	return &testingShorelineMock{userid: userid}
+func newtestingShorelineMock(userIDs ...string) *testingShorelineMock {
+	return &testingShorelineMock{userIDs: userIDs}
 }
 
 func (m *testingShorelineMock) Start() error { return nil }
 func (m *testingShorelineMock) Close()       {}
-func (m *testingShorelineMock) Login(username, password string) (*shoreline.UserData, string, error) {
-	return &shoreline.UserData{UserID: m.userid, Emails: []string{m.userid + "@email.org"}, Username: m.userid + "@email.org"}, "", nil
+func (m *testingShorelineMock) Login(userID, password string) (*shoreline.UserData, string, error) {
+	for _, mockedUserID := range m.userIDs {
+		if mockedUserID == userID {
+			return m.mockUser(mockedUserID), "", nil
+		}
+	}
+	return nil, "", fmt.Errorf("userID not mocked: %q", userID)
 }
-func (m *testingShorelineMock) Signup(username, password, email string) (*shoreline.UserData, error) {
-	return &shoreline.UserData{UserID: m.userid, Emails: []string{m.userid + "@email.org"}, Username: m.userid + "@email.org"}, nil
+
+func (m *testingShorelineMock) mockUser(userID string) *shoreline.UserData {
+	return &shoreline.UserData{
+		UserID:   userID,
+		Emails:   []string{userID + "@email.org"},
+		Username: userID + "@email.org",
+	}
+}
+
+func (m *testingShorelineMock) Signup(userID, password, email string) (*shoreline.UserData, error) {
+	for _, mockedUserID := range m.userIDs {
+		if mockedUserID == userID {
+			return m.mockUser(userID), nil
+		}
+	}
+	return nil, fmt.Errorf("userID not mocked: %q", userID)
 }
+
 func (m *testingShorelineMock) TokenProvide() string { return testing_token }
+
 func (m *testingShorelineMock) GetUser(userID, token string) (*shoreline.UserData, error) {
-	return &shoreline.UserData{UserID: m.userid, Emails: []string{m.userid + "@email.org"}, Username: m.userid + "@email.org"}, nil
+	for _, mockedUserID := range m.userIDs {
+		if mockedUserID == userID {
+			return m.mockUser(userID), nil
+		}
+	}
+	return nil, fmt.Errorf("userID not mocked: %q", userID)
 }
+
 func (m *testingShorelineMock) UpdateUser(userID string, userUpdate shoreline.UserUpdate, token string) error {
 	return nil
 }
+
 func (m *testingShorelineMock) CheckToken(token string) *shoreline.TokenData {
-	return &shoreline.TokenData{UserID: m.userid, IsServer: false}
+	for _, mockedUserID := range m.userIDs {
+		if mockedUserID == token || (token == testing_token_uid1 && mockedUserID == testing_uid1) {
+			return &shoreline.TokenData{UserID: mockedUserID, IsServer: false}
+		}
+	}
+	return nil
 }
 
 type (