Fix MR Selection, Go Code Refactor (#358)

refactor: Refactors the Go codebase into a more modular and idiomatic approach
fix: require selection of specific MR when there are multiple targets for a given source branch
feat: Allows for the passing of Gitlab's filter options when choosing an MR, improves MR selection
feat: API to choose an MR from a list based on the provided username's involvement as an assignee/reviewer/author

This is a #MINOR release

cmd/app/comment_test.go

@@ -0,0 +1,124 @@
+package app
+
+import (
+	"net/http"
+	"testing"
+
+	"github.com/xanzy/go-gitlab"
+)
+
+type fakeCommentClient struct {
+	testBase
+}
+
+func (f fakeCommentClient) CreateMergeRequestDiscussion(pid interface{}, mergeRequest int, opt *gitlab.CreateMergeRequestDiscussionOptions, options ...gitlab.RequestOptionFunc) (*gitlab.Discussion, *gitlab.Response, error) {
+	resp, err := f.handleGitlabError()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return &gitlab.Discussion{Notes: []*gitlab.Note{{}}}, resp, err
+}
+func (f fakeCommentClient) UpdateMergeRequestDiscussionNote(pid interface{}, mergeRequest int, discussion string, note int, opt *gitlab.UpdateMergeRequestDiscussionNoteOptions, options ...gitlab.RequestOptionFunc) (*gitlab.Note, *gitlab.Response, error) {
+	resp, err := f.handleGitlabError()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return &gitlab.Note{}, resp, err
+}
+
+func (f fakeCommentClient) DeleteMergeRequestDiscussionNote(pid interface{}, mergeRequest int, discussion string, note int, options ...gitlab.RequestOptionFunc) (*gitlab.Response, error) {
+	resp, err := f.handleGitlabError()
+	if err != nil {
+		return nil, err
+	}
+	return resp, err
+}
+
+func TestPostComment(t *testing.T) {
+	var testCommentCreationData = PostCommentRequest{Comment: "Some comment"}
+	t.Run("Creates a new note (unlinked comment)", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPost, "/mr/comment", testCommentCreationData)
+		svc := commentService{testProjectData, fakeCommentClient{}}
+		data := getSuccessData(t, svc, request)
+		assert(t, data.Message, "Comment created successfully")
+		assert(t, data.Status, http.StatusOK)
+	})
+
+	t.Run("Creates a new comment", func(t *testing.T) {
+		testCommentCreationData := PostCommentRequest{ // Re-create comment creation data to avoid mutating this variable in other tests
+			Comment: "Some comment",
+			PositionData: PositionData{
+				FileName: "file.txt",
+			},
+		}
+		request := makeRequest(t, http.MethodPost, "/mr/comment", testCommentCreationData)
+		svc := commentService{testProjectData, fakeCommentClient{}}
+		data := getSuccessData(t, svc, request)
+		assert(t, data.Message, "Comment created successfully")
+		assert(t, data.Status, http.StatusOK)
+	})
+
+	t.Run("Handles errors from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPost, "/mr/comment", testCommentCreationData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{errFromGitlab: true}}}
+		data := getFailData(t, svc, request)
+		checkErrorFromGitlab(t, data, "Could not create discussion")
+	})
+
+	t.Run("Handles non-200s from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPost, "/mr/comment", testCommentCreationData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{status: http.StatusSeeOther}}}
+		data := getFailData(t, svc, request)
+		checkNon200(t, data, "Could not create discussion", "/mr/comment")
+	})
+}
+
+func TestDeleteComment(t *testing.T) {
+	var testCommentDeletionData = DeleteCommentRequest{NoteId: 3, DiscussionId: "abc123"}
+	t.Run("Deletes a comment", func(t *testing.T) {
+		request := makeRequest(t, http.MethodDelete, "/mr/comment", testCommentDeletionData)
+		svc := commentService{testProjectData, fakeCommentClient{}}
+		data := getSuccessData(t, svc, request)
+		assert(t, data.Message, "Comment deleted successfully")
+		assert(t, data.Status, http.StatusOK)
+	})
+	t.Run("Handles errors from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodDelete, "/mr/comment", testCommentDeletionData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{errFromGitlab: true}}}
+		data := getFailData(t, svc, request)
+		checkErrorFromGitlab(t, data, "Could not delete comment")
+	})
+
+	t.Run("Handles non-200s from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodDelete, "/mr/comment", testCommentDeletionData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{status: http.StatusSeeOther}}}
+		data := getFailData(t, svc, request)
+		checkNon200(t, data, "Could not delete comment", "/mr/comment")
+	})
+}
+
+func TestEditComment(t *testing.T) {
+	var testEditCommentData = EditCommentRequest{Comment: "Some comment", NoteId: 3, DiscussionId: "abc123"}
+	t.Run("Edits a comment", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPatch, "/mr/comment", testEditCommentData)
+		svc := commentService{testProjectData, fakeCommentClient{}}
+		data := getSuccessData(t, svc, request)
+		assert(t, data.Message, "Comment updated successfully")
+		assert(t, data.Status, http.StatusOK)
+	})
+	t.Run("Handles errors from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPatch, "/mr/comment", testEditCommentData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{errFromGitlab: true}}}
+		data := getFailData(t, svc, request)
+		checkErrorFromGitlab(t, data, "Could not update comment")
+	})
+
+	t.Run("Handles non-200s from Gitlab client", func(t *testing.T) {
+		request := makeRequest(t, http.MethodPatch, "/mr/comment", testEditCommentData)
+		svc := commentService{testProjectData, fakeCommentClient{testBase{status: http.StatusSeeOther}}}
+		data := getFailData(t, svc, request)
+		checkNon200(t, data, "Could not update comment", "/mr/comment")
+	})
+}