Support requesting copilot as a reviewer

Author: williammartin

e2e/e2e_test.go

@@ -369,3 +369,148 @@ func TestTags(t *testing.T) {
 	require.Equal(t, "v0.0.1", trimmedTag[0].Name, "expected tag name to match")
 	require.Equal(t, *ref.Object.SHA, trimmedTag[0].Commit.SHA, "expected tag SHA to match")
 }
+
+func TestRequestCopilotReview(t *testing.T) {
+	t.Parallel()
+
+	mcpClient := setupMCPClient(t)
+
+	ctx := context.Background()
+
+	// First, who am I
+	getMeRequest := mcp.CallToolRequest{}
+	getMeRequest.Params.Name = "get_me"
+
+	t.Log("Getting current user...")
+	resp, err := mcpClient.CallTool(ctx, getMeRequest)
+	require.NoError(t, err, "expected to call 'get_me' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	require.False(t, resp.IsError, "expected result not to be an error")
+	require.Len(t, resp.Content, 1, "expected content to have one item")
+
+	textContent, ok := resp.Content[0].(mcp.TextContent)
+	require.True(t, ok, "expected content to be of type TextContent")
+
+	var trimmedGetMeText struct {
+		Login string `json:"login"`
+	}
+	err = json.Unmarshal([]byte(textContent.Text), &trimmedGetMeText)
+	require.NoError(t, err, "expected to unmarshal text content successfully")
+
+	currentOwner := trimmedGetMeText.Login
+
+	// Then create a repository with a README (via autoInit)
+	repoName := fmt.Sprintf("github-mcp-server-e2e-%s-%d", t.Name(), time.Now().UnixMilli())
+	createRepoRequest := mcp.CallToolRequest{}
+	createRepoRequest.Params.Name = "create_repository"
+	createRepoRequest.Params.Arguments = map[string]any{
+		"name":     repoName,
+		"private":  true,
+		"autoInit": true,
+	}
+
+	t.Logf("Creating repository %s/%s...", currentOwner, repoName)
+	_, err = mcpClient.CallTool(ctx, createRepoRequest)
+	require.NoError(t, err, "expected to call 'get_me' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	// Cleanup the repository after the test
+	t.Cleanup(func() {
+		// MCP Server doesn't support deletions, but we can use the GitHub Client
+		ghClient := gogithub.NewClient(nil).WithAuthToken(getE2EToken(t))
+		t.Logf("Deleting repository %s/%s...", currentOwner, repoName)
+		_, err := ghClient.Repositories.Delete(context.Background(), currentOwner, repoName)
+		require.NoError(t, err, "expected to delete repository successfully")
+	})
+
+	// Create a branch on which to create a new commit
+	createBranchRequest := mcp.CallToolRequest{}
+	createBranchRequest.Params.Name = "create_branch"
+	createBranchRequest.Params.Arguments = map[string]any{
+		"owner":       currentOwner,
+		"repo":        repoName,
+		"branch":      "test-branch",
+		"from_branch": "main",
+	}
+
+	t.Logf("Creating branch in %s/%s...", currentOwner, repoName)
+	resp, err = mcpClient.CallTool(ctx, createBranchRequest)
+	require.NoError(t, err, "expected to call 'create_branch' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	// Create a commit with a new file
+	commitRequest := mcp.CallToolRequest{}
+	commitRequest.Params.Name = "create_or_update_file"
+	commitRequest.Params.Arguments = map[string]any{
+		"owner":   currentOwner,
+		"repo":    repoName,
+		"path":    "test-file.txt",
+		"content": fmt.Sprintf("Created by e2e test %s", t.Name()),
+		"message": "Add test file",
+		"branch":  "test-branch",
+	}
+
+	t.Logf("Creating commit with new file in %s/%s...", currentOwner, repoName)
+	resp, err = mcpClient.CallTool(ctx, commitRequest)
+	require.NoError(t, err, "expected to call 'create_or_update_file' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	textContent, ok = resp.Content[0].(mcp.TextContent)
+	require.True(t, ok, "expected content to be of type TextContent")
+
+	var trimmedCommitText struct {
+		SHA string `json:"sha"`
+	}
+	err = json.Unmarshal([]byte(textContent.Text), &trimmedCommitText)
+	require.NoError(t, err, "expected to unmarshal text content successfully")
+	commitId := trimmedCommitText.SHA
+
+	// Create a pull request
+	prRequest := mcp.CallToolRequest{}
+	prRequest.Params.Name = "create_pull_request"
+	prRequest.Params.Arguments = map[string]any{
+		"owner":    currentOwner,
+		"repo":     repoName,
+		"title":    "Test PR",
+		"body":     "This is a test PR",
+		"head":     "test-branch",
+		"base":     "main",
+		"commitId": commitId,
+	}
+
+	t.Logf("Creating pull request in %s/%s...", currentOwner, repoName)
+	resp, err = mcpClient.CallTool(ctx, prRequest)
+	require.NoError(t, err, "expected to call 'create_pull_request' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	// Request a copilot review
+	requestCopilotReviewRequest := mcp.CallToolRequest{}
+	requestCopilotReviewRequest.Params.Name = "request_copilot_review"
+	requestCopilotReviewRequest.Params.Arguments = map[string]any{
+		"owner":      currentOwner,
+		"repo":       repoName,
+		"pullNumber": 1,
+	}
+
+	t.Logf("Requesting Copilot review for pull request in %s/%s...", currentOwner, repoName)
+	resp, err = mcpClient.CallTool(ctx, requestCopilotReviewRequest)
+	require.NoError(t, err, "expected to call 'request_copilot_review' tool successfully")
+	require.False(t, resp.IsError, fmt.Sprintf("expected result not to be an error: %+v", resp))
+
+	textContent, ok = resp.Content[0].(mcp.TextContent)
+	require.True(t, ok, "expected content to be of type TextContent")
+	require.Equal(t, "", textContent.Text, "expected content to be empty")
+
+	// Finally, get requested reviews and see copilot is in there
+	// MCP Server doesn't support requesting reviews yet, but we can use the GitHub Client
+	ghClient := gogithub.NewClient(nil).WithAuthToken(getE2EToken(t))
+	t.Logf("Getting reviews for pull request in %s/%s...", currentOwner, repoName)
+	reviewRequests, _, err := ghClient.PullRequests.ListReviewers(context.Background(), currentOwner, repoName, 1, nil)
+	require.NoError(t, err, "expected to get review requests successfully")
+
+	// Check that there is one review request from copilot
+	require.Len(t, reviewRequests.Users, 1, "expected to find one review request")
+	require.Equal(t, "Copilot", *reviewRequests.Users[0].Login, "expected review request to be for Copilot")
+	require.Equal(t, "Bot", *reviewRequests.Users[0].Type, "expected review request to be for Bot")
+}

pkg/github/helper_test.go

@@ -10,6 +10,23 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+type expectations struct {
+	path        string
+	queryParams map[string]string
+	requestBody any
+}
+
+// expect is a helper function to create a partial mock that expects various
+// request behaviors, such as path, query parameters, and request body.
+func expect(t *testing.T, e expectations) *partialMock {
+	return &partialMock{
+		t:                   t,
+		expectedPath:        e.path,
+		expectedQueryParams: e.queryParams,
+		expectedRequestBody: e.requestBody,
+	}
+}
+
 // expectPath is a helper function to create a partial mock that expects a
 // request with the given path, with the ability to chain a response handler.
 func expectPath(t *testing.T, expectedPath string) *partialMock {

pkg/github/pullrequests.go

@@ -1248,9 +1248,15 @@ func CreatePullRequest(getClient GetClientFn, t translations.TranslationHelperFu
 }
 
 // RequestCopilotReview creates a tool to request a Copilot review for a pull request.
-func RequestCopilotReview(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
+// Note that this tool will not work on GHES where this feature is unsupported. In future, we should not expose this
+// tool if the configured host does not support it.
+func RequestCopilotReview(getClient GetClientFn, t translations.TranslationHelperFunc) (mcp.Tool, server.ToolHandlerFunc) {
 	return mcp.NewTool("request_copilot_review",
 			mcp.WithDescription(t("TOOL_REQUEST_COPILOT_REVIEW_DESCRIPTION", "Request a GitHub Copilot review for a pull request. Note: This feature depends on GitHub API support and may not be available for all users.")),
+			mcp.WithToolAnnotation(mcp.ToolAnnotation{
+				Title:        t("TOOL_REQUEST_COPILOT_REVIEW_USER_TITLE", "Request Copilot review"),
+				ReadOnlyHint: toBoolPtr(false),
+			}),
 			mcp.WithString("owner",
 				mcp.Required(),
 				mcp.Description("Repository owner"),
@@ -1259,7 +1265,7 @@ func RequestCopilotReview(getClient GetClientFn, t translations.TranslationHelpe
 				mcp.Required(),
 				mcp.Description("Repository name"),
 			),
-			mcp.WithNumber("pull_number",
+			mcp.WithNumber("pullNumber",
 				mcp.Required(),
 				mcp.Description("Pull request number"),
 			),
@@ -1269,17 +1275,46 @@ func RequestCopilotReview(getClient GetClientFn, t translations.TranslationHelpe
 			if err != nil {
 				return mcp.NewToolResultError(err.Error()), nil
 			}
+
 			repo, err := requiredParam[string](request, "repo")
 			if err != nil {
 				return mcp.NewToolResultError(err.Error()), nil
 			}
-			pullNumber, err := RequiredInt(request, "pull_number")
+
+			pullNumber, err := RequiredInt(request, "pullNumber")
+			if err != nil {
+				return mcp.NewToolResultError(err.Error()), nil
+			}
+
+			client, err := getClient(ctx)
 			if err != nil {
 				return mcp.NewToolResultError(err.Error()), nil
 			}
 
-			// As of now, GitHub API does not support Copilot as a reviewer programmatically.
-			// This is a placeholder for future support.
-			return mcp.NewToolResultError(fmt.Sprintf("Requesting a Copilot review for PR #%d in %s/%s is not currently supported by the GitHub API. Please request a Copilot review via the GitHub UI.", pullNumber, owner, repo)), nil
+			_, resp, err := client.PullRequests.RequestReviewers(
+				ctx,
+				owner,
+				repo,
+				pullNumber,
+				github.ReviewersRequest{
+					// The login name of the copilot reviewer bot
+					Reviewers: []string{"copilot-pull-request-reviewer[bot]"},
+				},
+			)
+			if err != nil {
+				return nil, fmt.Errorf("failed to request copilot review: %w", err)
+			}
+			defer func() { _ = resp.Body.Close() }()
+
+			if resp.StatusCode != http.StatusCreated {
+				body, err := io.ReadAll(resp.Body)
+				if err != nil {
+					return nil, fmt.Errorf("failed to read response body: %w", err)
+				}
+				return mcp.NewToolResultError(fmt.Sprintf("failed to request copilot review: %s", string(body))), nil
+			}
+
+			// Return nothing on success, as there's not much value in returning the Pull Request itself
+			return mcp.NewToolResultText(""), nil
 		}
 }

pkg/github/pullrequests_test.go

@@ -1918,25 +1918,110 @@ func Test_AddPullRequestReviewComment(t *testing.T) {
 }
 
 func Test_RequestCopilotReview(t *testing.T) {
+	t.Parallel()
+
 	mockClient := github.NewClient(nil)
-	tool, handler := RequestCopilotReview(stubGetClientFn(mockClient), translations.NullTranslationHelper)
+	tool, _ := RequestCopilotReview(stubGetClientFn(mockClient), translations.NullTranslationHelper)
 
 	assert.Equal(t, "request_copilot_review", tool.Name)
 	assert.NotEmpty(t, tool.Description)
 	assert.Contains(t, tool.InputSchema.Properties, "owner")
 	assert.Contains(t, tool.InputSchema.Properties, "repo")
-	assert.Contains(t, tool.InputSchema.Properties, "pull_number")
-	assert.ElementsMatch(t, tool.InputSchema.Required, []string{"owner", "repo", "pull_number"})
-
-	request := createMCPRequest(map[string]interface{}{
-		"owner":       "owner",
-		"repo":        "repo",
-		"pull_number": float64(42),
-	})
-
-	result, err := handler(context.Background(), request)
-	assert.NoError(t, err)
-	assert.NotNil(t, result)
-	textContent := getTextResult(t, result)
-	assert.Contains(t, textContent.Text, "not currently supported by the GitHub API")
+	assert.Contains(t, tool.InputSchema.Properties, "pullNumber")
+	assert.ElementsMatch(t, tool.InputSchema.Required, []string{"owner", "repo", "pullNumber"})
+
+	// Setup mock PR for success case
+	mockPR := &github.PullRequest{
+		Number:  github.Ptr(42),
+		Title:   github.Ptr("Test PR"),
+		State:   github.Ptr("open"),
+		HTMLURL: github.Ptr("https://github.com/owner/repo/pull/42"),
+		Head: &github.PullRequestBranch{
+			SHA: github.Ptr("abcd1234"),
+			Ref: github.Ptr("feature-branch"),
+		},
+		Base: &github.PullRequestBranch{
+			Ref: github.Ptr("main"),
+		},
+		Body: github.Ptr("This is a test PR"),
+		User: &github.User{
+			Login: github.Ptr("testuser"),
+		},
+	}
+
+	tests := []struct {
+		name           string
+		mockedClient   *http.Client
+		requestArgs    map[string]any
+		expectError    bool
+		expectedErrMsg string
+	}{
+		{
+			name: "successful request",
+			mockedClient: mock.NewMockedHTTPClient(
+				mock.WithRequestMatchHandler(
+					mock.PostReposPullsRequestedReviewersByOwnerByRepoByPullNumber,
+					expect(t, expectations{
+						path: "/repos/owner/repo/pulls/1/requested_reviewers",
+						requestBody: map[string]any{
+							"reviewers": []any{"copilot-pull-request-reviewer[bot]"},
+						},
+					}).andThen(
+						mockResponse(t, http.StatusCreated, mockPR),
+					),
+				),
+			),
+			requestArgs: map[string]any{
+				"owner":      "owner",
+				"repo":       "repo",
+				"pullNumber": float64(1),
+			},
+			expectError: false,
+		},
+		{
+			name: "request fails",
+			mockedClient: mock.NewMockedHTTPClient(
+				mock.WithRequestMatchHandler(
+					mock.PostReposPullsRequestedReviewersByOwnerByRepoByPullNumber,
+					http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+						w.WriteHeader(http.StatusNotFound)
+						_, _ = w.Write([]byte(`{"message": "Not Found"}`))
+					}),
+				),
+			),
+			requestArgs: map[string]any{
+				"owner":      "owner",
+				"repo":       "repo",
+				"pullNumber": float64(999),
+			},
+			expectError:    true,
+			expectedErrMsg: "failed to request copilot review",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			client := github.NewClient(tc.mockedClient)
+			_, handler := RequestCopilotReview(stubGetClientFn(client), translations.NullTranslationHelper)
+
+			request := createMCPRequest(tc.requestArgs)
+
+			result, err := handler(context.Background(), request)
+
+			if tc.expectError {
+				require.Error(t, err)
+				assert.Contains(t, err.Error(), tc.expectedErrMsg)
+				return
+			}
+
+			require.NoError(t, err)
+			assert.NotNil(t, result)
+			assert.Len(t, result.Content, 1)
+
+			textContent := getTextResult(t, result)
+			require.Equal(t, "", textContent.Text)
+		})
+	}
 }

pkg/github/tools.go

@@ -69,6 +69,8 @@ func InitToolsets(passedToolsets []string, readOnly bool, getClient GetClientFn,
 			toolsets.NewServerTool(CreatePullRequest(getClient, t)),
 			toolsets.NewServerTool(UpdatePullRequest(getClient, t)),
 			toolsets.NewServerTool(AddPullRequestReviewComment(getClient, t)),
+
+			toolsets.NewServerTool(RequestCopilotReview(getClient, t)),
 		)
 	codeSecurity := toolsets.NewToolset("code_security", "Code security related tools, such as GitHub Code Scanning").
 		AddReadTools(