package github
import (
"context"
"encoding/json"
"testing"
"github.com/github/github-mcp-server/pkg/translations"
"github.com/modelcontextprotocol/go-sdk/mcp"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"github.com/github/github-mcp-server/pkg/inventory"
"github.com/github/github-mcp-server/pkg/scopes"
"github.com/github/github-mcp-server/pkg/utils"
)
// RemoteMCPEnthusiasticGreeting is a dummy test feature flag .
const RemoteMCPEnthusiasticGreeting = "remote_mcp_enthusiastic_greeting"
// FeatureChecker is an interface for checking if a feature flag is enabled.
type FeatureChecker interface {
// IsFeatureEnabled checks if a feature flag is enabled.
IsFeatureEnabled(ctx context.Context, flagName string) bool
}
// HelloWorld returns a simple greeting tool that demonstrates feature flag conditional behavior.
// This tool is for testing and demonstration purposes only.
func HelloWorldTool(t translations.TranslationHelperFunc) inventory.ServerTool {
return NewTool(
ToolsetMetadataContext, // Use existing "context" toolset
mcp.Tool{
Name: "hello_world",
Description: t("TOOL_HELLO_WORLD_DESCRIPTION", "A simple greeting tool that demonstrates feature flag conditional behavior"),
Annotations: &mcp.ToolAnnotations{
Title: t("TOOL_HELLO_WORLD_TITLE", "Hello World"),
ReadOnlyHint: true,
},
},
[]scopes.Scope{},
func(ctx context.Context, deps ToolDependencies, _ *mcp.CallToolRequest, _ map[string]any) (*mcp.CallToolResult, any, error) {
// Check feature flag to determine greeting style
greeting := "Hello, world!"
if deps.IsFeatureEnabled(ctx, RemoteMCPEnthusiasticGreeting) {
greeting += " Welcome to the future of MCP! 🎉"
}
if deps.GetFlags(ctx).InsidersMode {
greeting += " Experimental features are enabled! 🚀"
}
// Build response
response := map[string]any{
"greeting": greeting,
}
jsonBytes, err := json.Marshal(response)
if err != nil {
return utils.NewToolResultError("failed to marshal response"), nil, nil
}
return utils.NewToolResultText(string(jsonBytes)), nil, nil
},
)
}
func TestHelloWorld_ConditionalBehavior_Featureflag(t *testing.T) {
t.Parallel()
tests := []struct {
name string
featureFlagEnabled bool
inputName string
expectedGreeting string
}{
{
name: "Feature flag disabled - default greeting",
featureFlagEnabled: false,
expectedGreeting: "Hello, world!",
},
{
name: "Feature flag enabled - enthusiastic greeting",
featureFlagEnabled: true,
expectedGreeting: "Hello, world! Welcome to the future of MCP! 🎉",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
// Create feature checker based on test case
checker := func(_ context.Context, flagName string) (bool, error) {
if flagName == RemoteMCPEnthusiasticGreeting {
return tt.featureFlagEnabled, nil
}
return false, nil
}
// Create deps with the checker
deps := NewBaseDeps(
nil, nil, nil, nil,
translations.NullTranslationHelper,
FeatureFlags{},
0,
checker,
)
// Get the tool and its handler
tool := HelloWorldTool(translations.NullTranslationHelper)
handler := tool.Handler(deps)
// Call the handler with deps in context
ctx := ContextWithDeps(context.Background(), deps)
result, err := handler(ctx, &mcp.CallToolRequest{
Params: &mcp.CallToolParamsRaw{
Arguments: json.RawMessage(`{}`),
},
})
require.NoError(t, err)
require.NotNil(t, result)
require.Len(t, result.Content, 1)
// Parse the response - should be TextContent
textContent, ok := result.Content[0].(*mcp.TextContent)
require.True(t, ok, "expected content to be TextContent")
var response map[string]any
err = json.Unmarshal([]byte(textContent.Text), &response)
require.NoError(t, err)
// Verify the greeting matches expected based on feature flag
assert.Equal(t, tt.expectedGreeting, response["greeting"])
})
}
}
func TestHelloWorld_ConditionalBehavior_Config(t *testing.T) {
t.Parallel()
tests := []struct {
name string
insidersMode bool
expectedGreeting string
}{
{
name: "Experimental disabled - default greeting",
insidersMode: false,
expectedGreeting: "Hello, world!",
},
{
name: "Experimental enabled - experimental greeting",
insidersMode: true,
expectedGreeting: "Hello, world! Experimental features are enabled! 🚀",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
// Create deps with the checker
deps := NewBaseDeps(
nil, nil, nil, nil,
translations.NullTranslationHelper,
FeatureFlags{InsidersMode: tt.insidersMode},
0,
nil,
)
// Get the tool and its handler
tool := HelloWorldTool(translations.NullTranslationHelper)
handler := tool.Handler(deps)
// Call the handler with deps in context
ctx := ContextWithDeps(context.Background(), deps)
result, err := handler(ctx, &mcp.CallToolRequest{
Params: &mcp.CallToolParamsRaw{
Arguments: json.RawMessage(`{}`),
},
})
require.NoError(t, err)
require.NotNil(t, result)
require.Len(t, result.Content, 1)
// Parse the response - should be TextContent
textContent, ok := result.Content[0].(*mcp.TextContent)
require.True(t, ok, "expected content to be TextContent")
var response map[string]any
err = json.Unmarshal([]byte(textContent.Text), &response)
require.NoError(t, err)
// Verify the greeting matches expected based on feature flag
assert.Equal(t, tt.expectedGreeting, response["greeting"])
})
}
}
