Moving to scaleset client for the controller (#4390)

controllers/actions.github.com/multiclient/fake/multi_client.go

@@ -0,0 +1,53 @@
+package fake
+
+import (
+	"context"
+
+	"github.com/actions/actions-runner-controller/controllers/actions.github.com/multiclient"
+)
+
+// MultiClientOption is a functional option for configuring a fake MultiClient
+type MultiClientOption func(*MultiClient)
+
+// WithClient configures the client that GetClientFor will return
+func WithClient(c multiclient.Client) MultiClientOption {
+	return func(mc *MultiClient) {
+		mc.client = c
+	}
+}
+
+// WithGetClientForError configures an error that GetClientFor will return
+func WithGetClientForError(err error) MultiClientOption {
+	return func(mc *MultiClient) {
+		mc.getClientForErr = err
+	}
+}
+
+// MultiClient implements multiclient.MultiClient interface for testing
+type MultiClient struct {
+	client          multiclient.Client
+	getClientForErr error
+}
+
+// Compile-time interface check
+var _ multiclient.MultiClient = (*MultiClient)(nil)
+
+// NewMultiClient creates a new fake MultiClient with the given options
+func NewMultiClient(opts ...MultiClientOption) *MultiClient {
+	mc := &MultiClient{}
+	for _, opt := range opts {
+		opt(mc)
+	}
+	// Default behavior: if no client configured, return a default NewClient()
+	if mc.client == nil {
+		mc.client = NewClient()
+	}
+	return mc
+}
+
+func (mc *MultiClient) GetClientFor(ctx context.Context, opts *multiclient.ClientForOptions) (multiclient.Client, error) {
+	if mc.getClientForErr != nil {
+		return nil, mc.getClientForErr
+	}
+	return mc.client, nil
+}