Reject typed nil Taskwarrior injection for vq0

2 files changed, 34 insertions, 7 deletions

diff --git a/internal/ui/table.go b/internal/ui/table.go
index 774954c..d4c9d46 100644
--- a/internal/ui/table.go
+++ b/internal/ui/table.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"reflect"
 	"regexp"
 	"strconv"
 	"strings"
@@ -363,12 +364,26 @@ func blinkCmd() tea.Cmd {
 }
 
 func (m *Model) taskwarriorClient() task.Taskwarrior {
-	if m.taskwarrior == nil {
+	if isNilTaskwarrior(m.taskwarrior) {
 		panic("ui.Model Taskwarrior client is nil; use ui.New or ui.NewWithTaskwarrior")
 	}
 	return m.taskwarrior
 }
 
+func isNilTaskwarrior(tw task.Taskwarrior) bool {
+	if tw == nil {
+		return true
+	}
+
+	value := reflect.ValueOf(tw)
+	switch value.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Pointer, reflect.Slice:
+		return value.IsNil()
+	default:
+		return false
+	}
+}
+
 // clearEditingModes ensures only one editing mode is active at a time
 func (m *Model) clearEditingModes() {
 	m.annotating = false
@@ -453,7 +468,7 @@ func New(filters []string, browserCmd string) (Model, error) {
 
 // NewWithTaskwarrior creates a UI model using the provided Taskwarrior client.
 func NewWithTaskwarrior(filters []string, browserCmd string, tw task.Taskwarrior) (Model, error) {
-	if tw == nil {
+	if isNilTaskwarrior(tw) {
 		return Model{}, errors.New("taskwarrior client is nil")
 	}
 	m := Model{filters: filters, browserCmd: browserCmd, agentFilterHotkey: "3", taskwarrior: tw, blinkState: blinkState{blinkEnabled: true}}
diff --git a/internal/ui/table_test.go b/internal/ui/table_test.go
index a9348ba..14e78ca 100644
--- a/internal/ui/table_test.go
+++ b/internal/ui/table_test.go
@@ -188,12 +188,24 @@ func TestNewWithTaskwarriorUsesFakeForAddTask(t *testing.T) {
 }
 
 func TestNewWithTaskwarriorRejectsNilClient(t *testing.T) {
-	_, err := NewWithTaskwarrior(nil, "firefox", nil)
-	if err == nil {
-		t.Fatalf("NewWithTaskwarrior with nil client succeeded")
+	tests := []struct {
+		name string
+		tw   task.Taskwarrior
+	}{
+		{name: "plain nil", tw: nil},
+		{name: "typed nil", tw: (*fakeTaskwarrior)(nil)},
 	}
-	if got, want := err.Error(), "taskwarrior client is nil"; got != want {
-		t.Fatalf("NewWithTaskwarrior error = %q, want %q", got, want)
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			_, err := NewWithTaskwarrior(nil, "firefox", tc.tw)
+			if err == nil {
+				t.Fatalf("NewWithTaskwarrior with nil client succeeded")
+			}
+			if got, want := err.Error(), "taskwarrior client is nil"; got != want {
+				t.Fatalf("NewWithTaskwarrior error = %q, want %q", got, want)
+			}
+		})
 	}
 }