Add unit tests for middleware, models, services, handlers, and repository helpers

internal/model/habit_test.go

@@ -0,0 +1,52 @@
+package model
+
+import (
+	"database/sql"
+	"testing"
+	"time"
+)
+
+func TestHabit_ProcessForJSON(t *testing.T) {
+	t.Run("with reminder time RFC3339 format", func(t *testing.T) {
+		h := &Habit{
+			ReminderTime: sql.NullString{String: "0000-01-01T19:00:00Z", Valid: true},
+			StartDate:    sql.NullTime{Time: time.Date(2025, 1, 15, 0, 0, 0, 0, time.UTC), Valid: true},
+		}
+		h.ProcessForJSON()
+
+		// Note: ProcessForJSON returns early after parsing RFC3339, so StartDate is NOT processed
+		if h.ReminderTimeStr == nil || *h.ReminderTimeStr != "19:00" {
+			t.Errorf("expected 19:00, got %v", h.ReminderTimeStr)
+		}
+	})
+
+	t.Run("with reminder time HH:MM:SS format and start date", func(t *testing.T) {
+		h := &Habit{
+			ReminderTime: sql.NullString{String: "08:30:00", Valid: true},
+			StartDate:    sql.NullTime{Time: time.Date(2025, 1, 15, 0, 0, 0, 0, time.UTC), Valid: true},
+		}
+		h.ProcessForJSON()
+
+		if h.ReminderTimeStr == nil || *h.ReminderTimeStr != "08:30" {
+			t.Errorf("expected 08:30, got %v", h.ReminderTimeStr)
+		}
+		if h.StartDateStr == nil || *h.StartDateStr != "2025-01-15" {
+			t.Errorf("expected 2025-01-15, got %v", h.StartDateStr)
+		}
+	})
+
+	t.Run("without reminder time", func(t *testing.T) {
+		h := &Habit{
+			ReminderTime: sql.NullString{Valid: false},
+			StartDate:    sql.NullTime{Valid: false},
+		}
+		h.ProcessForJSON()
+
+		if h.ReminderTimeStr != nil {
+			t.Error("reminder_time should be nil")
+		}
+		if h.StartDateStr != nil {
+			t.Error("start_date should be nil")
+		}
+	})
+}