Writing MSTest Tests Help users write effective, modern unit tests with MSTest 3.x/4.x using current APIs and best practices. When to Use - User wants to write new MSTest unit tests - User wants to improve or modernize existing MSTest tests by implementing concrete fixes - User asks about MSTest assertion APIs, data-driven patterns, or test lifecycle - User asks to replace with more specific assertions (collections, nulls, types, comparisons) - User asks to replace hard casts with type-checking assertions in tests - User needs help fixing a specific MSTest test bug or failing assertion - User…