Для меня тестдизайн это готовый комплекс сопроводительной документации для возможности проведения тестовых работ. И этот набор артефактов можно передать любому - даже не знакомому с проектом тестеру - и используя только данный набор артов - сотрудник может провести тестирование.
Ну, поскольку споры в стиле Нет-Да-Нет-Да в высшей мере контрпродуктивны, я аргументирую, пожалуй, цитатой из силлабуса ISTQB FL:
1.4.2 Test Activities and Tasks
A test process consists of the following main groups of activities: Test planning Test monitoring and control Test analysis Test design Test implementation Test execution Test completion
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Test design
During test design, the test conditions are elaborated into high-level test cases, sets of high-level test
cases, and other testware. So, test analysis answers the question “what to test?” while test design
answers the question “how to test?”
Test design includes the following major activities: Designing and prioritizing test cases and sets of test cases Identifying necessary test data to support test conditions and test cases Designing the test environment and identifying any required infrastructure and tools Capturing bi-directional traceability between the test basis, test conditions, and test cases (see
section 1.4.4)
The elaboration of test conditions into test cases and sets of test cases during test design often involves
using test techniques (see chapter 4).
As with test analysis, test design may also result in the identification of similar types of defects in the test
basis. Also, as with test analysis, the identification of defects during test design is an important potential
benefit.