This question's explanation and your answers so far.
表計算ソフトを利用して, 次の 3 種類のワークシートを作成した。それぞれのワークシートをプログラムと考えるとき, これらのワークシートの動作を確認するテストのうち, 結合テストに相当するものはどれか。 (1) 4～9 月の各月の売上をすべて入力すると, その合計を計算するワークシート“上半期” (2) 10～3 月の各月の売上をすべて入力すると, その合計を計算するワークシート“下半期” (3) ワークシート“上半期”の売上合計とワークシート“下半期”の売上合計を加えて年間の売上合計を自動計算し, 月別のグラフを表示するワークシート“年間”
This test looks at whether the sales total on each worksheet becomes an error when one month of sales is not entered, and what it verifies is the input-check processing inside “First Half” and “Second Half” separately. Because it does not go through the handover between worksheets at all, it is unit testing (a test of an abnormal case).
This enters the sales of the months each worksheet is in charge of and checks that the half-year sales total is calculated correctly within that worksheet. It verifies the function of a single module on its own, that is, unit testing. It does not verify the handover of data to “Annual”.
正解 Integration testing (also called combined testing) is the stage that combines several modules which have already finished unit testing and checks whether the handover of data between the modules (the interface) works correctly. This question regards each worksheet as one program, so “First Half” and “Second Half” are modules that each produce a half-year total on their own, while “Annual” corresponds to the module that receives the outputs of those two, automatically calculates the annual sales total, and displays a graph by month. Choice ウ checks whether the sales totals calculated in “First Half” and “Second Half” are correctly reflected in “Annual” — that is, it checks the very part where data is linked across worksheets, which is exactly integration testing.
Both the summing of the half-year totals and the annual sales total are worked out by hand, and the two results are merely checked against each other; the automatic calculation of worksheet “Annual” and the handover of data between worksheets are never actually run and confirmed. Since the program interface is not verified, this is not integration testing but merely a manual recalculation that checks by hand whether the result is correct.