I otherwise get:
Expected stderr to match:
expect-err> CMake Error at AppendNotOutput.cmake:1 \(add_custom_command\):
expect-err> add_custom_command given APPEND option with output.*
expect-err> which is not already a custom command output.
expect-err> Call Stack \(most recent call first\):
expect-err> CMakeLists.txt:3 \(include\)
Actual stderr:
actual-err> CMake Error at AppendNotOutput.cmake:1 (add_custom_command):
actual-err> add_custom_command given APPEND option with output
actual-err> "/home/stephen/dev/src/cmake/with
actual-err> space/Tests/RunCMake/add_custom_command/AppendNotOutput-build/out" which is
actual-err> not already a custom command output.
actual-err> Call Stack (most recent call first):
actual-err> CMakeLists.txt:3 (include)
Using a specific line for paths is a style already used elsewhere for
the same reason, such as CMP0041 output.
92d76b50aa