ExternalProject: Add tests for UPDATE_COMMAND.

Tests are added for UPDATE_COMMAND to ensure it is working properly.  Testing
infrastructure is added along with tests for Git, but tests for other version
control systems could easily be added in the future.

1 files changed, 58 insertions, 0 deletions

diff --git a/Tests/ExternalProjectUpdate/ExternalProjectUpdateTest.cmake b/Tests/ExternalProjectUpdate/ExternalProjectUpdateTest.cmake
new file mode 100644
index 0000000..fed40ef
--- /dev/null
+++ b/Tests/ExternalProjectUpdate/ExternalProjectUpdateTest.cmake
@@ -0,0 +1,58 @@
+# Set the ExternalProject GIT_TAG to desired_tag, and make sure the
+# resulting checked out version is resulting_sha and a rebuild.
+# This check's the viability of the ExternalProject UPDATE_COMMAND.
+macro(check_a_tag desired_tag resulting_sha)
+  # Configure
+  execute_process(COMMAND ${CMAKE_COMMAND}
+    -G ${CMAKE_TEST_GENERATOR}
+    -DTEST_GIT_TAG:STRING=${desired_tag}
+    ${ExternalProjectUpdate_SOURCE_DIR}
+    WORKING_DIRECTORY ${ExternalProjectUpdate_BINARY_DIR}
+    RESULT_VARIABLE error_code
+    )
+  if(error_code)
+    message(FATAL_ERROR "Could not configure the project.")
+  endif()
+
+  # Build
+  execute_process(COMMAND ${CMAKE_COMMAND}
+    --build ${ExternalProjectUpdate_BINARY_DIR}
+    RESULT_VARIABLE error_code
+    )
+  if(error_code)
+    message(FATAL_ERROR "Could not build the project.")
+  endif()
+
+  # Check the resulting SHA
+  execute_process(COMMAND ${GIT_EXECUTABLE}
+    rev-list --max-count=1 HEAD
+    WORKING_DIRECTORY ${ExternalProjectUpdate_BINARY_DIR}/CMakeExternals/Source/TutorialStep1-GIT
+    RESULT_VARIABLE error_code
+    OUTPUT_VARIABLE tag_sha
+    )
+  if(error_code)
+    message(FATAL_ERROR "Could not check the sha.")
+  endif()
+
+  string(STRIP "${tag_sha}" tag_sha)
+  if(NOT (${tag_sha} STREQUAL ${resulting_sha}))
+    message(FATAL_ERROR "UPDATE_COMMAND produced
+  ${tag_sha}
+when
+  ${resulting_sha}
+was expected."
+    )
+  endif()
+endmacro()
+
+find_package(Git)
+if(GIT_EXECUTABLE)
+  check_a_tag(origin/master 5842b503ba4113976d9bb28d57b5aee1ad2736b7)
+  check_a_tag(tag1          d1970730310fe8bc07e73f15dc570071f9f9654a)
+  # With the Git UPDATE_COMMAND performance patch, this will not required a
+  # 'git fetch'
+  check_a_tag(tag1          d1970730310fe8bc07e73f15dc570071f9f9654a)
+  check_a_tag(tag2          5842b503ba4113976d9bb28d57b5aee1ad2736b7)
+  check_a_tag(d19707303     d1970730310fe8bc07e73f15dc570071f9f9654a)
+  check_a_tag(origin/master 5842b503ba4113976d9bb28d57b5aee1ad2736b7)
+endif()