Merge branch 'improve-file-download'

Conflicts:
	Modules/ExternalProject.cmake

3 files changed, 46 insertions, 0 deletions

diff --git a/Tests/CMakeTests/CMakeLists.txt b/Tests/CMakeTests/CMakeLists.txt
index 7a176e9..3e5f08c 100644
--- a/Tests/CMakeTests/CMakeLists.txt
+++ b/Tests/CMakeTests/CMakeLists.txt
@@ -28,6 +28,11 @@ AddCMakeTest(Math "")
 AddCMakeTest(CMakeMinimumRequired "")
 AddCMakeTest(CompilerIdVendor "")
 
+AddCMakeTest(FileDownload "")
+set_property(TEST CMake.FileDownload PROPERTY
+  PASS_REGULAR_EXPRESSION "file already exists with expected MD5 sum"
+  )
+
 if(HAVE_ELF_H)
   AddCMakeTest(ELF "")
 endif()
diff --git a/Tests/CMakeTests/FileDownloadInput.png b/Tests/CMakeTests/FileDownloadInput.png
new file mode 100644
index 0000000..7bbcee4
--- /dev/null
+++ b/Tests/CMakeTests/FileDownloadInput.png
diff --git a/Tests/CMakeTests/FileDownloadTest.cmake.in b/Tests/CMakeTests/FileDownloadTest.cmake.in
new file mode 100644
index 0000000..578f510
--- /dev/null
+++ b/Tests/CMakeTests/FileDownloadTest.cmake.in
@@ -0,0 +1,41 @@
+set(url "file://@CMAKE_CURRENT_SOURCE_DIR@/FileDownloadInput.png")
+set(dir "@CMAKE_CURRENT_BINARY_DIR@/downloads")
+
+message(STATUS "FileDownload:1")
+file(DOWNLOAD
+  ${url}
+  ${dir}/file1.png
+  TIMEOUT 2
+  )
+
+message(STATUS "FileDownload:2")
+file(DOWNLOAD
+  ${url}
+  ${dir}/file2.png
+  TIMEOUT 2
+  SHOW_PROGRESS
+  )
+
+# Two calls in a row, exactly the same arguments.
+# Since downloaded file should exist already for 2nd call,
+# the 2nd call will short-circuit and return early...
+#
+if(EXISTS ${dir}/file3.png)
+  file(REMOVE ${dir}/file3.png)
+endif()
+
+message(STATUS "FileDownload:3")
+file(DOWNLOAD
+  ${url}
+  ${dir}/file3.png
+  TIMEOUT 2
+  EXPECTED_MD5 d16778650db435bda3a8c3435c3ff5d1
+  )
+
+message(STATUS "FileDownload:4")
+file(DOWNLOAD
+  ${url}
+  ${dir}/file3.png
+  TIMEOUT 2
+  EXPECTED_MD5 d16778650db435bda3a8c3435c3ff5d1
+  )