From c0da651c09e11f9868529b7f8c4dc8f97c4546c8 Mon Sep 17 00:00:00 2001
From: Johnny Jazeix <jazeix@gmail.com>
Date: Mon, 23 Dec 2019 10:35:41 +0100
Subject: file(DOWNLOAD): Don't fail if given just a filename to write to

Fixes: #17969
---
 Source/cmFileCommand.cxx                   |  3 ++-
 Tests/CMakeTests/FileDownloadTest.cmake.in | 18 ++++++++++++++++++
 Tests/CMakeTests/FileTestScript.cmake      |  2 +-
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index 1fdfa87..d1775a7 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -1707,7 +1707,8 @@ bool HandleDownloadCommand(std::vector<std::string> const& args,
   // as we receive downloaded bits from curl...
   //
   std::string dir = cmSystemTools::GetFilenamePath(file);
-  if (!cmSystemTools::FileExists(dir) && !cmSystemTools::MakeDirectory(dir)) {
+  if (!dir.empty() && !cmSystemTools::FileExists(dir) &&
+      !cmSystemTools::MakeDirectory(dir)) {
     std::string errstring = "DOWNLOAD error: cannot create directory '" + dir +
       "' - Specify file by full path name and verify that you "
       "have directory creation and file write privileges.";
diff --git a/Tests/CMakeTests/FileDownloadTest.cmake.in b/Tests/CMakeTests/FileDownloadTest.cmake.in
index 6c1ee75..5bd3803 100644
--- a/Tests/CMakeTests/FileDownloadTest.cmake.in
+++ b/Tests/CMakeTests/FileDownloadTest.cmake.in
@@ -145,3 +145,21 @@ file(DOWNLOAD
   )
 message(STATUS "${status}")
 __reportIfWrongStatus("${status}" 6) # 6 corresponds to an unresolvable host name
+
+message(STATUS "FileDownload:12")
+set(absFile "@CMAKE_CURRENT_BINARY_DIR@/file12.png")
+if(EXISTS "${absFile}")
+  file(RENAME ${absFile} "${absFile}_beingRemoved")
+  file(REMOVE "${absFile}_beingRemoved")
+endif()
+file(DOWNLOAD
+  ${url}
+  file12.png
+  TIMEOUT ${timeout}
+  EXPECTED_MD5 dbd330d52f4dbd60115d4191904ded92
+  STATUS status
+  )
+__reportIfWrongStatus("${status}" 0)
+if(NOT EXISTS file12.png)
+  message(SEND_ERROR "file12.png not downloaded: ${status}")
+endif()
diff --git a/Tests/CMakeTests/FileTestScript.cmake b/Tests/CMakeTests/FileTestScript.cmake
index 9a43569..145f28a 100644
--- a/Tests/CMakeTests/FileTestScript.cmake
+++ b/Tests/CMakeTests/FileTestScript.cmake
@@ -183,7 +183,7 @@ elseif(testname STREQUAL to_native_path) # pass
 elseif(testname STREQUAL download_wrong_number_of_args) # fail
   file(DOWNLOAD zzzz://bogus/ffff)
 
-elseif(testname STREQUAL download_file_with_no_path) # fail
+elseif(testname STREQUAL download_file_with_no_path) # pass
   file(DOWNLOAD zzzz://bogus/ffff ffff)
 
 elseif(testname STREQUAL download_missing_time) # fail
-- 
cgit v0.12