From 99d6de6c1a5871ba03fa008c984cd5408940c3cd Mon Sep 17 00:00:00 2001
From: Ben Boeckel <ben.boeckel@kitware.com>
Date: Mon, 27 Feb 2017 11:30:13 -0500
Subject: ExternalProject: only append `COMMAND` if actually adding a command

Fixes #16544.
---
 Modules/ExternalProject.cmake        |  5 ++---
 Tests/ExternalProject/CMakeLists.txt | 10 ++++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Modules/ExternalProject.cmake b/Modules/ExternalProject.cmake
index 00781d6..97438e6 100644
--- a/Modules/ExternalProject.cmake
+++ b/Modules/ExternalProject.cmake
@@ -1987,11 +1987,10 @@ function(_ep_add_download_command name)
         set(comment "Performing download step (${steps}) for '${name}'")
         _ep_write_verifyfile_script("${stamp_dir}/verify-${name}.cmake" "${file}" "${hash}")
       endif()
-      list(APPEND cmd ${CMAKE_COMMAND} -P ${stamp_dir}/verify-${name}.cmake
-        COMMAND)
+      list(APPEND cmd ${CMAKE_COMMAND} -P ${stamp_dir}/verify-${name}.cmake)
       if (NOT no_extract)
         _ep_write_extractfile_script("${stamp_dir}/extract-${name}.cmake" "${name}" "${file}" "${source_dir}")
-        list(APPEND cmd ${CMAKE_COMMAND} -P ${stamp_dir}/extract-${name}.cmake)
+        list(APPEND cmd COMMAND ${CMAKE_COMMAND} -P ${stamp_dir}/extract-${name}.cmake)
       else ()
         set_property(TARGET ${name} PROPERTY _EP_DOWNLOADED_FILE ${file})
       endif ()
diff --git a/Tests/ExternalProject/CMakeLists.txt b/Tests/ExternalProject/CMakeLists.txt
index 72c20eb..6b73563 100644
--- a/Tests/ExternalProject/CMakeLists.txt
+++ b/Tests/ExternalProject/CMakeLists.txt
@@ -90,6 +90,16 @@ ExternalProject_Add(${proj}
 )
 set_property(TARGET ${proj} PROPERTY FOLDER "")
 
+set(proj NoExtractLogDownload)
+ExternalProject_Add(${proj}
+  URL ${CMAKE_CURRENT_SOURCE_DIR}/gitrepo.tgz
+  DOWNLOAD_NO_EXTRACT 1
+  LOG_DOWNLOAD 1
+  BUILD_COMMAND ""
+  CONFIGURE_COMMAND ""
+  INSTALL_COMMAND ""
+)
+
 
 # CVS-based tests:
 #
-- 
cgit v0.12