ExternalProject: Preserve empty string arguments

5 files changed, 46 insertions, 3 deletions

diff --git a/Tests/RunCMake/ExternalProject/NO_DEPENDS-stderr.txt b/Tests/RunCMake/ExternalProject/NO_DEPENDS-stderr.txt
index 4cb051d..928d88a 100644
--- a/Tests/RunCMake/ExternalProject/NO_DEPENDS-stderr.txt
+++ b/Tests/RunCMake/ExternalProject/NO_DEPENDS-stderr.txt
@@ -2,7 +2,7 @@ CMake Warning \(dev\) at .*/Modules/ExternalProject.cmake:[0-9]+. \(message\):
   Using NO_DEPENDS for "configure" step might break parallel builds
 Call Stack \(most recent call first\):
   .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_StepTargets\)
-  .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_Step\)
+  .*/Modules/ExternalProject.cmake:[0-9]+:EVAL:2 \(ExternalProject_Add_Step\)
   .*/Modules/ExternalProject.cmake:[0-9]+ \(_ep_add_configure_command\)
   NO_DEPENDS.cmake:[0-9]+ \(ExternalProject_Add\)
   CMakeLists.txt:[0-9]+ \(include\)
@@ -12,7 +12,7 @@ CMake Warning \(dev\) at .*/Modules/ExternalProject.cmake:[0-9]+. \(message\):
   Using NO_DEPENDS for "build" step might break parallel builds
 Call Stack \(most recent call first\):
   .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_StepTargets\)
-  .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_Step\)
+  .*/Modules/ExternalProject.cmake:[0-9]+:EVAL:2 \(ExternalProject_Add_Step\)
   .*/Modules/ExternalProject.cmake:[0-9]+ \(_ep_add_build_command\)
   NO_DEPENDS.cmake:[0-9]+ \(ExternalProject_Add\)
   CMakeLists.txt:[0-9]+ \(include\)
@@ -22,7 +22,7 @@ CMake Warning \(dev\) at .*/Modules/ExternalProject.cmake:[0-9]+. \(message\):
   Using NO_DEPENDS for "install" step might break parallel builds
 Call Stack \(most recent call first\):
   .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_StepTargets\)
-  .*/Modules/ExternalProject.cmake:[0-9]+ \(ExternalProject_Add_Step\)
+  .*/Modules/ExternalProject.cmake:[0-9]+:EVAL:2 \(ExternalProject_Add_Step\)
   .*/Modules/ExternalProject.cmake:[0-9]+ \(_ep_add_install_command\)
   NO_DEPENDS.cmake:[0-9]+ \(ExternalProject_Add\)
   CMakeLists.txt:[0-9]+ \(include\)
diff --git a/Tests/RunCMake/ExternalProject/PreserveEmptyArgs-build-stdout.txt b/Tests/RunCMake/ExternalProject/PreserveEmptyArgs-build-stdout.txt
new file mode 100644
index 0000000..0e21b8f
--- /dev/null
+++ b/Tests/RunCMake/ExternalProject/PreserveEmptyArgs-build-stdout.txt
@@ -0,0 +1,21 @@
+.*-- Number of arguments for download: 6
+.*-- download argument 4: ''
+.*-- download argument 5: 'after'
+.*-- Number of arguments for update: 6
+.*-- update argument 4: ''
+.*-- update argument 5: 'after'
+.*-- Number of arguments for patch: 6
+.*-- patch argument 4: ''
+.*-- patch argument 5: 'after'
+.*-- Number of arguments for configure: 6
+.*-- configure argument 4: ''
+.*-- configure argument 5: 'after'
+.*-- Number of arguments for build: 6
+.*-- build argument 4: ''
+.*-- build argument 5: 'after'
+.*-- Number of arguments for install: 6
+.*-- install argument 4: ''
+.*-- install argument 5: 'after'
+.*-- Number of arguments for test: 6
+.*-- test argument 4: ''
+.*-- test argument 5: 'after'
diff --git a/Tests/RunCMake/ExternalProject/PreserveEmptyArgs.cmake b/Tests/RunCMake/ExternalProject/PreserveEmptyArgs.cmake
new file mode 100644
index 0000000..ded1000
--- /dev/null
+++ b/Tests/RunCMake/ExternalProject/PreserveEmptyArgs.cmake
@@ -0,0 +1,13 @@
+include(ExternalProject)
+
+set(script "${CMAKE_CURRENT_LIST_DIR}/countArgs.cmake")
+ExternalProject_Add(
+  blankChecker
+  DOWNLOAD_COMMAND  ${CMAKE_COMMAND} -P "${script}" download  "" after
+  UPDATE_COMMAND    ${CMAKE_COMMAND} -P "${script}" update    "" after
+  PATCH_COMMAND     ${CMAKE_COMMAND} -P "${script}" patch     "" after
+  CONFIGURE_COMMAND ${CMAKE_COMMAND} -P "${script}" configure "" after
+  BUILD_COMMAND     ${CMAKE_COMMAND} -P "${script}" build     "" after
+  INSTALL_COMMAND   ${CMAKE_COMMAND} -P "${script}" install   "" after
+  TEST_COMMAND      ${CMAKE_COMMAND} -P "${script}" test      "" after
+)
diff --git a/Tests/RunCMake/ExternalProject/RunCMakeTest.cmake b/Tests/RunCMake/ExternalProject/RunCMakeTest.cmake
index caaf0d2..0d1da26 100644
--- a/Tests/RunCMake/ExternalProject/RunCMakeTest.cmake
+++ b/Tests/RunCMake/ExternalProject/RunCMakeTest.cmake
@@ -29,6 +29,10 @@ endfunction()
 
 __ep_test_with_build(MultiCommand)
 
+set(RunCMake_TEST_OUTPUT_MERGE 1)
+__ep_test_with_build(PreserveEmptyArgs)
+set(RunCMake_TEST_OUTPUT_MERGE 0)
+
 # Output is not predictable enough to be able to verify it reliably
 # when using the various different Visual Studio generators
 if(NOT RunCMake_GENERATOR MATCHES "Visual Studio")
diff --git a/Tests/RunCMake/ExternalProject/countArgs.cmake b/Tests/RunCMake/ExternalProject/countArgs.cmake
new file mode 100644
index 0000000..ee6429a
--- /dev/null
+++ b/Tests/RunCMake/ExternalProject/countArgs.cmake
@@ -0,0 +1,5 @@
+message(STATUS "Number of arguments for ${CMAKE_ARGV3}: ${CMAKE_ARGC}")
+math(EXPR last "${CMAKE_ARGC} - 1")
+foreach(n RANGE 4 ${last})
+  message(STATUS "${CMAKE_ARGV3} argument ${n}: '${CMAKE_ARGV${n}}'")
+endforeach()