Teach ctest_update about Git submodules

Git does not automatically checkout the matching version of a submodule
when it checks out a new version of the parent project in the work tree.
If the submodule reference changed in the parent project then we were
reporting the submodule path as a local modification.  Work around the
problem in ctest_update using "git submodule update" after "git pull".
For projects with no submodules this is a no-op.  See issue #10662.
Also add a submodule to the test project for CTest.UpdateGIT to test the
work-around.

2 files changed, 71 insertions, 2 deletions

diff --git a/Tests/CTestUpdateCommon.cmake b/Tests/CTestUpdateCommon.cmake
index 94c37fe75b..266f4b3bd5 100644
--- a/Tests/CTestUpdateCommon.cmake
+++ b/Tests/CTestUpdateCommon.cmake
@@ -41,8 +41,8 @@ function(check_updates build)
 
   # Compare expected and actual entries
   set(EXTRA "${UPDATE_XML_ENTRIES}")
-  list(REMOVE_ITEM EXTRA ${ARGN} ${UPDATE_MAYBE})
-  set(MISSING "${ARGN}")
+  list(REMOVE_ITEM EXTRA ${ARGN} ${UPDATE_EXTRA} ${UPDATE_MAYBE})
+  set(MISSING "${ARGN}" ${UPDATE_EXTRA})
   list(REMOVE_ITEM MISSING ${UPDATE_XML_ENTRIES})
 
   if(NOT UPDATE_NOT_GLOBAL)
diff --git a/Tests/CTestUpdateGIT.cmake.in b/Tests/CTestUpdateGIT.cmake.in
index c721bb4e6d..f0a577084a 100644
--- a/Tests/CTestUpdateGIT.cmake.in
+++ b/Tests/CTestUpdateGIT.cmake.in
@@ -5,6 +5,7 @@
 # Test in a directory next to this script.
 get_filename_component(TOP "${CMAKE_CURRENT_LIST_FILE}" PATH)
 set(TOP "${TOP}/@CTestUpdateGIT_DIR@")
+set(UPDATE_EXTRA Updated{module})
 
 # Include code common to all update tests.
 include("@CMAKE_CURRENT_SOURCE_DIR@/CTestUpdateCommon.cmake")
@@ -42,6 +43,35 @@ run_child(
 file(REMOVE_RECURSE ${TOP}/repo.git/hooks)
 set(REPO file://${TOP}/repo.git)
 
+# Create submodule repository.
+message("Creating submodule...")
+file(MAKE_DIRECTORY ${TOP}/module.git)
+run_child(
+  WORKING_DIRECTORY ${TOP}/module.git
+  COMMAND ${GIT} --bare init
+  )
+file(REMOVE_RECURSE ${TOP}/module.git/hooks)
+set(MOD_REPO file://${TOP}/module.git)
+create_content(module)
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} init
+  )
+file(REMOVE_RECURSE ${TOP}/module/.git/hooks)
+file(APPEND ${TOP}/module/.git/config "
+[remote \"origin\"]
+\turl = ${MOD_REPO}
+\tfetch = +refs/heads/*:refs/remotes/origin/*
+${AUTHOR_CONFIG}")
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} add .
+  )
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} commit -m "Initial content"
+  )
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} push origin master:refs/heads/master
+  )
+
 #-----------------------------------------------------------------------------
 # Import initial content into the repository.
 message("Importing content...")
@@ -61,6 +91,9 @@ run_child(WORKING_DIRECTORY ${TOP}/import
   COMMAND ${GIT} add .
   )
 run_child(WORKING_DIRECTORY ${TOP}/import
+  COMMAND ${GIT} submodule add ${MOD_REPO} module
+  )
+run_child(WORKING_DIRECTORY ${TOP}/import
   COMMAND ${GIT} commit -m "Initial content"
   )
 run_child(WORKING_DIRECTORY ${TOP}/import
@@ -68,6 +101,19 @@ run_child(WORKING_DIRECTORY ${TOP}/import
   )
 
 #-----------------------------------------------------------------------------
+# Modify the submodule.
+change_content(module)
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} add -u
+  )
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} commit -m "Changed content"
+  )
+run_child(WORKING_DIRECTORY ${TOP}/module
+  COMMAND ${GIT} push origin master:refs/heads/master
+  )
+
+#-----------------------------------------------------------------------------
 # Create a working tree.
 message("Checking out revision 1...")
 run_child(
@@ -76,6 +122,14 @@ run_child(
   )
 file(REMOVE_RECURSE ${TOP}/user-source/.git/hooks)
 file(APPEND ${TOP}/user-source/.git/config "${AUTHOR_CONFIG}")
+run_child(
+  WORKING_DIRECTORY ${TOP}/user-source
+  COMMAND ${GIT} submodule init
+  )
+run_child(
+  WORKING_DIRECTORY ${TOP}/user-source
+  COMMAND ${GIT} submodule update
+  )
 
 #-----------------------------------------------------------------------------
 # Make changes in the working tree.
@@ -95,6 +149,9 @@ run_child(
   WORKING_DIRECTORY ${TOP}/user-source
   COMMAND ${GIT} rm ${files_removed}
   )
+run_child(WORKING_DIRECTORY ${TOP}/user-source/module
+  COMMAND ${GIT} checkout master
+  )
 run_child(
   WORKING_DIRECTORY ${TOP}/user-source
   COMMAND ${GIT} add -u
@@ -140,6 +197,10 @@ run_child(
   WORKING_DIRECTORY ${TOP}/user-source
   COMMAND ${GIT} reset --hard master~2
   )
+run_child(
+  WORKING_DIRECTORY ${TOP}/user-source
+  COMMAND ${GIT} submodule update
+  )
 
 # Make sure pull does not try to rebase (which does not work with
 # modified files) even if ~/.gitconfig sets "branch.master.rebase".
@@ -181,6 +242,14 @@ execute_process(
   WORKING_DIRECTORY \"${TOP}/dash-source\"
   COMMAND \"${GIT}\" reset --hard master~2
   )
+execute_process(
+  WORKING_DIRECTORY \"${TOP}/dash-source\"
+  COMMAND \"${GIT}\" submodule init
+  )
+execute_process(
+  WORKING_DIRECTORY \"${TOP}/dash-source\"
+  COMMAND \"${GIT}\" submodule update
+  )
 ")
 
 # Run the dashboard script with CTest.