Check for a matching bext version branch before cloning RELEASE

Avoid older releases pulling dependencies that might be too new or
changed by first looking for a bext branch that matches the current
BRL-CAD release.

misc/CMake/BRLCAD_EXT_Setup.cmake

@@ -46,6 +46,16 @@ function(brlcad_ext_setup)
  set(BEXT_SRC_CLEANUP FALSE)
  if (NOT DEFINED BRLCAD_EXT_SOURCE_DIR)
 
+ # In most cases we'll need to know the current version
+ file(READ ${CMAKE_SOURCE_DIR}/include/conf/MAJOR VMAJOR)
+ file(READ ${CMAKE_SOURCE_DIR}/include/conf/MINOR VMINOR)
+ file(READ ${CMAKE_SOURCE_DIR}/include/conf/PATCH VPATCH)
+ string(STRIP "${VMAJOR}" VMAJOR)
+ string(STRIP "${VMINOR}" VMINOR)
+ string(STRIP "${VPATCH}" VPATCH)
+ set(BRLCAD_REL "rel-${VMAJOR}-${VMINOR}-${VPATCH}")
+
+
  # If we have a bext copy in src/bext, use that.
  if (EXISTS "${CMAKE_SOURCE_DIR}/src/bext/README.md")
 
@@ -96,15 +106,8 @@ function(brlcad_ext_setup)
  # Development branches should be keeping up with bext RELEASE, but a
  # tagged release should point to its equivalent rel-X-Y-Z in bext.
  # In case this is a release, also check for that SHA1
- file(READ ${CMAKE_SOURCE_DIR}/include/conf/MAJOR VMAJOR)
- file(READ ${CMAKE_SOURCE_DIR}/include/conf/MINOR VMINOR)
- file(READ ${CMAKE_SOURCE_DIR}/include/conf/PATCH VPATCH)
- string(STRIP "${VMAJOR}" VMAJOR)
- string(STRIP "${VMINOR}" VMINOR)
- string(STRIP "${VPATCH}" VPATCH)
- set(REL "rel-${VMAJOR}-${VMINOR}-${VPATCH}")
  execute_process(
- COMMAND ${GIT_EXEC} ls-remote https://github.com/BRL-CAD/bext.git ${REL}
+ COMMAND ${GIT_EXEC} ls-remote https://github.com/BRL-CAD/bext.git ${BRLCAD_REL}
  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
  RESULT_VARIABLE LS_REL_STATUS
  OUTPUT_VARIABLE LS_REL_STR
@@ -128,17 +131,27 @@ function(brlcad_ext_setup)
 
  # If not, next up is a bext dir in the build directory. If
  # one doesn't already exist, try to clone it
-
- # TODO - need to use the ls-remote trick from above to first check for a branch
- # in bext that corresponds to the current release - if we have one, we should
- # be using that. As it stands, old releases will pull the very latest release's
- # dependencies with this clone, which may not work. We want this only if there
- # isn't a matching versioned release branch.
  set(BRLCAD_EXT_SOURCE_DIR ${CMAKE_CURRENT_BINARY_DIR}/bext)
  if (NOT EXISTS ${BRLCAD_EXT_SOURCE_DIR})
+ # Development branches should be keeping up with bext RELEASE, but a
+ # tagged release should clone its equivalent rel-X-Y-Z in bext.
+ # Check for a matching branch in bext
+ execute_process(
+ COMMAND ${GIT_EXEC} ls-remote https://github.com/BRL-CAD/bext.git ${BRLCAD_REL}
+ WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+ RESULT_VARIABLE LS_REL_STATUS
+ OUTPUT_VARIABLE LS_REL_STR
+ ERROR_VARIABLE LS_REL_STR
+ )
+ if (NOT LS_REL_STATUS AND LS_REL_STR)
+ set(CBRANCH "${BRLCAD_REL}")
+ else (NOT LS_REL_STATUS AND LS_REL_STR)
+ set(CBRANCH "RELEASE")
+ endif (NOT LS_REL_STATUS AND LS_REL_STR)
+
  find_program(GIT_EXEC git REQUIRED)
  execute_process(
- COMMAND ${GIT_EXEC} clone -b RELEASE https://github.com/BRL-CAD/bext.git
+ COMMAND ${GIT_EXEC} clone -b ${CBRANCH} https://github.com/BRL-CAD/bext.git
  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
  )
  set(BEXT_SRC_CLEANUP TRUE)