Add FindGit module.

Use it from ExternalProject and the ExternalProject test's
CMakeLists file rather than having duplicate find_program calls.
Add logic so that we do not try to use *.cmd variants of git
programs when using the MSYS Makefiles generator. Should fix
the last remaining dashboard issue with the new ExternalProject
git support additions.

Also, correct minor problem regarding placement of the local git
repo during test execution. On clean builds, it was being placed
incorrectly because of the ../.. relative reference. Use an absolute
path to place the local git repo in the proper directory, and only
use the relative reference when referring to it.

Modules/ExternalProject.cmake

@@ -749,15 +749,14 @@ function(_ep_add_download_command name)
     set(cmd ${Subversion_SVN_EXECUTABLE} co ${svn_repository} ${svn_revision} ${src_name})
     list(APPEND depends ${stamp_dir}/${name}-svninfo.txt)
   elseif(git_repository)
-    find_program(git_EXECUTABLE NAMES git.cmd git eg.cmd eg DOC "git command line client")
-    mark_as_advanced(git_EXECUTABLE)
-    if(NOT git_EXECUTABLE)
+    find_package(Git)
+    if(NOT GIT_EXECUTABLE)
       message(FATAL_ERROR "error: could not find git for clone of ${name}")
     endif()
 
     # The git submodule update '--recursive' flag requires git >= v1.6.5
     #
-    _ep_get_git_version("${git_EXECUTABLE}" git_version)
+    _ep_get_git_version("${GIT_EXECUTABLE}" git_version)
     if(git_version VERSION_LESS 1.6.5)
       message(FATAL_ERROR "error: git version 1.6.5 or later required for 'git submodule update --recursive': git_version='${git_version}'")
     endif()
@@ -784,7 +783,7 @@ function(_ep_add_download_command name)
     # The script will delete the source directory and then call git clone.
     #
     _ep_write_gitclone_script(${tmp_dir}/${name}-gitclone.cmake ${source_dir}
-      ${git_EXECUTABLE} ${git_repository} ${git_tag} ${src_name} ${work_dir}
+      ${GIT_EXECUTABLE} ${git_repository} ${git_tag} ${src_name} ${work_dir}
       )
     set(comment "Performing download step (git clone) for '${name}'")
     set(cmd ${CMAKE_COMMAND} -P ${tmp_dir}/${name}-gitclone.cmake)
@@ -874,7 +873,7 @@ function(_ep_add_update_command name)
     set(cmd ${Subversion_SVN_EXECUTABLE} up ${svn_revision})
     set(always 1)
   elseif(git_repository)
-    if(NOT git_EXECUTABLE)
+    if(NOT GIT_EXECUTABLE)
       message(FATAL_ERROR "error: could not find git for fetch of ${name}")
     endif()
     set(work_dir ${source_dir})
@@ -883,9 +882,9 @@ function(_ep_add_update_command name)
     if(NOT git_tag)
       set(git_tag "master")
     endif()
-    set(cmd ${git_EXECUTABLE} fetch
-      COMMAND ${git_EXECUTABLE} checkout ${git_tag}
-      COMMAND ${git_EXECUTABLE} submodule update --recursive
+    set(cmd ${GIT_EXECUTABLE} fetch
+      COMMAND ${GIT_EXECUTABLE} checkout ${git_tag}
+      COMMAND ${GIT_EXECUTABLE} submodule update --recursive
       )
     set(always 1)
   endif()

Modules/FindGit.cmake

@@ -0,0 +1,46 @@
+# The module defines the following variables:
+#   GIT_EXECUTABLE - path to git command line client
+#   GIT_FOUND - true if the command line client was found
+# Example usage:
+#   find_package(Git)
+#   if(GIT_FOUND)
+#     message("git found: ${GIT_EXECUTABLE}")
+#   endif()
+
+#=============================================================================
+# Copyright 2010 Kitware, Inc.
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distributed this file outside of CMake, substitute the full
+#  License text for the above reference.)
+
+# Look for 'git' or 'eg' (easy git)
+#
+set(git_names git eg)
+
+# Prefer .cmd variants on Windows unless running in a Makefile
+# in the MSYS shell.
+#
+if(WIN32)
+  if(NOT CMAKE_GENERATOR MATCHES "MSYS")
+    set(git_names git.cmd git eg.cmd eg)
+  endif()
+endif()
+
+find_program(GIT_EXECUTABLE
+  NAMES ${git_names}
+  DOC "git command line client"
+  )
+mark_as_advanced(GIT_EXECUTABLE)
+
+# Handle the QUIETLY and REQUIRED arguments and set GIT_FOUND to TRUE if
+# all listed variables are TRUE
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Git DEFAULT_MSG GIT_EXECUTABLE)

Tests/ExternalProject/CMakeLists.txt

@@ -5,7 +5,7 @@ include(ExternalProject)
 
 find_package(CVS)
 find_package(Subversion)
-find_program(git_EXECUTABLE NAMES git.cmd git eg.cmd eg DOC "git command line client")
+find_package(Git)
 
 set(base "${CMAKE_BINARY_DIR}/CMakeExternals")
 set(binary_base "${base}/Build")
@@ -302,11 +302,11 @@ endif()
 
 set(do_git_tests 0)
 
-if(git_EXECUTABLE)
+if(GIT_EXECUTABLE)
   set(do_git_tests 1)
 
   execute_process(
-    COMMAND "${git_EXECUTABLE}" --version
+    COMMAND "${GIT_EXECUTABLE}" --version
     OUTPUT_VARIABLE ov
     OUTPUT_STRIP_TRAILING_WHITESPACE
     )
@@ -328,10 +328,10 @@ if(do_git_tests)
   #
   set(proj SetupLocalGITRepository)
   ExternalProject_Add(${proj}
-    SOURCE_DIR ${local_git_repo}
+    SOURCE_DIR ${CMAKE_CURRENT_BINARY_DIR}/LocalRepositories/GIT
     URL ${CMAKE_CURRENT_SOURCE_DIR}/gitrepo.tgz
     BUILD_COMMAND ""
-    CONFIGURE_COMMAND "${git_EXECUTABLE}" --version
+    CONFIGURE_COMMAND "${GIT_EXECUTABLE}" --version
     INSTALL_COMMAND ""
   )
 
@@ -444,4 +444,4 @@ message(STATUS "can_build_tutorial_step5='${can_build_tutorial_step5}'")
 message(STATUS "do_cvs_tests='${do_cvs_tests}'")
 message(STATUS "do_svn_tests='${do_svn_tests}'")
 message(STATUS "do_git_tests='${do_git_tests}'")
-message(STATUS "git_EXECUTABLE='${git_EXECUTABLE}'")
+message(STATUS "GIT_EXECUTABLE='${GIT_EXECUTABLE}'")