Add package lock (#121)

* add package lock creation

* change target name

* fix cpm_export_variables

* add test

* fix git repo detection addition

* remove test package lock from git

* add link to package lock wiki

* add CPMGetPackage

test/unit/modules.cmake

@@ -6,7 +6,7 @@ set(TEST_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR}/modules)
 
 function(initProjectWithDependency TEST_DEPENDENCY_NAME)
   configure_package_config_file(
-    "${CMAKE_CURRENT_LIST_DIR}/test_project/CMakeLists.txt.in"
+    "${CMAKE_CURRENT_LIST_DIR}/test_project/ModuleCMakeLists.txt.in"
     "${CMAKE_CURRENT_LIST_DIR}/test_project/CMakeLists.txt"
     INSTALL_DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/junk
   )

test/unit/package-lock.cmake

@@ -0,0 +1,48 @@
+
+include(CMakePackageConfigHelpers)
+include(${CPM_PATH}/testing.cmake)
+
+set(TEST_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR}/package-lock)
+
+function(configureWithDeclare DECLARE_DEPENDENCY)
+  execute_process(COMMAND ${CMAKE_COMMAND} -E rm -rf ${TEST_BUILD_DIR})
+
+  if (DECLARE_DEPENDENCY)
+    set(PREPARE_CODE "CPMDeclarePackage(Dependency
+      NAME Dependency 
+      SOURCE_DIR ${CMAKE_CURRENT_LIST_DIR}/test_project/dependency
+    )")
+  else()
+    set(PREPARE_CODE "")
+  endif()
+
+  configure_package_config_file(
+    "${CMAKE_CURRENT_LIST_DIR}/test_project/PackageLockCMakeLists.txt.in"
+    "${CMAKE_CURRENT_LIST_DIR}/test_project/CMakeLists.txt"
+    INSTALL_DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/junk
+  )
+
+  execute_process(
+    COMMAND ${CMAKE_COMMAND} -H${CMAKE_CURRENT_LIST_DIR}/test_project -B${TEST_BUILD_DIR}
+    RESULT_VARIABLE ret
+  )
+
+  ASSERT_EQUAL(${ret} "0")
+endfunction()
+
+function(updatePackageLock)
+  execute_process(
+    COMMAND ${CMAKE_COMMAND} --build ${TEST_BUILD_DIR} --target cpm-update-package-lock
+    RESULT_VARIABLE ret
+  )
+
+  ASSERT_EQUAL(${ret} "0")
+endfunction()
+
+execute_process(COMMAND ${CMAKE_COMMAND} -E rm -f ${CMAKE_CURRENT_LIST_DIR}/test_project/package-lock.cmake)
+configureWithDeclare(YES)
+ASSERT_NOT_EXISTS(${CMAKE_CURRENT_LIST_DIR}/test_project/package-lock.cmake)
+updatePackageLock()
+ASSERT_EXISTS(${CMAKE_CURRENT_LIST_DIR}/test_project/package-lock.cmake)
+configureWithDeclare(NO)
+

test/unit/source_dir.cmake

@@ -7,7 +7,7 @@ set(TEST_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR}/source_dir)
 set(TEST_DEPENDENCY_NAME Dependency)
 
 configure_package_config_file(
-  "${CMAKE_CURRENT_LIST_DIR}/test_project/CMakeLists.txt.in"
+  "${CMAKE_CURRENT_LIST_DIR}/test_project/ModuleCMakeLists.txt.in"
   "${CMAKE_CURRENT_LIST_DIR}/test_project/CMakeLists.txt"
   INSTALL_DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/junk
 )

test/unit/test_project/.gitignore

@@ -1 +1,2 @@
-/CMakeLists.txt
+/CMakeLists.txt
+/package-lock.cmake

test/unit/test_project/ModuleCMakeLists.txt.in

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
 
-project(CPMExampleCatch2)
+project(CPMTest)
 
 # ---- Options ----
 

test/unit/test_project/PackageLockCMakeLists.txt.in

@@ -0,0 +1,20 @@
+cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
+
+project(CPMTest)
+
+# ---- Options ----
+
+option(ENABLE_TEST_COVERAGE "Enable test coverage" OFF)
+
+# ---- Dependencies ----
+
+include(@CPM_PATH@/CPM.cmake)
+CPMUsePackageLock(package-lock.cmake)
+
+@PREPARE_CODE@
+
+CPMGetPackage(Dependency)
+
+# ---- Call dependency method to validate correct addition of directory ----
+
+dependency_function()