replace the fancy python script with a simple patch

Author: dconeybe

cmake/external/firestore.cmake

@@ -18,14 +18,6 @@ if(TARGET firestore)
   return()
 endif()
 
-if(${CMAKE_VERSION} VERSION_LESS "3.12")
-  include(FindPythonInterp)
-  set(MY_PYTHON_EXECUTABLE "${PYTHON_EXECUTABLE}")
-else()
-  find_package(Python3 COMPONENTS Interpreter REQUIRED)
-  set(MY_PYTHON_EXECUTABLE "${Python3_EXECUTABLE}")
-endif()
-
 # If the format of the line below changes, then be sure to update
 # https://github.com/firebase/firebase-cpp-sdk/blob/fd054fa016/.github/workflows/update-dependencies.yml#L81
 set(version CocoaPods-9.1.0)
@@ -46,11 +38,7 @@ function(GetReleasedDep)
     BUILD_COMMAND ""
     INSTALL_COMMAND ""
     TEST_COMMAND ""
-    PATCH_COMMAND
-      ${MY_PYTHON_EXECUTABLE}
-      ${CMAKE_CURRENT_LIST_DIR}/firestore_patch.py
-      --leveldb-version-from
-      ${CMAKE_CURRENT_LIST_DIR}/leveldb.cmake
+    PATCH_COMMAND patch -Np1 -i ${CMAKE_CURRENT_LIST_DIR}/firestore.patch.txt
     HTTP_HEADER "${EXTERNAL_PROJECT_HTTP_HEADER}"
     )
 endfunction()
@@ -71,11 +59,7 @@ function(GetTag t)
     BUILD_COMMAND ""
     INSTALL_COMMAND ""
     TEST_COMMAND ""
-    PATCH_COMMAND
-      ${MY_PYTHON_EXECUTABLE}
-      ${CMAKE_CURRENT_LIST_DIR}/firestore_patch.py
-      --leveldb-version-from
-      ${CMAKE_CURRENT_LIST_DIR}/leveldb.cmake
+    PATCH_COMMAND patch -Np1 -i ${CMAKE_CURRENT_LIST_DIR}/firestore.patch.txt
     HTTP_HEADER "${EXTERNAL_PROJECT_HTTP_HEADER}"
     )
 endfunction()

cmake/external/firestore.patch.txt

@@ -0,0 +1,25 @@
+diff --git a/cmake/external/leveldb.cmake b/cmake/external/leveldb.cmake
+index 920bf2928..c5c9cc7ee 100644
+--- a/cmake/external/leveldb.cmake
++++ b/cmake/external/leveldb.cmake
+@@ -24,7 +24,10 @@ if(TARGET leveldb)
+   return()
+ endif()
+ 
+-set(version 1.22)
++# This version must be kept in sync with cmake/external/leveldb.cmake
++# in the firebase-cpp-sdk. If this version ever changes then make sure
++# to update leveldb.cmake in the firebase-cpp-sdk accordingly.
++set(version 1.23)
+ 
+ ExternalProject_Get_property(snappy SOURCE_DIR)
+ set(snappy_source_dir "${SOURCE_DIR}")
+@@ -39,7 +42,7 @@ ExternalProject_Add(
+   DOWNLOAD_DIR ${FIREBASE_DOWNLOAD_DIR}
+   DOWNLOAD_NAME leveldb-${version}.tar.gz
+   URL https://github.com/google/leveldb/archive/${version}.tar.gz
+-  URL_HASH SHA256=55423cac9e3306f4a9502c738a001e4a339d1a38ffbee7572d4a07d5d63949b2
++  URL_HASH SHA256=9a37f8a6174f09bd622bc723b55881dc541cd50747cbd08831c2a82d620f6d76
+ 
+   PREFIX ${PROJECT_BINARY_DIR}
+