CMake: Replace custom FindSqlite3 with FindSQLite3 built-in

CMakeLists.txt

@@ -176,15 +176,22 @@ if(NOT EXE_SQLITE3)
   message(SEND_ERROR "sqlite3 binary not found!")
 endif()
 
-find_package(Sqlite3 REQUIRED)
-if(NOT SQLITE3_FOUND)
-  message(SEND_ERROR "sqlite3 dependency not found!")
+# Deprecated variables since PROJ 9.4.0
+if(DEFINED SQLITE3_INCLUDE_DIR)
+  message(DEPRECATION "Use SQLite3_INCLUDE_DIR instead of SQLITE3_INCLUDE_DIR")
+  set(SQLite3_INCLUDE_DIR ${SQLITE3_INCLUDE_DIR})
 endif()
+if(DEFINED SQLITE3_LIBRARY)
+  message(DEPRECATION "Use SQLite3_LIBRARY instead of SQLITE3_LIBRARY")
+  set(SQLite3_LIBRARY ${SQLITE3_LIBRARY})
+endif()
+
+find_package(SQLite3 REQUIRED)
 
 # Would build and run with older versions, but with horrible performance
 # See https://github.com/OSGeo/PROJ/issues/1718
-if("${SQLITE3_VERSION}" VERSION_LESS "3.11")
-  message(SEND_ERROR "sqlite3 >= 3.11 required!")
+if(SQLite3_VERSION VERSION_LESS "3.11")
+  message(SEND_ERROR "SQLite3 >= 3.11 required!")
 endif()
 
 ################################################################################

docs/source/install.rst

@@ -173,12 +173,8 @@ On Windows, one may need to specify generator::
 
     cmake -G "Visual Studio 15 2017" ..
 
-If the SQLite3 dependency is installed in a custom location, specify the
-paths to the include directory and the library::
-
-    cmake -DSQLITE3_INCLUDE_DIR=/opt/SQLite/include -DSQLITE3_LIBRARY=/opt/SQLite/lib/libsqlite3.so ..
-
-Alternatively, the custom prefix for SQLite3 can be specified::
+If the SQLite3 dependency is installed in a custom location, specify
+:option:`CMAKE_PREFIX_PATH`::
 
     cmake -DCMAKE_PREFIX_PATH=/opt/SQLite ..
 
@@ -315,6 +311,12 @@ All cached entries can be viewed using ``cmake -LAH`` from a build directory.
     :envvar:`OSGEO4W_ROOT` (if set), otherwise is ``c:/OSGeo4W``.
     Default for Unix-like is ``/usr/local/``.
 
+.. option:: CMAKE_PREFIX_PATH
+
+    `CMake variable
+    <https://cmake.org/cmake/help/latest/variable/CMAKE_PREFIX_PATH.html>`_
+    used to specify installation prefixes for SQLite3 and other dependencies.
+
 .. option:: CMAKE_UNITY_BUILD=OFF
 
     .. versionadded:: 9.4
@@ -341,14 +343,10 @@ All cached entries can be viewed using ``cmake -LAH`` from a build directory.
 
     Path to an ``sqlite3`` or ``sqlite3.exe`` executable.
 
-.. option:: SQLITE3_INCLUDE_DIR
-
-    Path to an include directory with the ``sqlite3.h`` header file.
-
-.. option:: SQLITE3_LIBRARY
-
-    Path to a shared or static library file, such as ``sqlite3.dll``,
-    ``libsqlite3.so``, ``sqlite3.lib`` or other name.
+.. deprecated:: 9.4.0
+    ``SQLITE3_INCLUDE_DIR`` and ``SQLITE3_LIBRARY`` should be replaced with
+    ``SQLite3_INCLUDE_DIR`` and ``SQLite3_LIBRARY``, respectively.
+    Users may also consider :option:`CMAKE_PREFIX_PATH` instead.
 
 .. option:: ENABLE_CURL=ON
 

test/unit/CMakeLists.txt

@@ -64,7 +64,7 @@ endif()  # USE_EXTERNAL_GTEST
 #
 
 include_directories(${PROJ_SOURCE_DIR}/include)
-include_directories(${SQLITE3_INCLUDE_DIR})
+
 # Add the directory containing proj_config.h
 include_directories(${PROJ_BINARY_DIR}/src)
 
@@ -140,8 +140,8 @@ set_property(SOURCE ${PROJ_TEST_CPP_API_SOURCES} PROPERTY SKIP_UNITY_BUILD_INCLU
 
 target_link_libraries(proj_test_cpp_api
   PRIVATE GTest::gtest
-  PRIVATE ${PROJ_LIBRARIES}
-  PRIVATE ${SQLITE3_LIBRARY})
+  PRIVATE SQLite::SQLite3
+  PRIVATE ${PROJ_LIBRARIES})
 add_test(NAME proj_test_cpp_api COMMAND proj_test_cpp_api)
 set_property(TEST proj_test_cpp_api
   PROPERTY ENVIRONMENT ${PROJ_TEST_ENVIRONMENT})
@@ -172,8 +172,8 @@ if(CURL_ENABLED)
 endif()
 target_link_libraries(test_network
   PRIVATE GTest::gtest
-  PRIVATE ${PROJ_LIBRARIES}
-  PRIVATE ${SQLITE3_LIBRARY})
+  PRIVATE SQLite::SQLite3
+  PRIVATE ${PROJ_LIBRARIES})
 if(TIFF_ENABLED)
 add_test(NAME test_network COMMAND test_network)
 set_property(TEST test_network