From 5fe036d9adc4147dbba0c35a4e855ad09b2e263b Mon Sep 17 00:00:00 2001
From: Saleem Abdulrasool <compnerd@compnerd.org>
Date: Tue, 19 Dec 2023 15:43:55 -0800
Subject: [PATCH] build: add an upgrade path for newer CMake

CMake 3.12 deprecated `FindPythonInterp`, and with CMake 3.27, were
obsoleted with CMP0148.  Add a version check and switch to the new
behaviour to allow building with newer releases.  When the minimum CMake
version is increased, we can look at dropping the compatibility path.
---
 test/CMakeLists.txt | 42 ++++++++++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 16 deletions(-)

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 5c07fb7b2..106d3a9fe 100755
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -3,11 +3,21 @@
 # By default, we run the spec tests only if python3 is available.
 # To require the spec tests, compile with -DSPEC_TESTS=1
 
-if (SPEC_TESTS)
-  find_package(PythonInterp 3 REQUIRED)
-else(SPEC_TESTS)
-  find_package(PythonInterp 3)
-endif(SPEC_TESTS)
+if(SPEC_TESTS)
+  set(PYTHON_REQUIRED REQUIRED)
+else()
+  set(PYTHON_REQUIRED)
+endif()
+
+if(CMAKE_VERSION VERSION_GREATER_EQUAL 3.12)
+  find_package(Python3 ${PYTHON_REQUIRED} COMPONENTS Interperter)
+else()
+  find_package(PythonInterp 3 ${PYTHON_REQUIRED})
+  set(Python_Interpreter_FOUND ${PYTHONINTERP_FOUND})
+  add_executable(Python::Interpreter IMPORTED)
+  set_target_properties(Python::Interpreter PROPERTIES
+    IMPORTED_LOCATION ${PYTHON_EXECUTABLE})
+endif()
 
 if (CMARK_SHARED OR CMARK_STATIC)
   add_test(NAME api_test COMMAND api_test)
@@ -23,58 +33,58 @@ else(WIN32)
   set(ROUNDTRIP "${CMAKE_CURRENT_SOURCE_DIR}/roundtrip.sh")
 endif(WIN32)
 
-IF (PYTHONINTERP_FOUND)
+IF (Python_Interpreter_FOUND)
 
   add_test(html_normalization
-    ${PYTHON_EXECUTABLE} "-m" "doctest"
+    $<Python::Interpreter> "-m" "doctest"
     "${CMAKE_CURRENT_SOURCE_DIR}/normalize.py"
     )
 
   if (CMARK_SHARED)
     add_test(spectest_library
-      ${PYTHON_EXECUTABLE} "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec"
+      $<Python::Interpreter> "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec"
       "${CMAKE_CURRENT_SOURCE_DIR}/spec.txt" "--library-dir" "${CMAKE_CURRENT_BINARY_DIR}/../src"
       )
 
     add_test(pathological_tests_library
-      ${PYTHON_EXECUTABLE} "${CMAKE_CURRENT_SOURCE_DIR}/pathological_tests.py"
+      $<Python::Interpreter> "${CMAKE_CURRENT_SOURCE_DIR}/pathological_tests.py"
       "--library-dir" "${CMAKE_CURRENT_BINARY_DIR}/../src"
       )
 
     add_test(roundtriptest_library
-      ${PYTHON_EXECUTABLE}
+      $<Python::Interpreter>
       "${CMAKE_CURRENT_SOURCE_DIR}/roundtrip_tests.py"
       "--spec" "${CMAKE_CURRENT_SOURCE_DIR}/spec.txt"
       "--library-dir" "${CMAKE_CURRENT_BINARY_DIR}/../src"
       )
 
     add_test(entity_library
-      ${PYTHON_EXECUTABLE}
+      $<Python::Interpreter>
       "${CMAKE_CURRENT_SOURCE_DIR}/entity_tests.py"
       "--library-dir" "${CMAKE_CURRENT_BINARY_DIR}/../src"
       )
   endif()
 
   add_test(spectest_executable
-    ${PYTHON_EXECUTABLE} "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec" "${CMAKE_CURRENT_SOURCE_DIR}/spec.txt" "--program" "${CMAKE_CURRENT_BINARY_DIR}/../src/cmark"
+    $<Python::Interpreter> "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec" "${CMAKE_CURRENT_SOURCE_DIR}/spec.txt" "--program" "${CMAKE_CURRENT_BINARY_DIR}/../src/cmark"
     )
 
   add_test(smartpuncttest_executable
-    ${PYTHON_EXECUTABLE} "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec" "${CMAKE_CURRENT_SOURCE_DIR}/smart_punct.txt" "--program" "${CMAKE_CURRENT_BINARY_DIR}/../src/cmark --smart"
+    $<Python::Interpreter> "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec" "${CMAKE_CURRENT_SOURCE_DIR}/smart_punct.txt" "--program" "${CMAKE_CURRENT_BINARY_DIR}/../src/cmark --smart"
     )
 
   add_test(regressiontest_executable
-    ${PYTHON_EXECUTABLE}
+    $<Python::Interpreter>
     "${CMAKE_CURRENT_SOURCE_DIR}/spec_tests.py" "--no-normalize" "--spec"
     "${CMAKE_CURRENT_SOURCE_DIR}/regression.txt" "--program"
     "${CMAKE_CURRENT_BINARY_DIR}/../src/cmark"
     )
 
-ELSE(PYTHONINTERP_FOUND)
+ELSE(Python_Interpreter_FOUND)
 
   message("\n*** A python 3 interpreter is required to run the spec tests.\n")
   add_test(skipping_spectests
     echo "Skipping spec tests, because no python 3 interpreter is available.")
 
-ENDIF(PYTHONINTERP_FOUND)
+ENDIF(Python_Interpreter_FOUND)