Add methods LuaRuntime.gccollect() and LuaRuntime.nogc() to control t…

…he Lua garbage collector.

CHANGES.rst

@@ -1,6 +1,12 @@
 Lupa change log
 ===============
 
+2.2 (2024-??-??)
+----------------
+
+* A new method ``LuaRuntime.gc()`` was added to control the Lua garbage collector.
+
+
 2.1 (2024-03-24)
 ----------------
 

lupa/_lupa.pyx

@@ -545,6 +545,23 @@ cdef class LuaRuntime:
  finally:
  unlock_runtime(self)
 
+ def nogc(self):
+ """
+ Return a context manager that temporarily disables the Lua garbage collector.
+ """
+ return _LuaNoGC(self)
+
+ def gccollect(self):
+ """
+ Run a full pass of the Lua garbage collector.
+ """
+ assert self._state is not NULL
+ cdef lua_State *L = self._state
+ lock_runtime(self)
+ # Pass third argument for compatibility with Lua 5.[123].
+ lua.lua_gc(L, lua.LUA_GCCOLLECT, <int> 0)
+ unlock_runtime(self)
+
  def set_max_memory(self, size_t max_memory, total=False):
  """Set maximum allowed memory for this LuaRuntime.
 
@@ -644,6 +661,37 @@ cdef class LuaRuntime:
  return 0 # nothing left to return on the stack
 
 
+@cython.internal
+cdef class _LuaNoGC:
+ """
+ A context manager that temporarily disables the Lua garbage collector.
+ """
+ cdef LuaRuntime _runtime
+
+ def __cinit__(self, LuaRuntime runtime not None):
+ self._runtime = runtime
+
+ def __enter__(self):
+ if self._runtime is None:
+ return # e.g. system teardown
+ assert self._runtime._state is not NULL
+ cdef lua_State *L = self._runtime._state
+ lock_runtime(self._runtime)
+ # Pass third argument for compatibility with Lua 5.[123].
+ lua.lua_gc(L, lua.LUA_GCSTOP, <int> 0)
+ unlock_runtime(self._runtime)
+
+ def __exit__(self, *exc):
+ if self._runtime is None:
+ return # e.g. system teardown
+ assert self._runtime._state is not NULL
+ cdef lua_State *L = self._runtime._state
+ lock_runtime(self._runtime)
+ # Pass third argument for compatibility with Lua 5.[123].
+ lua.lua_gc(L, lua.LUA_GCRESTART, <int> 0)
+ unlock_runtime(self._runtime)
+
+
 ################################################################################
 # decorators for calling Python functions with keyword (named) arguments
 # from Lua scripts

lupa/tests/test.py

@@ -120,6 +120,20 @@ def test_lua_implementation(self):
  self.assertTrue(lua_implementation.startswith("Lua"), lua_implementation)
  self.assertTrue(lua_implementation.split()[0] in ("Lua", "LuaJIT"), lua_implementation)
 
+ def test_lua_gccollect(self):
+ self.lua.gccollect()
+
+ def test_lua_nogc(self):
+ if self.lua.lua_version >= (5,2):
+ self.assertTrue(self.lua.eval('collectgarbage("isrunning")'))
+
+ with self.lua.nogc():
+ if self.lua.lua_version >= (5,2):
+ self.assertFalse(self.lua.eval('collectgarbage("isrunning")'))
+
+ if self.lua.lua_version >= (5,2):
+ self.assertTrue(self.lua.eval('collectgarbage("isrunning")'))
+
  def test_eval(self):
  self.assertEqual(2, self.lua.eval('1+1'))