feat(api/c): PyImport_GetModule

Author: litlighilit

Python/pyimport/utils.nim

@@ -3,10 +3,19 @@ import ../[
   sysmodule_instance,
 ]
 import ../../Objects/[pyobject,
+  exceptions,
+  noneobject,
   stringobject,
   dictobject,
   moduleobject,
+  boolobjectImpl,
 ]
+import ../../Objects/pyobject_apis/attrs
+import ../../Include/internal/pycore_global_strings
+const HasImportLib = defined(npythonHasImportLib)  #TODO:imp
+when HasImportLib:
+  import ../../Objects/abstract/call
+  import ../coreconfig
 
 template import_add_moduleImpl(alreadyInAsgn): untyped{.dirty.} =
   var modu = sys.modules.getOptionalItem(name)
@@ -37,4 +46,62 @@ proc PyImport_AddModuleRef*(name: string): PyObject =
   let name_obj = newPyStr name
   PyImport_AddModuleRef name_obj
 
-proc import_get_module*(name: PyStrObject): PyObject = sys.modules.getOptionalItem name
+using name: PyStrObject
+proc import_get_module(name): PyObject = sys.modules.getOptionalItem name
+
+proc PyModuleSpec_IsInitializing*(spec: PyObject; res: var bool): PyBaseErrorObject =
+  ## Check if the "_initializing" attribute of the module spec is set to true.
+  res = false
+  if spec.isNil: return
+  var value: PyObject
+  var rc = PyObject_GetOptionalAttr(spec, pyId"_initializing", value)
+  if rc == Error:
+    return PyBaseErrorObject value
+  PyObject_IsTrue(value, res)
+
+proc import_ensure_initialized(modu: PyObject, name): PyBaseErrorObject =
+  #[ Optimization: only call _bootstrap._lock_unlock_module() if
+      __spec__._initializing is true.
+      NOTE: because of this, initializing must be set *before*
+      stuffing the new module in sys.modules.
+  ]#
+    #[ When -X importtime=2, print an import time entry even if an
+       imported module has already been loaded.
+     ]#
+  
+  proc done =
+    when HasImportLib:
+      if Py_GetConfig().import_time == 2:
+        IMPORT_TIME_HEADER(interp)
+        let import_level = FIND_AND_LOAD(interp).import_level
+        let s = name.asUTF8.align(import_level * 2)
+        errEchoCompat("import time: cached    | cached     | " & s)
+  template goto_done =
+    done()
+    return
+  var spec: PyObject
+  var rc: bool
+  let res = PyObject_GetOptionalAttr(modu, pyDUId(spec), spec)
+  case res
+  of Get:
+    retIfExc PyModuleSpec_IsInitializing(spec, rc)
+    if not rc: goto_done
+  of Missing:
+    goto_done
+  else:
+    return PyBaseErrorObject spec
+
+  # Wait until module is done importing.
+  when HasImportLib:
+    retIfExc callMethod(
+        IMPORTLIB(interp), pyId"_lock_unlock_module", name)
+
+  goto_done
+
+
+proc PyImport_GetModule*(name; res: var PyObject): PyBaseErrorObject =
+  res = import_get_module(name)
+  if res.isNil: return
+  retIfExc res
+  if res.isPyNone: return
+  retIfExc import_ensure_initialized(res, name)