You can now clear the active user for ownership history. See #1790.

src/blenderbim/blenderbim/bim/module/csv/operator.py

@@ -48,6 +48,7 @@ class RemoveCsvAttribute(bpy.types.Operator):
         context.scene.CsvProperties.csv_attributes.remove(self.index)
         return {"FINISHED"}
 
+
 class RemoveAllCsvAttributes(bpy.types.Operator):
     bl_idname = "bim.remove_all_csv_attributes"
     bl_label = "Remove all CSV Attributes"
@@ -57,6 +58,7 @@ class RemoveAllCsvAttributes(bpy.types.Operator):
         context.scene.CsvProperties.csv_attributes.clear()
         return {"FINISHED"}
 
+
 class ImportCsvAttributes(bpy.types.Operator):
     bl_idname = "bim.import_csv_attributes"
     bl_label = "Import CSV Attributes"
@@ -72,7 +74,7 @@ class ImportCsvAttributes(bpy.types.Operator):
         for attribute in csv_json:
             csv_attributes.add()
             csv_attributes[i].name = attribute
-            i +=1      
+            i += 1
 
         return {"FINISHED"}
 
@@ -80,6 +82,7 @@ class ImportCsvAttributes(bpy.types.Operator):
         context.window_manager.fileselect_add(self)
         return {"RUNNING_MODAL"}
 
+
 class ExportCsvAttributes(bpy.types.Operator):
     bl_idname = "bim.export_csv_attributes"
     bl_label = "Export CSV Attributes"
@@ -102,7 +105,8 @@ class ExportCsvAttributes(bpy.types.Operator):
         self.filepath = bpy.path.ensure_ext(bpy.data.filepath, ".json")
         WindowManager = context.window_manager
         WindowManager.fileselect_add(self)
-        return {"RUNNING_MODAL"}       
+        return {"RUNNING_MODAL"}
+
 
 class ExportIfcCsv(bpy.types.Operator):
     bl_idname = "bim.export_ifccsv"

src/blenderbim/blenderbim/bim/module/csv/ui.py

@@ -42,7 +42,7 @@ class BIM_PT_ifccsv(Panel):
             row = layout.row(align=True)
             row.prop(props, "csv_ifc_file")
             row.operator("bim.select_csv_ifc_file", icon="FILE_FOLDER", text="")
-    
+
         row = layout.row(align=True)
         row.prop(props, "ifc_selector")
         row.operator("bim.eyedrop_ifccsv", icon="EYEDROPPER", text="")
@@ -66,8 +66,8 @@ class BIM_PT_ifccsv(Panel):
             row.operator("bim.remove_all_csv_attributes", icon="CANCEL", text="")
             row = layout.row()
             row.operator("bim.export_csv_attributes", icon="EXPORT", text="Create Template")
-        
+
-        layout.separator()   
+        layout.separator()
 
         row = layout.row(align=True)
         row.prop(props, "csv_delimiter")

src/blenderbim/blenderbim/bim/module/owner/__init__.py

@@ -27,6 +27,7 @@ classes = (
     operator.AddPersonAndOrganisation,
     operator.AddPersonAttribute,
     operator.AddRole,
+    operator.ClearUser,
     operator.DisableEditingAddress,
     operator.DisableEditingOrganisation,
     operator.DisableEditingPerson,

src/blenderbim/blenderbim/bim/module/owner/operator.py

@@ -292,9 +292,19 @@ class RemovePersonAndOrganisation(bpy.types.Operator, Operator):
 
 class SetUser(bpy.types.Operator, Operator):
     bl_idname = "bim.set_user"
-    bl_label = "set_user"
+    bl_label = "Set User"
     bl_options = {"REGISTER", "UNDO"}
     user: bpy.props.IntProperty()
 
     def _execute(self, context):
         core.set_user(tool.Owner, user=tool.Ifc.get().by_id(self.user))
+
+
+class ClearUser(bpy.types.Operator, Operator):
+    bl_idname = "bim.clear_user"
+    bl_label = "Clear User"
+    bl_options = {"REGISTER", "UNDO"}
+    user: bpy.props.IntProperty()
+
+    def _execute(self, context):
+        core.clear_user(tool.Owner)

src/blenderbim/blenderbim/bim/module/owner/ui.py

@@ -218,8 +218,9 @@ class BIM_PT_owner(bpy.types.Panel):
             row = self.layout.row(align=True)
             if user["is_active"]:
                 row.label(text=user["label"], icon="USER")
+                row.operator("bim.clear_user", icon="KEYFRAME", text="").user = user["id"]
             else:
                 row.label(text=user["label"])
-            row.operator("bim.set_user", icon="KEYFRAME_HLT", text="").user = user["id"]
+                row.operator("bim.set_user", icon="KEYFRAME_HLT", text="").user = user["id"]
             op = row.operator("bim.remove_person_and_organisation", icon="X", text="")
             op.person_and_organisation = user["id"]

src/blenderbim/blenderbim/core/owner.py

@@ -139,3 +139,7 @@ def set_user(owner, user=None):
 
 def get_user(owner):
     return owner.get_user()
+
+
+def clear_user(owner):
+    owner.clear_user()

src/blenderbim/blenderbim/tool/ifc.py

@@ -37,7 +37,8 @@ class Ifc(blenderbim.core.tool.Ifc):
 
     @classmethod
     def get_schema(cls):
-        return IfcStore.get_file().schema
+        if IfcStore.get_file():
+            return IfcStore.get_file().schema
 
     @classmethod
     def get_entity(cls, obj):

src/blenderbim/blenderbim/tool/owner.py

@@ -30,6 +30,10 @@ class Owner(blenderbim.core.tool.Owner):
     def get_user(cls):
         if bpy.context.scene.BIMOwnerProperties.active_user_id:
             return tool.Ifc.get().by_id(bpy.context.scene.BIMOwnerProperties.active_user_id)
+        elif tool.Ifc.get_schema() == "IFC2X3":
+            users = tool.Ifc.get().by_type("IfcPersonAndOrganization")
+            if users:
+                return users[0]
 
     @classmethod
     def clear_user(cls):

src/blenderbim/test/bim/feature/owner.feature

@@ -233,3 +233,8 @@ Scenario: Set user
     And the variable "user" is "{ifc}.by_type('IfcPersonAndOrganization')[0].id()"
     And I press "bim.set_user(user={user})"
     Then nothing happens
+
+Scenario: Clear user
+    Given an empty IFC project
+    When I press "bim.clear_user(user={user})"
+    Then nothing happens

src/blenderbim/test/core/test_owner.py

@@ -219,3 +219,9 @@ class TestGetUser:
     def test_run(self, owner):
         owner.get_user().should_be_called().will_return("person_and_organisation")
         assert subject.get_user(owner) == "person_and_organisation"
+
+
+class TestClearUser:
+    def test_run(self, owner):
+        owner.clear_user().should_be_called()
+        subject.clear_user(owner)

src/blenderbim/test/tool/test_owner.py

@@ -45,6 +45,16 @@ class TestGetUser(test.bim.bootstrap.NewFile):
         user = tool.Ifc.get().by_type("IfcPersonAndOrganization")[0]
         assert subject.get_user() == user
 
+    def test_falling_back_to_any_available_user_ifc2x3(self):
+        assert subject.get_user() is None
+        ifc = ifcopenshell.file(schema="IFC2X3")
+        tool.Ifc.set(ifc)
+        user = ifc.createIfcPersonAndOrganization()
+        assert subject.get_user() == user
+        user2 = ifc.createIfcPersonAndOrganization()
+        subject.set_user(user2)
+        assert subject.get_user() == user2
+
 
 class TestClearUser(test.bim.bootstrap.NewFile):
     def test_run(self):