Implement lightweight Gherkin testing for full stack tests

src/blenderbim/test/bim/bootstrap.py

@@ -17,12 +17,109 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 
+import re
 import bpy
 import pytest
 from blenderbim.bim.ifc import IfcStore
 
+
 class NewFile:
     @pytest.fixture(autouse=True)
     def setup(self):
         IfcStore.purge()
         bpy.ops.wm.read_homefile(app_template="")
+
+
+def scenario(function):
+    def subfunction(self):
+        run(function(self))
+
+    return subfunction
+
+
+def an_empty_ifc_project():
+    bpy.ops.bim.create_project()
+
+
+def i_add_a_cube():
+    bpy.ops.mesh.primitive_cube_add()
+
+
+def the_object_named_name_is_selected(name):
+    obj = bpy.context.scene.objects.get(name)
+    if not obj:
+        assert False, 'The object "{name}" could not be selected'
+    bpy.ops.object.select_all(action="DESELECT")
+    bpy.context.view_layer.objects.active = obj
+    obj.select_set(True)
+
+
+def i_select_value_in_prop(value, prop):
+    exec(f'bpy.context.{prop} = "{value}"')
+
+
+def i_press_operator(operator):
+    exec(f"bpy.ops.{operator}()")
+
+
+def the_object_named_name_exists(name):
+    obj = bpy.data.objects.get(name)
+    if not obj:
+        assert False, f'The object "{name}" does not exist'
+    return obj
+
+
+def an_ifc_file_exists():
+    ifc = IfcStore.get_file()
+    if not ifc:
+        assert False, "No IFC file is available"
+    return ifc
+
+
+def the_object_named_name_is_an_ifc_class(name, ifc_class):
+    ifc = an_ifc_file_exists()
+    element = ifc.by_id(the_object_named_name_exists(name).BIMObjectProperties.ifc_definition_id)
+    assert element.is_a(ifc_class), f'Object "{name}" is a {element.is_a()}'
+
+
+definitions = {
+    "an empty IFC project": an_empty_ifc_project,
+    "I add a cube": i_add_a_cube,
+    'the object named "(.*)" is selected': the_object_named_name_is_selected,
+    'I select "(.*)" in "(.*)"': i_select_value_in_prop,
+    'I press "(.*)"': i_press_operator,
+    'the object named "(.*)" is an "(.*)"': the_object_named_name_is_an_ifc_class,
+    "an IFC file exists": an_ifc_file_exists,
+}
+
+
+# Super lightweight Gherkin implementation
+def run(scenario):
+    for line in scenario.split("\n"):
+        line = line.strip()
+        if not line:
+            continue
+        match = None
+        for definition, callback in definitions.items():
+            match = re.search(definition, line)
+            if match:
+                try:
+                    callback(*match.groups())
+                except AssertionError as e:
+                    assert False, f"Failed: {line}, with error: {e}"
+                break
+        if not match:
+            assert False, f"Definition not implemented: {line}"
+    return True
+
+
+def run_debug(scenario, blend_filepath=None):
+    try:
+        result = run(scenario)
+    except Exception as e:
+        if blend_filepath:
+            bpy.ops.wm.save_as_mainfile(filepath=blend_filepath)
+        assert False, e
+    if blend_filepath:
+        bpy.ops.wm.save_as_mainfile(filepath=blend_filepath)
+    return result