Enable parametrization by default (#5018)

* Enable parametrization by default

* Remove a way to disable parametrization

* Add a comment for the feature flag

tests/func/params/test_diff.py

@@ -151,7 +151,6 @@ def test_no_commits(tmp_dir):
 
 
 def test_vars_shows_on_params_diff(tmp_dir, scm, dvc):
-    dvc.config["feature"]["parametrization"] = True
     params_file = tmp_dir / "test_params.yaml"
     param_data = {"vars": {"model1": {"epoch": 15}, "model2": {"epoch": 35}}}
     dump_yaml(params_file, param_data)

tests/func/test_dvcfile.py

@@ -375,7 +375,6 @@ def test_dvcfile_dump_preserves_comments(tmp_dir, dvc):
 )
 def test_dvcfile_try_dumping_parametrized_stage(tmp_dir, dvc, data, name):
     dump_yaml("dvc.yaml", {"stages": data, "vars": [{"foo": "foobar"}]})
-    dvc.config["feature"]["parametrization"] = True
 
     stage = dvc.stage.load_one(name=name)
     dvcfile = stage.dvcfile

tests/func/test_feature_flags.py

@@ -1,29 +0,0 @@
-from dvc.dvcfile import Dvcfile
-from dvc.stage.loader import StageLoader
-from dvc.utils.serialize import dumps_yaml
-from tests.unit.test_stage_resolver import (
-    RESOLVED_DVC_YAML_DATA,
-    TEMPLATED_DVC_YAML_DATA,
-)
-
-
-def test_parametrization_is_not_enabled_by_default(tmp_dir, dvc, mocker):
-    assert dvc.config["feature"]["parametrization"] is False
-
-    (tmp_dir / "dvc.yaml").write_text(dumps_yaml(RESOLVED_DVC_YAML_DATA))
-    mock = mocker.patch("dvc.stage.loader.DataResolver")
-
-    stages = list(Dvcfile(dvc, "dvc.yaml").stages)
-    mock.assert_not_called()
-    assert len(stages) == 2
-
-
-def test_parametrization_flag_when_enabled(tmp_dir, dvc, mocker):
-    dvc.config["feature"]["parametrization"] = True
-
-    dvcfile = Dvcfile(dvc, "dvc.yaml")
-    loader = StageLoader(dvcfile, TEMPLATED_DVC_YAML_DATA, lockfile_data=None)
-    loader.resolved_data = RESOLVED_DVC_YAML_DATA["stages"]
-
-    stages = list(loader.values())
-    assert len(stages) == 2

tests/func/test_stage_load.py

@@ -147,7 +147,6 @@ def test_collect_not_a_group_stage_with_group_flag(tmp_dir, dvc, stages):
 
 
 def test_collect_generated(tmp_dir, dvc):
-    dvc.config["feature"]["parametrization"] = True
     d = {
         "vars": [{"vars": [1, 2, 3, 4, 5]}],
         "stages": {