Transitive transformers

src/rachis/core/archive/tests/test_citations.py

@@ -39,7 +39,7 @@ def test_import(self):
         obs = list(map(lambda item: (item[0], item[1].fields['title']),
                        archiver.citations.items()))
 
-        self.assertEqual(obs, expected)
+        self.assertEqual(sorted(obs), sorted(expected))
 
         with (archiver.provenance_dir / 'action' / 'action.yaml').open() as fh:
             action_yaml = fh.read()
@@ -77,7 +77,7 @@ def test_action(self):
         obs = list(map(lambda item: (item[0], item[1].fields['title']),
                        archiver.citations.items()))
 
-        self.assertEqual(obs, expected)
+        self.assertEqual(sorted(obs), sorted(expected))
 
         with (archiver.provenance_dir / 'action' / 'action.yaml').open() as fh:
             action_yaml = fh.read()

src/rachis/core/testing/format.py

@@ -171,3 +171,28 @@ class ExportableOnlyFormat(TextFileFormat):
     """
     A format that can only be transformed to.
     """
+
+class FirstStepFormat(model.DirectoryFormat):
+    """
+    A format for testing transitive transformers
+    """
+
+class SecondStepFormat(model.DirectoryFormat):
+    """
+    A format for testing transitive transformers
+    """
+
+class ThirdStepFormat(model.DirectoryFormat):
+    """
+    A format for testing transitive transformers
+    """
+
+class FourthStepFormat(model.DirectoryFormat):
+    """
+    A format for testing transitive transformers
+    """
+
+class FifthStepFormat(model.DirectoryFormat):
+    """
+    A format for testing transitive transformers
+    """

src/rachis/core/testing/plugin.py

@@ -30,12 +30,18 @@
     Cephalapod,
     CephalapodDirectoryFormat,
     ImportableOnlyFormat,
-    ExportableOnlyFormat
+    ExportableOnlyFormat,
+    FirstStepFormat,
+    SecondStepFormat,
+    ThirdStepFormat,
+    FourthStepFormat,
+    FifthStepFormat,
 )
 
 from .type import (IntSequence1, IntSequence2, IntSequence3, Mapping, FourInts,
                    SingleInt, Kennel, Dog, Cat, C1, C2, C3, Foo, Bar, Baz,
-                   AscIntSequence, Squid, Octopus, Cuttlefish)
+                   AscIntSequence, Squid, Octopus, Cuttlefish, FirstStep,
+                   SecondStep, ThirdStep, FourthStep, FifthStep)
 from .method import (concatenate_ints, split_ints, merge_mappings,
                      identity_with_metadata, identity_with_metadata_column,
                      identity_with_categorical_metadata_column,
@@ -120,7 +126,9 @@
     IntSequenceFormatV2, MappingFormat, IntSequenceV2DirectoryFormat,
     IntSequenceMultiFileDirectoryFormat, MappingDirectoryFormat,
     EchoDirectoryFormat, EchoFormat, Cephalapod, CephalapodDirectoryFormat,
-    ImportableOnlyFormat, ExportableOnlyFormat)
+    ImportableOnlyFormat, ExportableOnlyFormat, FirstStepFormat,
+    SecondStepFormat, ThirdStepFormat, FourthStepFormat, FifthStepFormat,
+)
 
 dummy_plugin.register_formats(
     FourIntsDirectoryFormat, UnimportableDirectoryFormat, UnimportableFormat,
@@ -182,6 +190,37 @@ def factory():
     description="The second IntSequence",
     examples={'IntSequence2 import example': is2_use}
 )
+
+dummy_plugin.register_artifact_class(
+    FirstStep,
+    directory_format=FirstStepFormat,
+    description="First step"
+)
+
+dummy_plugin.register_artifact_class(
+    SecondStep,
+    directory_format=SecondStepFormat,
+    description="Second step"
+)
+
+dummy_plugin.register_artifact_class(
+    ThirdStep,
+    directory_format=ThirdStepFormat,
+    description="Third step"
+)
+
+dummy_plugin.register_artifact_class(
+    FourthStep,
+    directory_format=FourthStepFormat,
+    description="Fourth step"
+)
+
+dummy_plugin.register_artifact_class(
+    FifthStep,
+    directory_format=FifthStepFormat,
+    description="Fifth step"
+)
+
 dummy_plugin.register_semantic_type_to_format(
     IntSequence3,
     directory_format=IntSequenceMultiFileDirectoryFormat

src/rachis/core/testing/transformer.py

@@ -23,7 +23,12 @@
     RedundantSingleIntDirectoryFormat,
     EchoFormat,
     ImportableOnlyFormat,
-    ExportableOnlyFormat
+    ExportableOnlyFormat,
+    FirstStepFormat,
+    SecondStepFormat,
+    ThirdStepFormat,
+    FourthStepFormat,
+    FifthStepFormat,
 )
 from .plugin import dummy_plugin, citations
 
@@ -206,3 +211,27 @@ def _4242(data: ImportableOnlyFormat) -> IntSequenceDirectoryFormat:
 @dummy_plugin.register_transformer()
 def _4243(data: IntSequenceDirectoryFormat) -> ExportableOnlyFormat:
     return ExportableOnlyFormat()
+
+
+# only for testing transitive transformers
+@dummy_plugin.register_transformer(upgrade=True)
+def _6000(data: FirstStepFormat) -> SecondStepFormat:
+    return SecondStepFormat()
+
+
+# only for testing transitive transformers
+@dummy_plugin.register_transformer(upgrade=True)
+def _6001(data: SecondStepFormat) -> ThirdStepFormat:
+    return ThirdStepFormat()
+
+
+# only for testing transitive transformers
+@dummy_plugin.register_transformer
+def _6002(data: ThirdStepFormat) -> FourthStepFormat:
+    return FourthStepFormat()
+
+
+# only for testing transitive transformers
+@dummy_plugin.register_transformer(upgrade=False)
+def _6003(data: ThirdStepFormat) -> FifthStepFormat:
+    return FifthStepFormat()

src/rachis/core/testing/type.py

@@ -45,3 +45,9 @@
 Squid = plugin.SemanticType('Squid')
 Octopus = plugin.SemanticType('Octopus')
 Cuttlefish = plugin.SemanticType('Cuttlefish')
+
+FirstStep = plugin.SemanticType('FirstStep')
+SecondStep = plugin.SemanticType('SecondStep')
+ThirdStep = plugin.SemanticType('ThirdStep')
+FourthStep = plugin.SemanticType('FourthStep')
+FifthStep = plugin.SemanticType('FifthStep')

src/rachis/core/tests/test_transform.py

@@ -0,0 +1,60 @@
+import unittest
+from typing import Union
+from tempfile import TemporaryDirectory
+
+from rachis import Artifact
+from rachis.core.testing.format import (
+    ThirdStepFormat, FourthStepFormat, FifthStepFormat, Cephalapod)
+
+
+class TestTransitiveTransfomrers(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        with TemporaryDirectory() as tempdir:
+            cls.first_format = Artifact.import_data(
+                type='FirstStep', view=tempdir
+            )
+
+        cls.int_sequence = Artifact.import_data(
+            type='IntSequence1', view=[1, 2, 3]
+        )
+
+    def test_first_to_third(self):
+        """
+        Path exists and is upgraded.
+        FirstStepFormat -> SecondStepFormat -> ThirdStepFormat
+        """
+        view = self.first_format.view(ThirdStepFormat)
+        self.assertEqual(type(view), ThirdStepFormat)
+
+    def test_first_to_fourth_fails(self):
+        """
+        Path exists but is not upgraded.
+        FirstStepFormat -> SecondStepFormat -> ThirdStepFormat -None-> Fourth
+        """
+        with self.assertRaisesRegex(Exception, 'No transformation from'):
+            self.first_format.view(FourthStepFormat)
+
+    def test_union_transitivity(self):
+        """
+        Path exists between FirstStepFormat and ThirdStepFormat but not between
+        FirsStepFormat and Cephalapod.
+        """
+        view = self.first_format.view(Union[Cephalapod, ThirdStepFormat])
+        self.assertEqual(type(view), ThirdStepFormat)
+
+    def test_int_sequence_dir_to_list(self):
+        """
+        Tests that unwrapping a format and then transforming does not require
+        upgrading the path.
+        """
+        view = self.int_sequence.view(list)
+        self.assertEqual(type(view), list)
+
+    def test_lossy_transformer(self):
+        """
+        Tests that path with lossy steps still completes.
+        First -> Second -> Third -lossy-> Fifth
+        """
+        view = self.first_format.view(FifthStepFormat)
+        self.assertEqual(type(view), FifthStepFormat)