serialization: dont rely on the default hash type (#4466)

Prerequisite for #4144 and #3069

dvc/output/base.py

@@ -172,18 +172,10 @@ class BaseOutput:
     def cache_path(self):
         return self.cache.tree.hash_to_path_info(self.checksum).url
 
-    @property
-    def checksum_type(self):
-        return self.tree.PARAM_CHECKSUM
-
     @property
     def checksum(self):
         return self.info.get(self.tree.PARAM_CHECKSUM)
 
-    @checksum.setter
-    def checksum(self, checksum):
-        self.info[self.tree.PARAM_CHECKSUM] = checksum
-
     def get_checksum(self):
         return self.tree.get_hash(self.path_info)[1]
 

dvc/stage/loader.py

@@ -42,7 +42,9 @@ class StageLoader(Mapping):
             if isinstance(item, dependency.ParamsDependency):
                 item.fill_values(get_in(lock_data, [stage.PARAM_PARAMS, path]))
                 continue
-            item.checksum = get_in(checksums, [key, path, item.checksum_type])
+            item.info = get_in(checksums, [key, path], {})
+            item.info = item.info.copy()
+            item.info.pop("path", None)
 
     @classmethod
     def load_stage(cls, dvcfile, name, stage_data, lock_data=None):

dvc/stage/serialize.py

@@ -138,12 +138,7 @@ def to_single_stage_lockfile(stage: "Stage") -> dict:
     params, deps = split_params_deps(stage)
     deps, outs = [
         [
-            OrderedDict(
-                [
-                    (PARAM_PATH, item.def_path),
-                    (item.checksum_type, item.checksum),
-                ]
-            )
+            OrderedDict([(PARAM_PATH, item.def_path), *item.info.items()])
             for item in sort_by_path(items)
         ]
         for items in [deps, stage.outs]

tests/func/test_run_cache.py

@@ -76,7 +76,7 @@ def test_uncached_outs_are_cached(tmp_dir, dvc, run_copy):
         name="copy-foo-bar",
     )
     with dvc.state:
-        stage.outs[0].checksum = stage.outs[0].get_checksum()
+        stage.outs[0].info = stage.outs[0].save_info()
     assert os.path.exists(relpath(stage.outs[0].cache_path))
 
 

tests/unit/stage/test_serialize_pipeline_lock.py

@@ -144,11 +144,31 @@ def test_lock_outs_order(dvc, typ):
     )
 
 
-def test_dump_appropriate_checksums(dvc):
+def test_dump_nondefault_hash(dvc):
     stage = create_stage(
         PipelineStage, dvc, deps=["s3://dvc-temp/file"], **kwargs
     )
-    stage.deps[0].info = {"etag": "is-it-etag", "md5": "or-md5?"}
+    stage.deps[0].info = {"md5": "value"}
+    assert to_single_stage_lockfile(stage) == OrderedDict(
+        [
+            ("cmd", "command"),
+            (
+                "deps",
+                [
+                    OrderedDict(
+                        [("path", "s3://dvc-temp/file"), ("md5", "value")]
+                    )
+                ],
+            ),
+        ]
+    )
+
+
+def test_dump_multiple_hashes(dvc):
+    stage = create_stage(
+        PipelineStage, dvc, deps=["s3://dvc-temp/file"], **kwargs
+    )
+    stage.deps[0].info = {"etag": "etag-value", "md5": "md5-value"}
     assert to_single_stage_lockfile(stage) == OrderedDict(
         [
             ("cmd", "command"),
@@ -158,7 +178,8 @@ def test_dump_appropriate_checksums(dvc):
                     OrderedDict(
                         [
                             ("path", "s3://dvc-temp/file"),
-                            ("etag", "is-it-etag"),
+                            ("etag", "etag-value"),
+                            ("md5", "md5-value"),
                         ]
                     )
                 ],