VersionRange.constraints are not an iterable of an iterable

[Hritik14]

Commit 80b515a changes how constraints are populated.
This messes up with the assumption that constraints are an iterable of iterables (here, list, in future - tuple).
https://github.com/nexB/univers/blob/ca2cf4da77303bc8ead9ee2c6475b7a68ac81e26/src/univers/version_range.py#L41-L43

Commit: 80b515a

-        # parse_constraints
-        version_constraints = []
-        for or_constraints in constraints.split("|"):
-            and_constraints = []
-            for constraint in or_constraints.split(","):
-                constraint = VersionConstraint.from_string(
-                    string=constraint,
-                    version_class=range_class.version_class,
-                )
-                and_constraints.append(constraint)
-            version_constraints.append(and_constraints)
+        # There is only one star: "*" must only occur once and alone in a range,
+        # without any other constraint or version.
+        if constraints.startswith("*"):
+            if constraints != "*":
+                raise ValueError(f"{vers!r} contains an invalid '*' constraint.")
+            return range_class([VersionConstraint.from_string(string="*", version_class=None)])
+
+        parsed_constraints = []
+
+        constraints = constraints.strip("|")
+        for const in constraints.split("|"):
+            constraint = VersionConstraint.from_string(
+                string=const,
+                version_class=version_class,
+            )
+            parsed_constraints.append(constraint)

[Hritik14]

Philippe Ombredanne
@pombredanne
16:57
@Hritik14 re: #22

This messes up with the assumption that constraints are an iterable of iterables (here, list, in future - tuple).

this has changed and now a range is always a flat list of constraints
not nested seqs/iterable anymore
that's the major simplification changes in the latest vers spec draft