locker: ensure dependency constraint is correct

Resolves: python-poetry#3115

poetry/packages/locker.py

@@ -417,23 +417,43 @@ def _lock_packages(
 
         return locked
 
+    def _dump_dependency(self, dependency):  # type: (Dependency) -> Union[str, dict]
+        constraint = inline_table()
+
+        if dependency.is_vcs():
+            constraint["git"] = dependency.source_url
+            if dependency.source_resolved_reference:
+                constraint["rev"] = dependency.source_resolved_reference
+            else:
+                for key in {"branch", "tag", "rev"}:
+                    value = getattr(dependency, key, None)
+                    if value is not None:
+                        constraint[key] = value
+        elif dependency.is_url():
+            constraint["url"] = dependency.source_url
+        elif dependency.is_file() or dependency.is_directory():
+            constraint["path"] = dependency.source_url
+        else:
+            constraint["version"] = str(dependency.pretty_constraint)
+
+        if dependency.extras:
+            constraint["extras"] = sorted(dependency.extras)
+
+        if dependency.is_optional():
+            constraint["optional"] = True
+
+        if not dependency.marker.is_any():
+            constraint["markers"] = str(dependency.marker)
+
+        return constraint
+
     def _dump_package(self, package):  # type: (Package) -> dict
         dependencies = {}
         for dependency in sorted(package.requires, key=lambda d: d.name):
             if dependency.pretty_name not in dependencies:
                 dependencies[dependency.pretty_name] = []
 
-            constraint = inline_table()
-            constraint["version"] = str(dependency.pretty_constraint)
-
-            if dependency.extras:
-                constraint["extras"] = sorted(dependency.extras)
-
-            if dependency.is_optional():
-                constraint["optional"] = True
-
-            if not dependency.marker.is_any():
-                constraint["markers"] = str(dependency.marker)
+            constraint = self._dump_dependency(dependency)
 
             dependencies[dependency.pretty_name].append(constraint)