Fix blockers list in rwlock error message (#3285)

dvc/rwlock.py

@@ -66,10 +66,11 @@ def _infos_to_str(infos):
 def _check_blockers(lock, info, *, mode, waiters):
     for path_info in waiters:
         blockers = [
-            info
+            blocker
             for path, infos in lock[mode].items()
             if path_info.overlaps(path)
-            if info not in (infos if type(infos) is list else [infos])
+            for blocker in (infos if isinstance(infos, list) else [infos])
+            if blocker != info
         ]
 
         if not blockers:

tests/unit/test_rwlock.py

@@ -62,12 +62,12 @@ def test_rwlock_subdirs(tmp_path):
     subfoo = PathInfo("foo/subfoo")
 
     with rwlock(path, "cmd1", [foo], []):
-        with pytest.raises(LockError):
+        with pytest.raises(LockError, match=r"subfoo(.|\n)*cmd1"):
             with rwlock(path, "cmd2", [], [subfoo]):
                 pass
 
     with rwlock(path, "cmd1", [], [subfoo]):
-        with pytest.raises(LockError):
+        with pytest.raises(LockError, match=r"'foo'(.|\n)*cmd1"):
             with rwlock(path, "cmd2", [foo], []):
                 pass