chore: exact and at least units are exclusive

juju/model.py

@@ -3149,7 +3149,7 @@ async def _check_idle(
 
                 ready_units.append(unit)
 
-            if len(ready_units) < _wait_for_units:
+            if wait_for_exact_units is None and len(ready_units) < _wait_for_units:
                 logging.info("Waiting for app %r units %s/%s",
                              app_name, len(ready_units), _wait_for_units)
                 return False

tests/unit/test_wait_for_idle.py

@@ -82,6 +82,19 @@ async def test_wrong_exact_count(full_status_response: dict, kwargs: dict, wrong
     assert not idle and not legacy
 
 
+async def test_exact_count_precedence(full_status_response: dict, kwargs: dict):
+    app = full_status_response["response"]["applications"]["hexanator"]
+    app["units"]["hexanator/1"] = copy.deepcopy(app["units"]["hexanator/0"])
+
+    kwargs["apps"] = ["hexanator"]
+    kwargs["wait_for_exact_units"] = 2
+    kwargs["wait_for_at_least_units"] = 9
+    kwargs["_wait_for_units"] = 9
+
+    idle, legacy = await model_fake(full_status_response).check_both(**kwargs)
+    assert idle and legacy
+
+
 async def test_ready_unit_count(full_status_response: dict, kwargs: dict):
     app = full_status_response["response"]["applications"]["hexanator"]
     app["units"]["hexanator/1"] = copy.deepcopy(app["units"]["hexanator/0"])