fix typo

pytorch_lightning/trainer/connectors/accelerator_connector.py

@@ -461,6 +461,7 @@ def _set_parallel_devices_and_init_accelerator(self):
                 )
 
         self._gpus = self._device_flag if not self._gpus else self._gpus
+        self._tpu_cores = self._device_flag if not self._tpu_cores else self._tpu_cores
 
     def _choose_and_init_cluster_environment(self):
         self.cluster_environment = LightningEnvironment()
@@ -484,7 +485,7 @@ def _is_slurm_managing_tasks(self):
         return num_slurm_tasks == total_requested_devices
 
     def _choose_strategy(self):
-        if self._accelerator_flag == "ipu_strategy":
+        if self._accelerator_flag == "ipu":
             self._strategy_flag = "ipu_strategy"
         elif self._accelerator_flag == "tpu":
             if self._parallel_devices and len(self._parallel_devices) > 1:
@@ -757,15 +758,15 @@ def devices(self):
         return 0
 
     @property
-    def tpu_cores(self) -> int:
+    def tpu_cores(self):
         if isinstance(self.accelerator, TPUAccelerator):
-            return self.devices
+            return self._tpu_cores
         return 0
 
     @property
     def tpu_id(self) -> Optional[int]:
         if isinstance(self.accelerator, TPUAccelerator):
-            return self.parallel_devices[0]
+            return self.tpu_cores[0]
         return None
 
     @property

tests/accelerators/test_ipu.py

@@ -115,7 +115,7 @@ def test_accelerator_selected(tmpdir):
 @RunIf(ipu=True)
 def test_warning_if_ipus_not_used(tmpdir):
     with pytest.warns(UserWarning, match="IPU available but not used. Set the `ipus` flag in your trainer"):
-        Trainer(default_root_dir=tmpdir)
+        Trainer(default_root_dir=tmpdir, accelerator="cpu")
 
 
 @RunIf(ipu=True)