Display error when forming new ZHA network fails (home-assistant#157863)

Author: TheJulianJES

homeassistant/components/zha/config_flow.py

@@ -680,6 +680,13 @@ async def async_step_form_new_network(
 
         try:
             await self._form_network_task
+        except Exception as exc:
+            _LOGGER.exception("Failed to form new network")
+            self._progress_error = AbortFlow(
+                reason="cannot_form_network",
+                description_placeholders={"error": str(exc)},
+            )
+            return self.async_show_progress_done(next_step_id="progress_failed")
         finally:
             self._form_network_task = None
 

homeassistant/components/zha/strings.json

@@ -1,6 +1,7 @@
 {
   "config": {
     "abort": {
+      "cannot_form_network": "Could not form a new Zigbee network.\n\nError: {error}",
       "cannot_resolve_path": "Could not resolve device path: {path}",
       "cannot_restore_backup": "The adapter you are restoring to does not properly support backup restoration. Please upgrade the firmware.\n\nError: {error}",
       "cannot_restore_backup_no_ieee_confirm": "The adapter you are restoring to has outdated firmware and cannot write the adapter IEEE address multiple times. Please upgrade the firmware or confirm permanent overwrite in the previous step.",
@@ -1923,6 +1924,7 @@
   },
   "options": {
     "abort": {
+      "cannot_form_network": "[%key:component::zha::config::abort::cannot_form_network%]",
       "cannot_resolve_path": "[%key:component::zha::config::abort::cannot_resolve_path%]",
       "cannot_restore_backup": "[%key:component::zha::config::abort::cannot_restore_backup%]",
       "cannot_restore_backup_no_ieee_confirm": "[%key:component::zha::config::abort::cannot_restore_backup_no_ieee_confirm%]",

tests/components/zha/test_config_flow.py

@@ -1813,6 +1813,36 @@ async def form_network_side_effect(*args, **kwargs):
     assert result2["type"] is FlowResultType.CREATE_ENTRY
 
 
+async def test_formation_strategy_form_initial_network_failure(
+    advanced_pick_radio: RadioPicker, mock_app: AsyncMock, hass: HomeAssistant
+) -> None:
+    """Test forming a new network that fails with an exception."""
+    # Mock form_network to raise an exception
+    mock_app.form_network.side_effect = DelayedAsyncMock(
+        side_effect=Exception("Network formation failed")
+    )
+
+    result = await advanced_pick_radio(RadioType.ezsp)
+    result_form = await hass.config_entries.flow.async_configure(
+        result["flow_id"],
+        user_input={"next_step_id": config_flow.FORMATION_FORM_NEW_NETWORK},
+    )
+
+    result2 = await consume_progress_flow(
+        hass,
+        flow_id=result_form["flow_id"],
+        valid_step_ids=("form_new_network",),
+    )
+    await hass.async_block_till_done()
+
+    assert result2["type"] is FlowResultType.ABORT
+    assert result2["reason"] == "cannot_form_network"
+    assert "Network formation failed" in result2["description_placeholders"]["error"]
+
+    # Verify form_network was called
+    mock_app.form_network.assert_called_once()
+
+
 @patch(f"zigpy_znp.{PROBE_FUNCTION_PATH}", AsyncMock(return_value=True))
 @patch("homeassistant.components.zha.async_setup_entry", AsyncMock(return_value=True))
 async def test_onboarding_auto_formation_new_hardware(