Amend grid connection tests

All the grid connection tests now use the microgrid to instantiate
the grid connection.

The test that was checking for multiple grid connections was
removed, because the component graph does not accept multiple
grid connections.

Signed-off-by: Daniel Zullo <[email protected]>

Author: daniel-zullo-frequenz

tests/microgrid/test_grid.py

@@ -3,25 +3,40 @@
 
 """Tests for the `Grid` module."""
 
+from pytest_mock import MockerFixture
+
+import frequenz.sdk.microgrid.component_graph as gr
+from frequenz.sdk import microgrid
+from frequenz.sdk.microgrid.client import Connection
 from frequenz.sdk.microgrid.component import Component, ComponentCategory, GridMetadata
 from frequenz.sdk.timeseries import Current, Fuse
-from frequenz.sdk.timeseries import grid as _grid
+
+from ..timeseries.mock_microgrid import MockMicrogrid
 
 
-async def test_grid_1() -> None:
+async def test_grid_1(mocker: MockerFixture) -> None:
     """Test the grid connection module."""
     # The tests here need to be in this exact sequence, because the grid connection
     # is a singleton. Once it gets created, it stays in memory for the duration of
     # the tests, unless we explicitly delete it.
 
     # validate that islands with no grid connection are accepted.
-    components = [
+    components = {
+        Component(1, ComponentCategory.NONE),
         Component(2, ComponentCategory.METER),
-    ]
+    }
+    connections = {
+        Connection(1, 2),
+    }
+    # pylint: disable=protected-access
+    graph = gr._MicrogridComponentGraph(components=components, connections=connections)
+
+    mockgrid = MockMicrogrid(graph=graph)
+    await mockgrid.start(mocker)
+    grid = microgrid.grid()
 
-    _grid.initialize(components)
-    grid = _grid.get()
     assert grid is None
+    await mockgrid.cleanup()
 
 
 def _create_fuse() -> Fuse:
@@ -35,42 +50,26 @@ def _create_fuse() -> Fuse:
     return fuse
 
 
-async def test_grid_2() -> None:
-    """Test the grid connection module, slightly more complex.
-
-    Validate that the microgrid initialization fails
-    when there are multiple grid connection points.
-    """
-    fuse = _create_fuse()
-
-    components = [
-        Component(1, ComponentCategory.GRID, None, GridMetadata(fuse)),
-        Component(2, ComponentCategory.GRID, None, GridMetadata(fuse)),
-        Component(3, ComponentCategory.METER),
-    ]
-
-    try:
-        _grid.initialize(components)
-        assert False, "Expected microgrid.grid() to raise a RuntimeError."
-    except RuntimeError:
-        pass
-
-
-async def test_grid_3() -> None:
+async def test_grid_2(mocker: MockerFixture) -> None:
     """Validate that microgrids with one grid connection are accepted."""
-    components = [
+    components = {
         Component(1, ComponentCategory.GRID, None, GridMetadata(_create_fuse())),
         Component(2, ComponentCategory.METER),
-    ]
+    }
+    connections = {
+        Connection(1, 2),
+    }
 
-    _grid.initialize(components)
-    grid = _grid.get()
+    # pylint: disable=protected-access
+    graph = gr._MicrogridComponentGraph(components=components, connections=connections)
+
+    mockgrid = MockMicrogrid(graph=graph)
+    await mockgrid.start(mocker)
+
+    grid = microgrid.grid()
     assert grid is not None
 
     expected_fuse_current = Current.from_amperes(123.0)
     expected_fuse = Fuse(expected_fuse_current)
 
-    assert grid == _grid.Grid(fuse=expected_fuse)
-
-    fuse_current = grid.fuse.max_current
-    assert fuse_current == expected_fuse_current
+    assert grid.fuse == expected_fuse