fix: more explicit pre-conditions in tests

Author: fricklerhandwerk

src/shared/tests/test_fetch_all_channels.py

@@ -1,7 +1,9 @@
 from collections.abc import Callable, Generator
+from contextlib import contextmanager
 from unittest.mock import MagicMock, patch
 
 import pytest
+from django.conf import settings
 from django.core.management import call_command
 
 from shared.hydra import Jobset, JobsetInput, jobset_from_job
@@ -38,35 +40,47 @@ def test_input_branch_default(make_jobset: Callable[[str], Jobset]) -> None:
     assert jobset.input_branch("nixpkgs", default="master") == "master"
 
 
-_FAKE_SHA1 = "a" * 40
+@pytest.fixture
+def mock_hydra() -> Callable:
+    @contextmanager
+    def factory(channels: dict, jobsets: dict) -> Generator[None]:
+        client = MagicMock()
+        client.get_jobset.side_effect = jobsets.get
+        with (
+            patch(
+                "shared.management.commands.fetch_all_channels.channels",
+                channels,
+            ),
+            patch(
+                "shared.management.commands.fetch_all_channels.default_client",
+                return_value=client,
+            ),
+        ):
+            yield
+
+    return factory
 
 
 @pytest.fixture
-def hydra_mock() -> Generator[MagicMock]:
-    client = MagicMock()
-    client.get_jobset.side_effect = {
-        "nixpkgs/unstable": Jobset(
-            inputs={
-                "nixpkgs": JobsetInput(value="https://github.com/NixOS/nixpkgs.git")
-            }
-        ),
-        "nixos/unstable-small": Jobset(
-            inputs={
-                "nixpkgs": JobsetInput(value="https://github.com/NixOS/nixpkgs.git")
-            }
-        ),
-        "nixos/release-25.05-small": Jobset(
-            inputs={
-                "nixpkgs": JobsetInput(
-                    value="https://github.com/NixOS/nixpkgs.git release-25.05"
-                )
-            }
-        ),
-    }.get
+def mock_head_sha1() -> Callable:
+    @contextmanager
+    def factory(branch_shas: dict[str, str]) -> Generator[None]:
+        with patch(
+            "shared.management.commands.fetch_all_channels.get_head_sha1",
+            side_effect=lambda url, branch: branch_shas[branch],
+        ):
+            yield
+
+    return factory
+
+
+@pytest.mark.django_db
+def test_fetch_all_channels_creates_nix_branches(
+    mock_hydra: Callable, mock_head_sha1: Callable
+) -> None:
     with (
-        patch(
-            "shared.management.commands.fetch_all_channels.channels",
-            {
+        mock_hydra(
+            channels={
                 "nixpkgs-unstable": Channel(
                     job="nixpkgs/unstable/unstable",
                     status=ChannelState.UNSTABLE,
@@ -83,35 +97,31 @@ def hydra_mock() -> Generator[MagicMock]:
                     variant=Channel.Variant.SMALL,
                 ),
             },
+            jobsets={
+                "nixpkgs/unstable": Jobset(
+                    inputs={"nixpkgs": JobsetInput(value=f"{settings.GIT_CLONE_URL}")},
+                ),
+                "nixos/unstable-small": Jobset(
+                    inputs={"nixpkgs": JobsetInput(value=f"{settings.GIT_CLONE_URL}")},
+                ),
+                "nixos/release-25.05-small": Jobset(
+                    inputs={
+                        "nixpkgs": JobsetInput(
+                            value=f"{settings.GIT_CLONE_URL} release-25.05"
+                        )
+                    }
+                ),
+            },
         ),
-        patch(
-            "shared.management.commands.fetch_all_channels.default_client",
-            return_value=client,
-        ),
+        mock_head_sha1(branch_shas={"master": "a" * 40, "release-25.05": "b" * 40}),
     ):
-        yield client
-
-
-@pytest.fixture
-def head_sha1_mock() -> Generator[MagicMock]:
-    with patch(
-        "shared.management.commands.fetch_all_channels.get_head_sha1",
-        return_value=_FAKE_SHA1,
-    ) as mock_head:
-        yield mock_head
-
-
-@pytest.mark.django_db
-def test_fetch_all_channels_creates_nix_branches(
-    hydra_mock: MagicMock, head_sha1_mock: MagicMock
-) -> None:
-    call_command("fetch_all_channels")
+        call_command("fetch_all_channels")
 
     assert NixpkgsBranch.objects.filter(
-        name="master", head_sha1_commit=_FAKE_SHA1
+        name=settings.TRACKING_BRANCH, head_sha1_commit="a" * 40
     ).exists()
     assert NixpkgsBranch.objects.filter(
-        name="release-25.05", head_sha1_commit=_FAKE_SHA1
+        name="release-25.05", head_sha1_commit="b" * 40
     ).exists()
     assert NixChannel.objects.filter(channel_branch="nixpkgs-unstable").exists()
     assert NixChannel.objects.filter(channel_branch="nixos-unstable-small").exists()
@@ -120,20 +130,53 @@ def test_fetch_all_channels_creates_nix_branches(
 
 @pytest.mark.django_db
 def test_fetch_all_channels_small_variant_updates_branch(
-    hydra_mock: MagicMock,
-    head_sha1_mock: MagicMock,
+    mock_hydra: Callable, mock_head_sha1: Callable
 ) -> None:
     """
     Only small-variant channels fetch the Git HEAD.
     All other channels reuse the already-fetched branch.
     """
-    NixpkgsBranch.objects.create(name="master", head_sha1_commit="b" * 40)
-    NixpkgsBranch.objects.create(name="release-25.05", head_sha1_commit="c" * 40)
+    NixpkgsBranch.objects.create(name="master", head_sha1_commit="c" * 40)
+    NixpkgsBranch.objects.create(name="release-25.05", head_sha1_commit="d" * 40)
 
-    call_command("fetch_all_channels")
+    with (
+        mock_hydra(
+            channels={
+                "nixpkgs-unstable": Channel(
+                    job="nixpkgs/unstable/unstable",
+                    status=ChannelState.UNSTABLE,
+                    variant=Channel.Variant.PRIMARY,
+                ),
+                "nixos-unstable-small": Channel(
+                    job="nixos/unstable-small/tested",
+                    status=ChannelState.UNSTABLE,
+                    variant=Channel.Variant.SMALL,
+                ),
+                "nixos-25.05-small": Channel(
+                    job="nixos/release-25.05-small/tested",
+                    status=ChannelState.STABLE,
+                    variant=Channel.Variant.SMALL,
+                ),
+            },
+            jobsets={
+                "nixpkgs/unstable": Jobset(
+                    inputs={"nixpkgs": JobsetInput(value=f"{settings.GIT_CLONE_URL}")},
+                ),
+                "nixos/unstable-small": Jobset(
+                    inputs={"nixpkgs": JobsetInput(value=f"{settings.GIT_CLONE_URL}")},
+                ),
+                "nixos/release-25.05-small": Jobset(
+                    inputs={
+                        "nixpkgs": JobsetInput(
+                            value=f"{settings.GIT_CLONE_URL} release-25.05"
+                        )
+                    },
+                ),
+            },
+        ),
+        mock_head_sha1(branch_shas={"master": "a" * 40, "release-25.05": "b" * 40}),
+    ):
+        call_command("fetch_all_channels")
 
-    assert head_sha1_mock.call_count == 2
-    assert NixpkgsBranch.objects.get(name="master").head_sha1_commit == _FAKE_SHA1
-    assert (
-        NixpkgsBranch.objects.get(name="release-25.05").head_sha1_commit == _FAKE_SHA1
-    )
+    assert NixpkgsBranch.objects.get(name="master").head_sha1_commit == "a" * 40
+    assert NixpkgsBranch.objects.get(name="release-25.05").head_sha1_commit == "b" * 40