[ci] Push branch-tagged docker images to ghcr.io for local testing (#16992)

tests/script/test_docker_build.py

@@ -0,0 +1,169 @@
+"""Unit tests for docker/build.py command generation."""
+
+import importlib.util
+from pathlib import Path
+import sys
+
+import pytest
+
+_BUILD_PY = Path(__file__).parents[2] / "docker" / "build.py"
+_spec = importlib.util.spec_from_file_location("docker_build", _BUILD_PY)
+docker_build = importlib.util.module_from_spec(_spec)
+_spec.loader.exec_module(docker_build)
+
+
+def _run(capsys: pytest.CaptureFixture[str], *argv: str) -> list[str]:
+    """Run build.py main() in dry-run mode and return the emitted commands."""
+    full_argv = ["build.py", "--dry-run", *argv]
+    with pytest.MonkeyPatch.context() as mp:
+        mp.setattr(sys, "argv", full_argv)
+        docker_build.main()
+    out = capsys.readouterr().out
+    return [line[2:] for line in out.splitlines() if line.startswith("$ ")]
+
+
+def test_branch_build_pushes_single_ghcr_tag_without_cache_to(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "my-branch",
+        "--arch",
+        "amd64",
+        "--build-type",
+        "docker",
+        "--registry",
+        "ghcr",
+        "build",
+        "--push",
+        "--no-cache-to",
+    )
+
+    assert len(commands) == 1
+    cmd = commands[0]
+    # Custom tag -> only the tag itself, no companion "dev"/"latest" tags
+    assert "--tag ghcr.io/esphome/esphome-amd64:my-branch" in cmd
+    assert ":dev" not in cmd
+    # ghcr only -> no Docker Hub image name
+    assert "--tag esphome/esphome-amd64:my-branch" not in cmd
+    # custom tag falls back to the dev cache for reads
+    assert (
+        "--cache-from type=registry,ref=ghcr.io/esphome/esphome-amd64:cache-dev" in cmd
+    )
+    assert "--push" in cmd
+    # --no-cache-to must suppress the cache write
+    assert "--cache-to" not in cmd
+
+
+def test_branch_manifest_targets_ghcr_only(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "my-branch",
+        "--build-type",
+        "ha-addon",
+        "--registry",
+        "ghcr",
+        "manifest",
+    )
+
+    assert commands == [
+        "docker buildx imagetools create "
+        "--tag ghcr.io/esphome/esphome-hassio:my-branch "
+        "ghcr.io/esphome/esphome-hassio-amd64:my-branch "
+        "ghcr.io/esphome/esphome-hassio-aarch64:my-branch"
+    ]
+
+
+def test_release_build_keeps_both_registries_and_cache_to(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "2025.6.0",
+        "--arch",
+        "amd64",
+        "--build-type",
+        "docker",
+        "build",
+        "--push",
+    )
+
+    cmd = commands[0]
+    # Default (no --registry) keeps both Docker Hub and ghcr image names
+    assert "--tag esphome/esphome-amd64:2025.6.0" in cmd
+    assert "--tag ghcr.io/esphome/esphome-amd64:2025.6.0" in cmd
+    # Release channel still gets its companion tags
+    assert "--tag esphome/esphome-amd64:latest" in cmd
+    # Without --no-cache-to the cache write is preserved
+    assert (
+        "--cache-to type=registry,ref=ghcr.io/esphome/esphome-amd64:cache-latest,mode=max"
+        in cmd
+    )
+
+
+def test_build_no_push_omits_push_and_cache(
+    capsys: pytest.CaptureFixture[str],
+) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "my-branch",
+        "--arch",
+        "amd64",
+        "--build-type",
+        "docker",
+        "--registry",
+        "ghcr",
+        "build",
+    )
+
+    cmd = commands[0]
+    assert "--tag ghcr.io/esphome/esphome-amd64:my-branch" in cmd
+    assert "--push" not in cmd
+    assert "--cache-to" not in cmd
+
+
+def test_build_dockerhub_only(capsys: pytest.CaptureFixture[str]) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "my-branch",
+        "--arch",
+        "amd64",
+        "--build-type",
+        "docker",
+        "--registry",
+        "dockerhub",
+        "build",
+        "--push",
+    )
+
+    cmd = commands[0]
+    assert "--tag esphome/esphome-amd64:my-branch" in cmd
+    assert "ghcr.io" not in cmd
+    # Cache reference falls back to Docker Hub when GHCR isn't selected
+    assert "--cache-from type=registry,ref=esphome/esphome-amd64:cache-dev" in cmd
+
+
+def test_manifest_dockerhub_only(capsys: pytest.CaptureFixture[str]) -> None:
+    commands = _run(
+        capsys,
+        "--tag",
+        "my-branch",
+        "--build-type",
+        "docker",
+        "--registry",
+        "dockerhub",
+        "manifest",
+    )
+
+    create = commands[0]
+    assert create.startswith(
+        "docker buildx imagetools create --tag esphome/esphome:my-branch "
+    )
+    assert "ghcr.io" not in create