chore: consolidate CI and expand Windows test coverage (#2498)

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

pkg/collector/collection_test.go

@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// Copyright The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build windows
+
+package collector_test
+
+import (
+	"errors"
+	"log/slog"
+	"testing"
+	"time"
+
+	"github.com/alecthomas/kingpin/v2"
+	"github.com/prometheus-community/windows_exporter/internal/mi"
+	"github.com/prometheus-community/windows_exporter/internal/pdh"
+	"github.com/prometheus-community/windows_exporter/pkg/collector"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCollectionConstructors(t *testing.T) {
+	t.Parallel()
+
+	t.Run("config includes every collector", func(t *testing.T) {
+		t.Parallel()
+
+		collection := collector.NewWithConfig(collector.Config{})
+		_, err := collection.NewHandler(time.Second, slog.New(slog.DiscardHandler), collector.Available())
+		require.NoError(t, err)
+	})
+
+	t.Run("flags include every collector", func(t *testing.T) {
+		t.Parallel()
+
+		app := kingpin.New("test", "test")
+		collection := collector.NewWithFlags(app)
+		_, err := app.Parse(nil)
+		require.NoError(t, err)
+		_, err = collection.NewHandler(time.Second, slog.New(slog.DiscardHandler), collector.Available())
+		require.NoError(t, err)
+	})
+}
+
+func TestCollectionBuildAndClose(t *testing.T) {
+	t.Parallel()
+
+	buildFailure := errors.New("build failed")
+
+	closeFailure := errors.New("close failed")
+	for _, tc := range []struct {
+		name         string
+		buildErr     error
+		closeErr     error
+		wantBuildErr error
+	}{
+		{name: "success"},
+		{name: "build failure", buildErr: buildFailure, wantBuildErr: buildFailure},
+		{name: "optional counter missing", buildErr: pdh.ErrNoData},
+		{name: "close failure", closeErr: closeFailure},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			test := &lifecycleCollector{name: "test", buildErr: tc.buildErr, closeErr: tc.closeErr}
+			collection := collector.New(collector.Map{"test": test})
+			err := collection.Build(t.Context(), slog.New(slog.DiscardHandler))
+			t.Cleanup(func() {
+				err := collection.Close()
+				if tc.closeErr != nil {
+					require.ErrorIs(t, err, tc.closeErr)
+				} else {
+					require.NoError(t, err)
+				}
+
+				require.True(t, test.closed)
+			})
+
+			if tc.wantBuildErr != nil {
+				require.ErrorIs(t, err, tc.wantBuildErr)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}
+
+type lifecycleCollector struct {
+	name     string
+	buildErr error
+	closeErr error
+	closed   bool
+}
+
+func (c *lifecycleCollector) GetName() string { return c.name }
+
+func (c *lifecycleCollector) Build(_ *slog.Logger, _ *mi.Session) error { return c.buildErr }
+
+func (c *lifecycleCollector) Collect(_ chan<- prometheus.Metric, _ time.Duration) error { return nil }
+
+func (c *lifecycleCollector) Close() error {
+	c.closed = true
+
+	return c.closeErr
+}