1 files changed, 106 insertions, 0 deletions
diff --git a/cache/filecache/filecache_integration_test.go b/cache/filecache/filecache_integration_test.go
new file mode 100644
index 000000000..1e920c29f
--- /dev/null
+++ b/cache/filecache/filecache_integration_test.go
@@ -0,0 +1,106 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// 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.
+
+package filecache_test
+
+import (
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/bep/logg"
+	qt "github.com/frankban/quicktest"
+	"github.com/gohugoio/hugo/htesting"
+	"github.com/gohugoio/hugo/hugolib"
+)
+
+// See issue #10781. That issue wouldn't have been triggered if we kept
+// the empty root directories (e.g. _resources/gen/images).
+// It's still an upstream Go issue that we also need to handle, but
+// this is a test for the first part.
+func TestPruneShouldPreserveEmptyCacheRoots(t *testing.T) {
+	files := `
+-- hugo.toml --
+baseURL = "https://example.com"
+-- content/_index.md --
+---
+title: "Home"
+---
+
+`
+
+	b := hugolib.NewIntegrationTestBuilder(
+		hugolib.IntegrationTestConfig{T: t, TxtarString: files, RunGC: true, NeedsOsFS: true},
+	).Build()
+
+	_, err := b.H.BaseFs.ResourcesCache.Stat(filepath.Join("_gen", "images"))
+
+	b.Assert(err, qt.IsNil)
+}
+
+func TestPruneImages(t *testing.T) {
+	if htesting.IsCI() {
+		// TODO(bep)
+		t.Skip("skip flaky test on CI server")
+	}
+	t.Skip("skip flaky test")
+	files := `
+-- hugo.toml --
+baseURL = "https://example.com"
+[caches]
+[caches.images]
+maxAge = "200ms"
+dir = ":resourceDir/_gen"
+-- content/_index.md --
+---
+title: "Home"
+---
+-- assets/a/pixel.png --
+iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNkYPhfDwAChwGA60e6kgAAAABJRU5ErkJggg==
+-- layouts/index.html --
+{{ warnf "HOME!" }}
+{{ $img := resources.GetMatch "**.png" }}
+{{ $img = $img.Resize "3x3" }}
+{{ $img.RelPermalink }}
+
+
+
+`
+
+	b := hugolib.NewIntegrationTestBuilder(
+		hugolib.IntegrationTestConfig{T: t, TxtarString: files, Running: true, RunGC: true, NeedsOsFS: true, LogLevel: logg.LevelInfo},
+	).Build()
+
+	b.Assert(b.GCCount, qt.Equals, 0)
+	b.Assert(b.H, qt.IsNotNil)
+
+	imagesCacheDir := filepath.Join("_gen", "images")
+	_, err := b.H.BaseFs.ResourcesCache.Stat(imagesCacheDir)
+
+	b.Assert(err, qt.IsNil)
+
+	// TODO(bep) we need a way to test full rebuilds.
+	// For now, just sleep a little so the cache elements expires.
+	time.Sleep(500 * time.Millisecond)
+
+	b.RenameFile("assets/a/pixel.png", "assets/b/pixel2.png").Build()
+
+	b.Assert(b.GCCount, qt.Equals, 1)
+	// Build it again to GC the empty a dir.
+	b.Build()
+
+	_, err = b.H.BaseFs.ResourcesCache.Stat(filepath.Join(imagesCacheDir, "a"))
+	b.Assert(err, qt.Not(qt.IsNil))
+	_, err = b.H.BaseFs.ResourcesCache.Stat(imagesCacheDir)
+	b.Assert(err, qt.IsNil)
+}