Fix false path warnings with resources.PostProcess

Fixes gohugoio#7735

hugofs/createcounting_fs.go

@@ -31,6 +31,7 @@ type Reseter interface {
 // DuplicatesReporter reports about duplicate filenames.
 type DuplicatesReporter interface {
 	ReportDuplicates() string
+	Stop()
 }
 
 var (
@@ -67,11 +68,19 @@ func (c *createCountingFs) ReportDuplicates() string {
 	return strings.Join(dupes, ", ")
 }
 
+func (c *createCountingFs) Stop() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.stopped = true
+}
+
 // createCountingFs counts filenames of created files or files opened
 // for writing.
 type createCountingFs struct {
 	afero.Fs
 
+	stopped bool
+
 	mu        sync.Mutex
 	fileCount map[string]int
 }
@@ -86,6 +95,9 @@ func (c *createCountingFs) Reset() {
 func (fs *createCountingFs) onCreate(filename string) {
 	fs.mu.Lock()
 	defer fs.mu.Unlock()
+	if fs.stopped {
+		return
+	}
 
 	fs.fileCount[filename] = fs.fileCount[filename] + 1
 }

hugolib/hugo_sites_build.go

@@ -317,6 +317,14 @@ func (h *HugoSites) render(l logg.LevelLogger, config *BuildCfg) error {
 func (h *HugoSites) postProcess(l logg.LevelLogger) error {
 	defer h.timeTrack(l, time.Now(), "postProcess")
 
+	hugofs.WalkFilesystems(h.Fs.PublishDir, func(fs afero.Fs) bool {
+		if dfs, ok := fs.(hugofs.DuplicatesReporter); ok {
+			// We will rewrite to the same files, so we need to stop any duplicate counting.
+			dfs.Stop()
+		}
+		return false
+	})
+
 	// Make sure to write any build stats to disk first so it's available
 	// to the post processors.
 	if err := h.writeBuildStats(); err != nil {

testscripts/unfinished/hugo__path-warnings.txt

@@ -0,0 +1,22 @@
+
+
+hugo --printPathWarnings
+
+! stdout 'Duplicate target paths'
+
+-- hugo.toml --
+-- assets/css/styles.css --
+body {
+  background-color: #000;
+}
+-- content/p1.md --
+-- content/p2.md --
+-- content/p3.md --
+-- layouts/index.html --
+Home.
+-- layouts/_default/single.html --
+{{ $css := resources.Get "css/styles.css" }}
+{{ $css := $css | minify | fingerprint | resources.PostProcess  }}
+CSS: {{ $css.RelPermalink }}
+{{ .Title }}
+