Fix live reload when editing inline partials

Fixes #13723

tpl/internal/go_templates/htmltemplate/hugo_template.go

@@ -15,6 +15,7 @@ package template
 
 import (
 	"fmt"
+	"iter"
 
 	"github.com/gohugoio/hugo/common/types"
 	template "github.com/gohugoio/hugo/tpl/internal/go_templates/texttemplate"
@@ -38,6 +39,19 @@ func (t *Template) Prepare() (*template.Template, error) {
 	return t.text, nil
 }
 
+func (t *Template) All() iter.Seq[*Template] {
+	return func(yield func(t *Template) bool) {
+		ns := t.nameSpace
+		ns.mu.Lock()
+		defer ns.mu.Unlock()
+		for _, v := range ns.set {
+			if !yield(v) {
+				return
+			}
+		}
+	}
+}
+
 // See https://github.com/golang/go/issues/5884
 func StripTags(html string) string {
 	return stripTags(html)

tpl/internal/go_templates/texttemplate/hugo_template.go

@@ -17,6 +17,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"iter"
 	"reflect"
 
 	"github.com/gohugoio/hugo/common/herrors"
@@ -433,3 +434,18 @@ func (s *state) evalCall(dot, fun reflect.Value, isBuiltin bool, node parse.Node
 func isTrue(val reflect.Value) (truth, ok bool) {
 	return hreflect.IsTruthfulValue(val), true
 }
+
+func (t *Template) All() iter.Seq[*Template] {
+	return func(yield func(t *Template) bool) {
+		if t.common == nil {
+			return
+		}
+		t.muTmpl.RLock()
+		defer t.muTmpl.RUnlock()
+		for _, v := range t.tmpl {
+			if !yield(v) {
+				return
+			}
+		}
+	}
+}

tpl/internal/go_templates/texttemplate/parse/parse.go

@@ -533,7 +533,7 @@ func (t *Tree) parseControl(context string) (pos Pos, line int, pipe *PipeNode,
 		t.rangeDepth--
 	}
 	switch next.Type() {
-	case nodeEnd: //done
+	case nodeEnd: // done
 	case nodeElse:
 		// Special case for "else if" and "else with".
 		// If the "else" is followed immediately by an "if" or "with",

tpl/tplimpl/templates.go

@@ -2,6 +2,7 @@ package tplimpl
 
 import (
 	"io"
+	"iter"
 	"regexp"
 	"strconv"
 	"strings"
@@ -44,16 +45,15 @@ var embeddedTemplatesAliases = map[string][]string{
 	"_shortcodes/twitter.html": {"_shortcodes/tweet.html"},
 }
 
-func (s *TemplateStore) parseTemplate(ti *TemplInfo) error {
-	err := s.tns.doParseTemplate(ti)
+func (s *TemplateStore) parseTemplate(ti *TemplInfo, replace bool) error {
+	err := s.tns.doParseTemplate(ti, replace)
 	if err != nil {
 		return s.addFileContext(ti, "parse of template failed", err)
 	}
-
 	return err
 }
 
-func (t *templateNamespace) doParseTemplate(ti *TemplInfo) error {
+func (t *templateNamespace) doParseTemplate(ti *TemplInfo, replace bool) error {
 	if !ti.noBaseOf || ti.category == CategoryBaseof {
 		// Delay parsing until we have the base template.
 		return nil
@@ -68,7 +68,7 @@ func (t *templateNamespace) doParseTemplate(ti *TemplInfo) error {
 
 	if ti.D.IsPlainText {
 		prototype := t.parseText
-		if prototype.Lookup(name) != nil {
+		if !replace && prototype.Lookup(name) != nil {
 			name += "-" + strconv.FormatUint(t.nameCounter.Add(1), 10)
 		}
 		templ, err = prototype.New(name).Parse(ti.content)
@@ -77,7 +77,7 @@ func (t *templateNamespace) doParseTemplate(ti *TemplInfo) error {
 		}
 	} else {
 		prototype := t.parseHTML
-		if prototype.Lookup(name) != nil {
+		if !replace && prototype.Lookup(name) != nil {
 			name += "-" + strconv.FormatUint(t.nameCounter.Add(1), 10)
 		}
 		templ, err = prototype.New(name).Parse(ti.content)
@@ -181,19 +181,24 @@ func (t *templateNamespace) applyBaseTemplate(overlay *TemplInfo, base keyTempla
 	return nil
 }
 
-func (t *templateNamespace) templatesIn(in tpl.Template) []tpl.Template {
-	var templs []tpl.Template
-	if textt, ok := in.(*texttemplate.Template); ok {
-		for _, t := range textt.Templates() {
-			templs = append(templs, t)
+func (t *templateNamespace) templatesIn(in tpl.Template) iter.Seq[tpl.Template] {
+	return func(yield func(t tpl.Template) bool) {
+		switch in := in.(type) {
+		case *htmltemplate.Template:
+			for t := range in.All() {
+				if !yield(t) {
+					return
+				}
+			}
+
+		case *texttemplate.Template:
+			for t := range in.All() {
+				if !yield(t) {
+					return
+				}
+			}
 		}
 	}
-	if htmlt, ok := in.(*htmltemplate.Template); ok {
-		for _, t := range htmlt.Templates() {
-			templs = append(templs, t)
-		}
-	}
-	return templs
 }
 
 /*
@@ -337,8 +342,6 @@ func (t *templateNamespace) createPrototypes(init bool) error {
 		t.prototypeHTML = htmltemplate.Must(t.parseHTML.Clone())
 		t.prototypeText = texttemplate.Must(t.parseText.Clone())
 	}
-	// t.execHTML = htmltemplate.Must(t.parseHTML.Clone())
-	// t.execText = texttemplate.Must(t.parseText.Clone())
 
 	return nil
 }
@@ -350,3 +353,14 @@ func newTemplateNamespace(funcs map[string]any) *templateNamespace {
 		standaloneText: texttemplate.New("").Funcs(funcs),
 	}
 }
+
+func isText(t tpl.Template) bool {
+	switch t.(type) {
+	case *texttemplate.Template:
+		return true
+	case *htmltemplate.Template:
+		return false
+	default:
+		panic("unknown template type")
+	}
+}

tpl/tplimpl/templatestore.go

@@ -114,17 +114,18 @@ func NewStore(opts StoreOptions, siteOpts SiteOptions) (*TemplateStore, error) {
 		panic("HTML output format not found")
 	}
 	s := &TemplateStore{
-		opts:                opts,
-		siteOpts:            siteOpts,
-		optsOrig:            opts,
-		siteOptsOrig:        siteOpts,
-		htmlFormat:          html,
-		storeSite:           configureSiteStorage(siteOpts, opts.Watching),
-		treeMain:            doctree.NewSimpleTree[map[nodeKey]*TemplInfo](),
-		treeShortcodes:      doctree.NewSimpleTree[map[string]map[TemplateDescriptor]*TemplInfo](),
-		templatesByPath:     maps.NewCache[string, *TemplInfo](),
-		shortcodesByName:    maps.NewCache[string, *TemplInfo](),
-		cacheLookupPartials: maps.NewCache[string, *TemplInfo](),
+		opts:                 opts,
+		siteOpts:             siteOpts,
+		optsOrig:             opts,
+		siteOptsOrig:         siteOpts,
+		htmlFormat:           html,
+		storeSite:            configureSiteStorage(siteOpts, opts.Watching),
+		treeMain:             doctree.NewSimpleTree[map[nodeKey]*TemplInfo](),
+		treeShortcodes:       doctree.NewSimpleTree[map[string]map[TemplateDescriptor]*TemplInfo](),
+		templatesByPath:      maps.NewCache[string, *TemplInfo](),
+		shortcodesByName:     maps.NewCache[string, *TemplInfo](),
+		cacheLookupPartials:  maps.NewCache[string, *TemplInfo](),
+		templatesSnapshotSet: maps.NewCache[*parse.Tree, struct{}](),
 
 		// Note that the funcs passed below is just for name validation.
 		tns: newTemplateNamespace(siteOpts.TemplateFuncs),
@@ -143,10 +144,10 @@ func NewStore(opts StoreOptions, siteOpts SiteOptions) (*TemplateStore, error) {
 	if err := s.insertEmbedded(); err != nil {
 		return nil, err
 	}
-	if err := s.parseTemplates(); err != nil {
+	if err := s.parseTemplates(false); err != nil {
 		return nil, err
 	}
-	if err := s.extractInlinePartials(); err != nil {
+	if err := s.extractInlinePartials(false); err != nil {
 		return nil, err
 	}
 	if err := s.transformTemplates(); err != nil {
@@ -424,10 +425,11 @@ type TemplateStore struct {
 	siteOpts   SiteOptions
 	htmlFormat output.Format
 
-	treeMain         *doctree.SimpleTree[map[nodeKey]*TemplInfo]
-	treeShortcodes   *doctree.SimpleTree[map[string]map[TemplateDescriptor]*TemplInfo]
-	templatesByPath  *maps.Cache[string, *TemplInfo]
-	shortcodesByName *maps.Cache[string, *TemplInfo]
+	treeMain             *doctree.SimpleTree[map[nodeKey]*TemplInfo]
+	treeShortcodes       *doctree.SimpleTree[map[string]map[TemplateDescriptor]*TemplInfo]
+	templatesByPath      *maps.Cache[string, *TemplInfo]
+	shortcodesByName     *maps.Cache[string, *TemplInfo]
+	templatesSnapshotSet *maps.Cache[*parse.Tree, struct{}]
 
 	dh descriptorHandler
 
@@ -709,12 +711,16 @@ func (s *TemplateStore) RefreshFiles(include func(fi hugofs.FileMetaInfo) bool)
 	if err := s.insertTemplates(include, true); err != nil {
 		return err
 	}
-	if err := s.parseTemplates(); err != nil {
+	if err := s.createTemplatesSnapshot(); err != nil {
 		return err
 	}
-	if err := s.extractInlinePartials(); err != nil {
+	if err := s.parseTemplates(true); err != nil {
 		return err
 	}
+	if err := s.extractInlinePartials(true); err != nil {
+		return err
+	}
+
 	if err := s.transformTemplates(); err != nil {
 		return err
 	}
@@ -940,59 +946,77 @@ func (s *TemplateStore) extractIdentifiers(line string) []string {
 	return identifiers
 }
 
-func (s *TemplateStore) extractInlinePartials() error {
+func (s *TemplateStore) extractInlinePartials(rebuild bool) error {
 	isPartialName := func(s string) bool {
 		return strings.HasPrefix(s, "partials/") || strings.HasPrefix(s, "_partials/")
 	}
 
-	p := s.tns
 	// We may find both inline and external partials in the current template namespaces,
 	// so only add the ones we have not seen before.
-	addIfNotSeen := func(isText bool, templs ...tpl.Template) error {
-		for _, templ := range templs {
-			if templ.Name() == "" || !isPartialName(templ.Name()) {
-				continue
-			}
-			name := templ.Name()
-			if !paths.HasExt(name) {
-				// Assume HTML. This in line with how the lookup works.
-				name = name + s.htmlFormat.MediaType.FirstSuffix.FullSuffix
-			}
-			if !strings.HasPrefix(name, "_") {
-				name = "_" + name
-			}
-			pi := s.opts.PathParser.Parse(files.ComponentFolderLayouts, name)
-			ti, err := s.insertTemplate(pi, nil, false, s.treeMain)
-			if err != nil {
-				return err
-			}
-
-			if ti != nil {
-				ti.Template = templ
-				ti.noBaseOf = true
-				ti.subCategory = SubCategoryInline
-				ti.D.IsPlainText = isText
-			}
-
+	for templ := range s.allRawTemplates() {
+		if templ.Name() == "" || !isPartialName(templ.Name()) {
+			continue
 		}
-		return nil
-	}
-	addIfNotSeen(false, p.templatesIn(p.parseHTML)...)
-	addIfNotSeen(true, p.templatesIn(p.parseText)...)
-
-	for _, t := range p.baseofHtmlClones {
-		if err := addIfNotSeen(false, p.templatesIn(t)...); err != nil {
+		if rebuild && s.templatesSnapshotSet.Contains(getParseTree(templ)) {
+			// This partial was not created during this build.
+			continue
+		}
+		name := templ.Name()
+		if !paths.HasExt(name) {
+			// Assume HTML. This in line with how the lookup works.
+			name = name + s.htmlFormat.MediaType.FirstSuffix.FullSuffix
+		}
+		if !strings.HasPrefix(name, "_") {
+			name = "_" + name
+		}
+		pi := s.opts.PathParser.Parse(files.ComponentFolderLayouts, name)
+		ti, err := s.insertTemplate(pi, nil, SubCategoryInline, false, s.treeMain)
+		if err != nil {
 			return err
 		}
-	}
-	for _, t := range p.baseofTextClones {
-		if err := addIfNotSeen(true, p.templatesIn(t)...); err != nil {
-			return err
+
+		if ti != nil {
+			ti.Template = templ
+			ti.noBaseOf = true
+			ti.subCategory = SubCategoryInline
+			ti.D.IsPlainText = isText(templ)
 		}
 	}
+
 	return nil
 }
 
+func (s *TemplateStore) allRawTemplates() iter.Seq[tpl.Template] {
+	p := s.tns
+	return func(yield func(tpl.Template) bool) {
+		for t := range p.templatesIn(p.parseHTML) {
+			if !yield(t) {
+				return
+			}
+		}
+		for t := range p.templatesIn(p.parseText) {
+			if !yield(t) {
+				return
+			}
+		}
+
+		for _, tt := range p.baseofHtmlClones {
+			for t := range p.templatesIn(tt) {
+				if !yield(t) {
+					return
+				}
+			}
+		}
+		for _, tt := range p.baseofTextClones {
+			for t := range p.templatesIn(tt) {
+				if !yield(t) {
+					return
+				}
+			}
+		}
+	}
+}
+
 func (s *TemplateStore) insertEmbedded() error {
 	return fs.WalkDir(embeddedTemplatesFs, ".", func(path string, d fs.DirEntry, err error) error {
 		if err != nil {
@@ -1024,7 +1048,7 @@ func (s *TemplateStore) insertEmbedded() error {
 					return err
 				}
 			} else {
-				ti, err = s.insertTemplate(pi, nil, false, s.treeMain)
+				ti, err = s.insertTemplate(pi, nil, SubCategoryEmbedded, false, s.treeMain)
 				if err != nil {
 					return err
 				}
@@ -1105,7 +1129,7 @@ func (s *TemplateStore) insertShortcode(pi *paths.Path, fi hugofs.FileMetaInfo,
 	return ti, nil
 }
 
-func (s *TemplateStore) insertTemplate(pi *paths.Path, fi hugofs.FileMetaInfo, replace bool, tree doctree.Tree[map[nodeKey]*TemplInfo]) (*TemplInfo, error) {
+func (s *TemplateStore) insertTemplate(pi *paths.Path, fi hugofs.FileMetaInfo, subCategory SubCategory, replace bool, tree doctree.Tree[map[nodeKey]*TemplInfo]) (*TemplInfo, error) {
 	key, _, category, d, err := s.toKeyCategoryAndDescriptor(pi)
 	// See #13577. Warn for now.
 	if err != nil {
@@ -1119,7 +1143,7 @@ func (s *TemplateStore) insertTemplate(pi *paths.Path, fi hugofs.FileMetaInfo, r
 		return nil, nil
 	}
 
-	return s.insertTemplate2(pi, fi, key, category, d, replace, false, tree)
+	return s.insertTemplate2(pi, fi, key, category, subCategory, d, replace, false, tree)
 }
 
 func (s *TemplateStore) insertTemplate2(
@@ -1127,6 +1151,7 @@ func (s *TemplateStore) insertTemplate2(
 	fi hugofs.FileMetaInfo,
 	key string,
 	category Category,
+	subCategory SubCategory,
 	d TemplateDescriptor,
 	replace, isLegacyMapped bool,
 	tree doctree.Tree[map[nodeKey]*TemplInfo],
@@ -1160,6 +1185,11 @@ func (s *TemplateStore) insertTemplate2(
 		replace = fi.Meta().ModuleOrdinal < nkExisting.Fi.Meta().ModuleOrdinal
 	}
 
+	if !replace && existingFound {
+		// Always replace inline partials to allow for reloading.
+		replace = subCategory == SubCategoryInline && nkExisting.subCategory == SubCategoryInline
+	}
+
 	if !replace && existingFound {
 		if len(pi.Identifiers()) >= len(nkExisting.PathInfo.Identifiers()) {
 			// e.g. /pages/home.foo.html and  /pages/home.html where foo may be a valid language name in another site.
@@ -1190,7 +1220,7 @@ func (s *TemplateStore) insertTemplate2(
 	return ti, nil
 }
 
-func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) bool, replace bool) error {
+func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) bool, partialRebuild bool) error {
 	if include == nil {
 		include = func(fi hugofs.FileMetaInfo) bool {
 			return true
@@ -1372,7 +1402,7 @@ func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) boo
 
 		}
 
-		if replace && pi.NameNoIdentifier() == baseNameBaseof {
+		if partialRebuild && pi.NameNoIdentifier() == baseNameBaseof {
 			// A baseof file has changed.
 			resetBaseVariants = true
 		}
@@ -1380,12 +1410,12 @@ func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) boo
 		var ti *TemplInfo
 		var err error
 		if pi.Type() == paths.TypeShortcode {
-			ti, err = s.insertShortcode(pi, fi, replace, s.treeShortcodes)
+			ti, err = s.insertShortcode(pi, fi, partialRebuild, s.treeShortcodes)
 			if err != nil || ti == nil {
 				return err
 			}
 		} else {
-			ti, err = s.insertTemplate(pi, fi, replace, s.treeMain)
+			ti, err = s.insertTemplate(pi, fi, SubCategoryMain, partialRebuild, s.treeMain)
 			if err != nil || ti == nil {
 				return err
 			}
@@ -1419,7 +1449,7 @@ func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) boo
 		desc.IsPlainText = outputFormat.IsPlainText
 		desc.MediaType = mediaType.Type
 
-		ti, err := s.insertTemplate2(pi, fi, targetPath, category, desc, true, true, s.treeMain)
+		ti, err := s.insertTemplate2(pi, fi, targetPath, category, SubCategoryMain, desc, true, true, s.treeMain)
 		if err != nil {
 			return err
 		}
@@ -1430,6 +1460,7 @@ func (s *TemplateStore) insertTemplates(include func(fi hugofs.FileMetaInfo) boo
 		if err := s.tns.readTemplateInto(ti); err != nil {
 			return err
 		}
+
 	}
 
 	if resetBaseVariants {
@@ -1456,7 +1487,15 @@ func (s *TemplateStore) key(dir string) string {
 	return paths.TrimTrailing(dir)
 }
 
-func (s *TemplateStore) parseTemplates() error {
+func (s *TemplateStore) createTemplatesSnapshot() error {
+	s.templatesSnapshotSet.Reset()
+	for t := range s.allRawTemplates() {
+		s.templatesSnapshotSet.Set(getParseTree(t), struct{}{})
+	}
+	return nil
+}
+
+func (s *TemplateStore) parseTemplates(replace bool) error {
 	if err := func() error {
 		// Read and parse all templates.
 		for _, v := range s.treeMain.All() {
@@ -1464,7 +1503,7 @@ func (s *TemplateStore) parseTemplates() error {
 				if vv.state == processingStateTransformed {
 					continue
 				}
-				if err := s.parseTemplate(vv); err != nil {
+				if err := s.parseTemplate(vv, replace); err != nil {
 					return err
 				}
 			}
@@ -1484,7 +1523,7 @@ func (s *TemplateStore) parseTemplates() error {
 						// The regular expression used to detect if a template needs a base template has some
 						// rare false positives. Assume we don't need one.
 						vv.noBaseOf = true
-						if err := s.parseTemplate(vv); err != nil {
+						if err := s.parseTemplate(vv, replace); err != nil {
 							return err
 						}
 						continue
@@ -1513,7 +1552,7 @@ func (s *TemplateStore) parseTemplates() error {
 				if vvv.state == processingStateTransformed {
 					continue
 				}
-				if err := s.parseTemplate(vvv); err != nil {
+				if err := s.parseTemplate(vvv, replace); err != nil {
 					return err
 				}
 			}