Misc YAML adjustments

Closes #14067

Author: bep

common/maps/params.go

@@ -14,7 +14,9 @@
 package maps
 
 import (
+	"errors"
 	"fmt"
+	xmaps "maps"
 	"strings"
 
 	"github.com/spf13/cast"
@@ -101,7 +103,6 @@ func (p Params) merge(ps ParamsMergeStrategy, pp Params) {
 	noUpdate = noUpdate || (ps != "" && ps == ParamsMergeStrategyShallow)
 
 	for k, v := range pp {
-
 		if k == MergeStrategyKey {
 			continue
 		}
@@ -115,6 +116,9 @@ func (p Params) merge(ps ParamsMergeStrategy, pp Params) {
 				}
 			}
 		} else if !noUpdate {
+			if vvv, ok := v.(Params); ok {
+				v = xmaps.Clone(vvv)
+			}
 			p[k] = v
 		}
 
@@ -266,9 +270,17 @@ func CleanConfigStringMapString(m map[string]string) map[string]string {
 // CleanConfigStringMap is the same as CleanConfigStringMapString but for
 // map[string]any.
 func CleanConfigStringMap(m map[string]any) map[string]any {
+	return doCleanConfigStringMap(m, 0)
+}
+
+func doCleanConfigStringMap(m map[string]any, depth int) map[string]any {
 	if len(m) == 0 {
 		return m
 	}
+	const maxDepth = 1000
+	if depth > maxDepth {
+		panic(errors.New("max depth exceeded"))
+	}
 	if _, found := m[MergeStrategyKey]; !found {
 		return m
 	}
@@ -280,9 +292,9 @@ func CleanConfigStringMap(m map[string]any) map[string]any {
 		}
 		switch v2 := v.(type) {
 		case map[string]any:
-			m2[k] = CleanConfigStringMap(v2)
+			m2[k] = doCleanConfigStringMap(v2, depth+1)
 		case Params:
-			var p Params = CleanConfigStringMap(v2)
+			var p Params = doCleanConfigStringMap(v2, depth+1)
 			m2[k] = p
 		case map[string]string:
 			m2[k] = CleanConfigStringMapString(v2)

config/allconfig/allconfig.go

@@ -56,7 +56,7 @@ import (
 	"github.com/gohugoio/hugo/resources/page/pagemeta"
 	"github.com/spf13/afero"
 
-	xmaps "golang.org/x/exp/maps"
+	xmaps "maps"
 )
 
 // InternalConfig is the internal configuration for Hugo, not read from any user provided config file.
@@ -1054,6 +1054,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 		mergedConfig := config.New()
 		var differentRootKeys []string
 		switch x := v.(type) {
+		case nil:
 		case maps.Params:
 			_, found := x["params"]
 			if !found {
@@ -1129,6 +1130,7 @@ func fromLoadConfigResult(fs afero.Fs, logger loggers.Logger, res config.LoadCon
 
 			langConfigMap[k] = clone
 		case maps.ParamsMergeStrategy:
+
 		default:
 			panic(fmt.Sprintf("unknown type in languages config: %T", v))
 

config/allconfig/load.go

@@ -40,7 +40,13 @@ import (
 //lint:ignore ST1005 end user message.
 var ErrNoConfigFile = errors.New("Unable to locate config file or config directory. Perhaps you need to create a new site.\n       Run `hugo help new` for details.\n")
 
-func LoadConfig(d ConfigSourceDescriptor) (*Configs, error) {
+func LoadConfig(d ConfigSourceDescriptor) (configs *Configs, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = fmt.Errorf("failed to load config: %v", r)
+		}
+	}()
+
 	if len(d.Environ) == 0 && !hugo.IsRunningAsTest() {
 		d.Environ = os.Environ()
 	}
@@ -59,7 +65,7 @@ func LoadConfig(d ConfigSourceDescriptor) (*Configs, error) {
 		return nil, fmt.Errorf("failed to load config: %w", err)
 	}
 
-	configs, err := fromLoadConfigResult(d.Fs, d.Logger, res)
+	configs, err = fromLoadConfigResult(d.Fs, d.Logger, res)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create config from result: %w", err)
 	}
@@ -93,7 +99,7 @@ func LoadConfig(d ConfigSourceDescriptor) (*Configs, error) {
 
 	loggers.SetGlobalLogger(d.Logger)
 
-	return configs, nil
+	return
 }
 
 // ConfigSourceDescriptor describes where to find the config (e.g. config.toml etc.).
@@ -538,11 +544,12 @@ func (l configLoader) loadConfig(configName string) (string, error) {
 	return filename, nil
 }
 
-func (l configLoader) deleteMergeStrategies() {
+func (l configLoader) deleteMergeStrategies() (err error) {
 	l.cfg.WalkParams(func(params ...maps.KeyParams) bool {
 		params[len(params)-1].Params.DeleteMergeStrategy()
 		return false
 	})
+	return
 }
 
 func (l configLoader) wrapFileError(err error, filename string) error {

config/defaultConfigProvider.go

@@ -14,11 +14,13 @@
 package config
 
 import (
+	"errors"
 	"fmt"
+	"slices"
 	"strings"
 	"sync"
 
-	xmaps "golang.org/x/exp/maps"
+	xmaps "maps"
 
 	"github.com/spf13/cast"
 
@@ -237,12 +239,16 @@ func (c *defaultConfigProvider) Merge(k string, v any) {
 func (c *defaultConfigProvider) Keys() []string {
 	c.mu.RLock()
 	defer c.mu.RUnlock()
-	return xmaps.Keys(c.root)
+	return slices.Collect(xmaps.Keys(c.root))
 }
 
 func (c *defaultConfigProvider) WalkParams(walkFn func(params ...maps.KeyParams) bool) {
-	var walk func(params ...maps.KeyParams)
-	walk = func(params ...maps.KeyParams) {
+	maxDepth := 1000
+	var walk func(depth int, params ...maps.KeyParams)
+	walk = func(depth int, params ...maps.KeyParams) {
+		if depth > maxDepth {
+			panic(errors.New("max depth exceeded"))
+		}
 		if walkFn(params...) {
 			return
 		}
@@ -253,11 +259,11 @@ func (c *defaultConfigProvider) WalkParams(walkFn func(params ...maps.KeyParams)
 				paramsplus1 := make([]maps.KeyParams, i+1)
 				copy(paramsplus1, params)
 				paramsplus1[i] = maps.KeyParams{Key: k, Params: p2}
-				walk(paramsplus1...)
+				walk(depth+1, paramsplus1...)
 			}
 		}
 	}
-	walk(maps.KeyParams{Key: "", Params: c.root})
+	walk(0, maps.KeyParams{Key: "", Params: c.root})
 }
 
 func (c *defaultConfigProvider) determineMergeStrategy(params ...maps.KeyParams) maps.ParamsMergeStrategy {

go.mod

@@ -75,7 +75,6 @@ require (
 	github.com/yuin/goldmark-emoji v1.0.6
 	go.uber.org/automaxprocs v1.5.3
 	gocloud.dev v0.43.0
-	golang.org/x/exp v0.0.0-20250819193227-8b4c13bb791b
 	golang.org/x/image v0.32.0
 	golang.org/x/mod v0.29.0
 	golang.org/x/net v0.46.0

go.sum

@@ -267,8 +267,6 @@ github.com/gobwas/glob v0.2.3 h1:A4xDbljILXROh+kObIiy5kIaPYD8e96x1tgBhUI5J+Y=
 github.com/gobwas/glob v0.2.3/go.mod h1:d3Ez4x06l9bZtSvzIay5+Yzi0fmZzPgnTbPcKjJAkT8=
 github.com/goccy/go-yaml v1.18.0 h1:8W7wMFS12Pcas7KU+VVkaiCng+kG8QiFeFwzFb+rwuw=
 github.com/goccy/go-yaml v1.18.0/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
-github.com/gohugoio/go-i18n/v2 v2.1.3-0.20251018141905-f04b60c79bd1 h1:95D/7I2Vv3N9icWWlayjoxp7rSzjcr6PaGXLw8DZzgY=
-github.com/gohugoio/go-i18n/v2 v2.1.3-0.20251018141905-f04b60c79bd1/go.mod h1:m5hu1im5Qc7LDycVLvee6MPobJiRLBYHklypFJR0/aE=
 github.com/gohugoio/go-i18n/v2 v2.1.3-0.20251018145728-cfcc22d823c6 h1:pxlAea9eRwuAnt/zKbGqlFO2ZszpIe24YpOVLf+N+4I=
 github.com/gohugoio/go-i18n/v2 v2.1.3-0.20251018145728-cfcc22d823c6/go.mod h1:m5hu1im5Qc7LDycVLvee6MPobJiRLBYHklypFJR0/aE=
 github.com/gohugoio/hashstructure v0.6.0 h1:7wMB/2CfXoThFYhdWRGv3u3rUM761Cq29CxUW+NltUg=
@@ -594,8 +592,6 @@ golang.org/x/exp v0.0.0-20191227195350-da58074b4299/go.mod h1:2RIsYlXP63K8oxa1u0
 golang.org/x/exp v0.0.0-20200119233911-0405dc783f0a/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EHIKF9dgMWnmCNThgcyBT1FY9mM=
 golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6/go.mod h1:3jZMyOhIsHpP37uCMkUooju7aAi5cS1Q23tOzKc+0MU=
-golang.org/x/exp v0.0.0-20250819193227-8b4c13bb791b h1:DXr+pvt3nC887026GRP39Ej11UATqWDmWuS99x26cD0=
-golang.org/x/exp v0.0.0-20250819193227-8b4c13bb791b/go.mod h1:4QTo5u+SEIbbKW1RacMZq1YEfOBqeXa19JeshGi+zc4=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
 golang.org/x/image v0.0.0-20210220032944-ac19c3e999fb/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=

hugolib/config_test.go

@@ -1570,3 +1570,82 @@ title: "P1 us"
 `
 	Test(t, files)
 }
+
+func TestConfigYAMLAnchorsMerge(t *testing.T) {
+	t.Parallel()
+
+	files := `
+-- hugo.yaml --
+definitions:
+  params: &params
+    p1: p1alias
+
+theme: "mytheme"
+defaultContentLanguage: en
+defaultContentLanguageInSubdir: true
+
+params:
+    <<: *params
+
+languages:
+  en:
+    weight: 1
+  no:
+    weight: 2
+    params:
+      <<: *params
+      p2: p2no
+  sv:
+    weight: 3
+    params: *params
+     
+-- layouts/all.html --
+Params: {{ site.Params }}|
+-- themes/mytheme/hugo.yaml --
+definitions:
+  params: &params
+    p1: p1aliastheme
+    p2: p2aliastheme
+
+params: *params
+ 
+  
+`
+	b := Test(t, files)
+
+	b.AssertFileContent("public/en/index.html", "Params: map[p1:p1alias p2:p2aliastheme]|")
+	b.AssertFileContent("public/no/index.html", "Params: map[p1:p1alias p2:p2no]|")
+	b.AssertFileContent("public/sv/index.html", "Params: map[p1:p1alias p2:p2aliastheme]|")
+}
+
+func TestConfigYAMLAnchorsCyclicReference(t *testing.T) {
+	t.Parallel()
+
+	files := `
+-- hugo.yaml --
+definitions:
+  params: &params
+    p1: p1alias
+
+params:
+    p3: *params
+
+languages:
+  en:
+    weight: 1
+  sv:
+    weight: 2
+    params: *params
+     
+-- layouts/all.html --
+Params: {{ site.Params }}|
+
+`
+
+	for range 3 {
+		b := Test(t, files)
+		b.AssertFileContent("public/index.html", "Params: map[p3:map[p1:p1alias]]|")
+		b.AssertFileContent("public/sv/index.html", "Params: map[p1:p1alias p3:map[p1:p1alias]]|")
+
+	}
+}

hugolib/page__meta.go

@@ -21,11 +21,12 @@ import (
 	"strings"
 	"time"
 
+	xmaps "maps"
+
 	"github.com/bep/logg"
 	"github.com/gobuffalo/flect"
 	"github.com/gohugoio/hugo/langs"
 	"github.com/gohugoio/hugo/markup/converter"
-	xmaps "golang.org/x/exp/maps"
 
 	"github.com/gohugoio/hugo/source"
 

hugolib/site.go

@@ -23,6 +23,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"sort"
 	"strings"
 	"sync"
@@ -48,9 +49,10 @@ import (
 	"github.com/gohugoio/hugo/modules"
 	"github.com/gohugoio/hugo/resources"
 
+	xmaps "maps"
+
 	"github.com/gohugoio/hugo/tpl/tplimpl"
 	"github.com/gohugoio/hugo/tpl/tplimplinit"
-	xmaps "golang.org/x/exp/maps"
 
 	// Loads the template funcs namespaces.
 
@@ -999,7 +1001,7 @@ func (w *WhatChanged) Changes() []identity.Identity {
 	if w == nil || w.ids == nil {
 		return nil
 	}
-	return xmaps.Keys(w.ids)
+	return slices.Collect(xmaps.Keys(w.ids))
 }
 
 func (w *WhatChanged) Drain() []identity.Identity {

navigation/menu.go

@@ -16,6 +16,7 @@ package navigation
 
 import (
 	"html/template"
+	"slices"
 	"sort"
 
 	"github.com/gohugoio/hugo/common/maps"
@@ -25,7 +26,6 @@ import (
 	"github.com/mitchellh/mapstructure"
 
 	"github.com/spf13/cast"
-	"slices"
 )
 
 var smc = newMenuCache()