Fix cascade-pattern-with-extension for cascade in site config

Also clean up the log handling in the integration tester, most notably lost logs during the config loading.

Fixes #12151

config/allconfig/allconfig.go

@@ -671,6 +671,13 @@ type Configs struct {
 	configLangs []config.AllProvider
 }
 
+func (c *Configs) Validate(logger loggers.Logger) error {
+	for p := range c.Base.Cascade.Config {
+		page.CheckCascadePattern(logger, p)
+	}
+	return nil
+}
+
 // transientErr returns the last transient error found during config compilation.
 func (c *Configs) transientErr() error {
 	for _, l := range c.LanguageConfigSlice {
@@ -969,7 +976,7 @@ func decodeConfigFromParams(fs afero.Fs, logger loggers.Logger, bcfg config.Base
 	})
 
 	for _, v := range decoderSetups {
-		p := decodeConfig{p: p, c: target, fs: fs, logger: logger, bcfg: bcfg}
+		p := decodeConfig{p: p, c: target, fs: fs, bcfg: bcfg}
 		if err := v.decode(v, p); err != nil {
 			return fmt.Errorf("failed to decode %q: %w", v.key, err)
 		}

config/allconfig/alldecoders.go

@@ -18,7 +18,6 @@ import (
 	"strings"
 
 	"github.com/gohugoio/hugo/cache/filecache"
-	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/common/types"
 	"github.com/gohugoio/hugo/config"
@@ -43,11 +42,10 @@ import (
 )
 
 type decodeConfig struct {
-	p      config.Provider
-	c      *Config
-	fs     afero.Fs
-	logger loggers.Logger
-	bcfg   config.BaseConfig
+	p    config.Provider
+	c    *Config
+	fs   afero.Fs
+	bcfg config.BaseConfig
 }
 
 type decodeWeight struct {
@@ -293,7 +291,7 @@ var allDecoderSetups = map[string]decodeWeight{
 		key: "cascade",
 		decode: func(d decodeWeight, p decodeConfig) error {
 			var err error
-			p.c.Cascade, err = page.DecodeCascadeConfig(p.logger, p.p.Get(d.key))
+			p.c.Cascade, err = page.DecodeCascadeConfig(nil, p.p.Get(d.key))
 			return err
 		},
 	},