Detect now invalid path patterns in cascade

Closes #11977

2 files changed, 31 insertions, 5 deletions

diff --git a/resources/page/page_matcher.go b/resources/page/page_matcher.go
index fbdb25d72..466b6fe53 100644
--- a/resources/page/page_matcher.go
+++ b/resources/page/page_matcher.go
@@ -18,6 +18,7 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/maps"
 	"github.com/gohugoio/hugo/config"
 	"github.com/gohugoio/hugo/hugofs/glob"
@@ -90,7 +91,14 @@ var disallowedCascadeKeys = map[string]bool{
 	"lang": true,
 }
 
-func DecodeCascadeConfig(in any) (*config.ConfigNamespace[[]PageMatcherParamsConfig, map[PageMatcher]maps.Params], error) {
+// See issue 11977.
+func isGlobWithExtension(s string) bool {
+	pathParts := strings.Split(s, "/")
+	last := pathParts[len(pathParts)-1]
+	return strings.Count(last, ".") > 0
+}
+
+func DecodeCascadeConfig(logger loggers.Logger, in any) (*config.ConfigNamespace[[]PageMatcherParamsConfig, map[PageMatcher]maps.Params], error) {
 	buildConfig := func(in any) (map[PageMatcher]maps.Params, any, error) {
 		cascade := make(map[PageMatcher]maps.Params)
 		if in == nil {
@@ -119,6 +127,9 @@ func DecodeCascadeConfig(in any) (*config.ConfigNamespace[[]PageMatcherParamsCon
 
 		for _, cfg := range cfgs {
 			m := cfg.Target
+			if isGlobWithExtension(m.Path) {
+				logger.Erroridf("cascade-pattern-with-extension", "cascade target path %q looks like a path with an extension; since Hugo v0.123.0 this will not match anything, see  https://gohugo.io/methods/page/path/", m.Path)
+			}
 			c, found := cascade[m]
 			if found {
 				// Merge
@@ -139,8 +150,8 @@ func DecodeCascadeConfig(in any) (*config.ConfigNamespace[[]PageMatcherParamsCon
 }
 
 // DecodeCascade decodes in which could be either a map or a slice of maps.
-func DecodeCascade(in any) (map[PageMatcher]maps.Params, error) {
-	conf, err := DecodeCascadeConfig(in)
+func DecodeCascade(logger loggers.Logger, in any) (map[PageMatcher]maps.Params, error) {
+	conf, err := DecodeCascadeConfig(logger, in)
 	if err != nil {
 		return nil, err
 	}
diff --git a/resources/page/page_matcher_test.go b/resources/page/page_matcher_test.go
index c27a2e9b2..e659eb3b5 100644
--- a/resources/page/page_matcher_test.go
+++ b/resources/page/page_matcher_test.go
@@ -18,6 +18,7 @@ import (
 	"testing"
 
 	"github.com/gohugoio/hugo/common/hugo"
+	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/common/maps"
 
 	qt "github.com/frankban/quicktest"
@@ -128,7 +129,7 @@ func TestDecodeCascadeConfig(t *testing.T) {
 		},
 	}
 
-	got, err := DecodeCascadeConfig(in)
+	got, err := DecodeCascadeConfig(loggers.NewDefault(), in)
 
 	c.Assert(err, qt.IsNil)
 	c.Assert(got, qt.IsNotNil)
@@ -150,7 +151,7 @@ func TestDecodeCascadeConfig(t *testing.T) {
 		{Params: maps.Params{"b": string("bv")}, Target: PageMatcher{Kind: "page"}},
 	})
 
-	got, err = DecodeCascadeConfig(nil)
+	got, err = DecodeCascadeConfig(loggers.NewDefault(), nil)
 	c.Assert(err, qt.IsNil)
 	c.Assert(got, qt.IsNotNil)
 }
@@ -172,3 +173,17 @@ func (c testConfig) Running() bool {
 func (c testConfig) WorkingDir() string {
 	return c.workingDir
 }
+
+func TestIsGlobWithExtension(t *testing.T) {
+	c := qt.New(t)
+
+	c.Assert(isGlobWithExtension("index.md"), qt.Equals, true)
+	c.Assert(isGlobWithExtension("foo/index.html"), qt.Equals, true)
+	c.Assert(isGlobWithExtension("posts/page"), qt.Equals, false)
+	c.Assert(isGlobWithExtension("pa.th/foo"), qt.Equals, false)
+	c.Assert(isGlobWithExtension(""), qt.Equals, false)
+	c.Assert(isGlobWithExtension("*.md?"), qt.Equals, true)
+	c.Assert(isGlobWithExtension("*.md*"), qt.Equals, true)
+	c.Assert(isGlobWithExtension("posts/*"), qt.Equals, false)
+	c.Assert(isGlobWithExtension("*.md"), qt.Equals, true)
+}