Rename taxonomy kinds from taxonomy to term, taxonomyTerm to taxonomy

And we have taken great measures to limit potential site breakage:

* For `disableKinds` and `outputs` we try to map from old to new values if possible, if not we print an ERROR that can be toggled off if not relevant.
* The layout lookup is mostly compatible with more options for the new `term` kind.

That leaves:

* Where queries in site.Pages using taxonomy/taxonomyTerm Kind values as filter.
* Other places where these kind value are used in the templates (classes etc.)

Fixes #6911
Fixes #7395

4 files changed, 24 insertions, 17 deletions

diff --git a/resources/page/page.go b/resources/page/page.go
index 934427b0e..de417178f 100644
--- a/resources/page/page.go
+++ b/resources/page/page.go
@@ -151,7 +151,7 @@ type PageMetaProvider interface {
 	// Configured keywords.
 	Keywords() []string
 
-	// The Page Kind. One of page, home, section, taxonomy, taxonomyTerm.
+	// The Page Kind. One of page, home, section, taxonomy, term.
 	Kind() string
 
 	// The configured layout to use to render this page. Typically set in front matter.
diff --git a/resources/page/page_kinds.go b/resources/page/page_kinds.go
index 1f59ec869..719375f66 100644
--- a/resources/page/page_kinds.go
+++ b/resources/page/page_kinds.go
@@ -20,18 +20,25 @@ const (
 
 	// The rest are node types; home page, sections etc.
 
-	KindHome         = "home"
-	KindSection      = "section"
-	KindTaxonomy     = "taxonomy"
-	KindTaxonomyTerm = "taxonomyTerm"
+	KindHome    = "home"
+	KindSection = "section"
+
+	// Note tha before Hugo 0.73 these were confusingly named
+	// taxonomy (now: term)
+	// taxonomyTerm (now: taxonomy)
+	KindTaxonomy = "taxonomy"
+	KindTerm     = "term"
 )
 
 var kindMap = map[string]string{
-	strings.ToLower(KindPage):         KindPage,
-	strings.ToLower(KindHome):         KindHome,
-	strings.ToLower(KindSection):      KindSection,
-	strings.ToLower(KindTaxonomy):     KindTaxonomy,
-	strings.ToLower(KindTaxonomyTerm): KindTaxonomyTerm,
+	strings.ToLower(KindPage):     KindPage,
+	strings.ToLower(KindHome):     KindHome,
+	strings.ToLower(KindSection):  KindSection,
+	strings.ToLower(KindTaxonomy): KindTaxonomy,
+	strings.ToLower(KindTerm):     KindTerm,
+
+	// Legacy, pre v0.53.0.
+	"taxonomyterm": KindTaxonomy,
 }
 
 // GetKind gets the page kind given a string, empty if not found.
diff --git a/resources/page/page_kinds_test.go b/resources/page/page_kinds_test.go
index 7fba7e1d2..8ad3493ee 100644
--- a/resources/page/page_kinds_test.go
+++ b/resources/page/page_kinds_test.go
@@ -27,9 +27,9 @@ func TestKind(t *testing.T) {
 	c.Assert(KindHome, qt.Equals, "home")
 	c.Assert(KindSection, qt.Equals, "section")
 	c.Assert(KindTaxonomy, qt.Equals, "taxonomy")
-	c.Assert(KindTaxonomyTerm, qt.Equals, "taxonomyTerm")
+	c.Assert(KindTerm, qt.Equals, "term")
 
-	c.Assert(GetKind("TAXONOMYTERM"), qt.Equals, KindTaxonomyTerm)
+	c.Assert(GetKind("TAXONOMYTERM"), qt.Equals, KindTaxonomy)
 	c.Assert(GetKind("Taxonomy"), qt.Equals, KindTaxonomy)
 	c.Assert(GetKind("Page"), qt.Equals, KindPage)
 	c.Assert(GetKind("Home"), qt.Equals, KindHome)
diff --git a/resources/page/page_paths_test.go b/resources/page/page_paths_test.go
index 4aaa41e8a..63df48a99 100644
--- a/resources/page/page_paths_test.go
+++ b/resources/page/page_paths_test.go
@@ -58,12 +58,12 @@ func TestPageTargetPath(t *testing.T) {
 						Sections: []string{"sect1"},
 						BaseName: "_index",
 						Type:     output.HTMLFormat}, TargetPaths{TargetFilename: "/sect1/index.html", SubResourceBaseTarget: "/sect1", Link: "/sect1/"}},
-					{"HTML taxonomy list", TargetPathDescriptor{
-						Kind:     KindTaxonomy,
+					{"HTML taxonomy term", TargetPathDescriptor{
+						Kind:     KindTerm,
 						Sections: []string{"tags", "hugo"},
 						BaseName: "_index",
 						Type:     output.HTMLFormat}, TargetPaths{TargetFilename: "/tags/hugo/index.html", SubResourceBaseTarget: "/tags/hugo", Link: "/tags/hugo/"}},
-					{"HTML taxonomy term", TargetPathDescriptor{
+					{"HTML taxonomy", TargetPathDescriptor{
 						Kind:     KindTaxonomy,
 						Sections: []string{"tags"},
 						BaseName: "_index",
@@ -143,8 +143,8 @@ func TestPageTargetPath(t *testing.T) {
 							Type:     output.HTMLFormat,
 							Addends:  "page/3"}, TargetPaths{TargetFilename: "/page/3/index.html", SubResourceBaseTarget: "/page/3", Link: "/page/3/"}},
 					{
-						"Paginated Taxonomy list", TargetPathDescriptor{
-							Kind:     KindTaxonomy,
+						"Paginated Taxonomy terms list", TargetPathDescriptor{
+							Kind:     KindTerm,
 							BaseName: "_index",
 							Sections: []string{"tags", "hugo"},
 							Type:     output.HTMLFormat,