hugolib: Normalize permalink path segments

When constructing permalinks, ensure that most inputs used as path
segments are normalized with PathSpec.MakeSegment instead of
PathSpec.URLize.

The primary exception to that rule is with taxonomy titles in
pageToPermalinkTitle(). The approach taken here is to use URLize for
taxonomy pages. Everything else will use MakeSegment. The reason for
this exception is that people use taxonomies such as "s1/p1" to generate
URLs precisely they way they wish (see gohugoio#5223). Tests have been added to
check for this case.

Fixes gohugoio#4926

hugolib/permalinks.go

@@ -152,9 +152,13 @@ func pageToPermalinkDate(p *Page, dateField string) (string, error) {
 
 // pageToPermalinkTitle returns the URL-safe form of the title
 func pageToPermalinkTitle(p *Page, _ string) (string, error) {
-	// Page contains Node which has Title
-	// (also contains URLPath which has Slug, sometimes)
-	return p.s.PathSpec.URLize(p.title), nil
+	if p.Kind == "taxonomy" {
+		// Taxonomies are allowed to have '/' characters, so don't normalize
+		// them with MakeSegment.
+		return p.s.PathSpec.URLize(p.title), nil
+	}
+
+	return p.s.PathSpec.MakeSegment(p.title), nil
 }
 
 // pageToPermalinkFilename returns the URL-safe form of the filename
@@ -166,7 +170,7 @@ func pageToPermalinkFilename(p *Page, _ string) (string, error) {
 		_, name = filepath.Split(dir)
 	}
 
-	return p.s.PathSpec.URLize(name), nil
+	return p.s.PathSpec.MakeSegment(name), nil
 }
 
 // if the page has a slug, return the slug, else return the title
@@ -181,20 +185,30 @@ func pageToPermalinkSlugElseTitle(p *Page, a string) (string, error) {
 		if strings.HasSuffix(p.Slug, "-") {
 			p.Slug = p.Slug[0 : len(p.Slug)-1]
 		}
-		return p.s.PathSpec.URLize(p.Slug), nil
+		return p.s.PathSpec.MakeSegment(p.Slug), nil
 	}
 	return pageToPermalinkTitle(p, a)
 }
 
 func pageToPermalinkSection(p *Page, _ string) (string, error) {
 	// Page contains Node contains URLPath which has Section
-	return p.Section(), nil
+	return p.s.PathSpec.MakeSegment(p.Section()), nil
 }
 
 func pageToPermalinkSections(p *Page, _ string) (string, error) {
 	// TODO(bep) we have some superflous URLize in this file, but let's
 	// deal with that later.
-	return path.Join(p.CurrentSection().sections...), nil
+
+	cs := p.CurrentSection()
+	if cs == nil {
+		return "", errors.New("\":sections\" attribute requires parent page but is nil")
+	}
+
+	sections := make([]string, len(cs.sections))
+	for i := range cs.sections {
+		sections[i] = p.s.PathSpec.MakeSegment(cs.sections[i])
+	}
+	return path.Join(sections...), nil
 }
 
 func init() {

hugolib/permalinks_test.go

@@ -19,36 +19,26 @@ import (
 )
 
 // testdataPermalinks is used by a couple of tests; the expandsTo content is
-// subject to the data in SIMPLE_PAGE_JSON.
+// subject to the data in simplePageJSON.
 var testdataPermalinks = []struct {
 	spec      string
 	valid     bool
 	expandsTo string
 }{
-	//{"/:year/:month/:title/", true, "/2012/04/spf13-vim-3.0-release-and-new-website/"},
-	//{"/:title", true, "/spf13-vim-3.0-release-and-new-website"},
-	//{":title", true, "spf13-vim-3.0-release-and-new-website"},
-	//{"/blog/:year/:yearday/:title", true, "/blog/2012/97/spf13-vim-3.0-release-and-new-website"},
+	{":title", true, "spf13-vim-3.0-release-and-new-website"},
 	{"/:year-:month-:title", true, "/2012-04-spf13-vim-3.0-release-and-new-website"},
-	{"/blog/:year-:month-:title", true, "/blog/2012-04-spf13-vim-3.0-release-and-new-website"},
-	{"/blog-:year-:month-:title", true, "/blog-2012-04-spf13-vim-3.0-release-and-new-website"},
-	//{"/blog/:fred", false, ""},
-	//{"/:year//:title", false, ""},
-	//{
-	//"/:section/:year/:month/:day/:weekdayname/:yearday/:title",
-	//true,
-	//"/blue/2012/04/06/Friday/97/spf13-vim-3.0-release-and-new-website",
-	//},
-	//{
-	//"/:weekday/:weekdayname/:month/:monthname",
-	//true,
-	//"/5/Friday/04/April",
-	//},
-	//{
-	//"/:slug/:title",
-	//true,
-	//"/spf13-vim-3-0-release-and-new-website/spf13-vim-3.0-release-and-new-website",
-	//},
+
+	{"/:year/:yearday/:month/:monthname/:day/:weekday/:weekdayname/", true, "/2012/97/04/April/06/5/Friday/"}, // Dates
+	{"/:section/", true, "/blue/"},                                // Section
+	{"/:title/", true, "/spf13-vim-3.0-release-and-new-website/"}, // Title
+	{"/:slug/", true, "/spf13-vim-3-0-release-and-new-website/"},  // Slug
+	{"/:filename/", true, "/test-page/"},                          // Filename
+	// TODO(moorereason): need test scaffolding for this.
+	//{"/:sections/", false, "/blue/"},                              // Sections
+
+	// Failures
+	{"/blog/:fred", false, ""},
+	{"/:year//:title", false, ""},
 }
 
 func TestPermalinkValidation(t *testing.T) {
@@ -75,7 +65,7 @@ func TestPermalinkExpansion(t *testing.T) {
 	page, err := s.NewPageFrom(strings.NewReader(simplePageJSON), "blue/test-page.md")
 
 	if err != nil {
-		t.Fatalf("failed before we began, could not parse SIMPLE_PAGE_JSON: %s", err)
+		t.Fatalf("failed before we began, could not parse simplePageJSON: %s", err)
 	}
 	for _, item := range testdataPermalinks {
 		if !item.valid {

hugolib/taxonomy_test.go

@@ -79,9 +79,11 @@ category = "categories"
 other = "others"
 empty = "empties"
 permalinked = "permalinkeds"
+subcats = "subcats"
 
 [permalinks]
 permalinkeds = "/perma/:slug/"
+subcats = "/subcats/:slug/"
 `
 
 	pageTemplate := `---
@@ -94,6 +96,8 @@ others:
 %s
 permalinkeds:
 %s
+subcats:
+%s
 ---
 # Doc
 `
@@ -105,10 +109,11 @@ permalinkeds:
 
 	fs := th.Fs
 
-	writeSource(t, fs, "content/p1.md", fmt.Sprintf(pageTemplate, "t1/c1", "- Tag1", "- cat1\n- \"cAt/dOg\"", "- o1", "- pl1"))
-	writeSource(t, fs, "content/p2.md", fmt.Sprintf(pageTemplate, "t2/c1", "- tag2", "- cat1", "- o1", "- pl1"))
-	writeSource(t, fs, "content/p3.md", fmt.Sprintf(pageTemplate, "t2/c12", "- tag2", "- cat2", "- o1", "- pl1"))
-	writeSource(t, fs, "content/p4.md", fmt.Sprintf(pageTemplate, "Hello World", "", "", "- \"Hello Hugo world\"", "- pl1"))
+	writeSource(t, fs, "content/p1.md", fmt.Sprintf(pageTemplate, "t1/c1", "- Tag1", "- cat1\n- \"cAt/dOg\"", "- o1", "- pl1", ""))
+	writeSource(t, fs, "content/p2.md", fmt.Sprintf(pageTemplate, "t2/c1", "- tag2", "- cat1", "- o1", "- pl1", ""))
+	writeSource(t, fs, "content/p3.md", fmt.Sprintf(pageTemplate, "t2/c12", "- tag2", "- cat2", "- o1", "- pl1", ""))
+	writeSource(t, fs, "content/p4.md", fmt.Sprintf(pageTemplate, "Hello World", "", "", "- \"Hello Hugo world\"", "- pl1", ""))
+	writeSource(t, fs, "content/p5.md", fmt.Sprintf(pageTemplate, "Sub/categories", "", "", "", "", "- \"sc0/sp1\""))
 
 	writeNewContentFile(t, fs.Source, "Category Terms", "2017-01-01", "content/categories/_index.md", 10)
 	writeNewContentFile(t, fs.Source, "Tag1 List", "2017-01-01", "content/tags/Tag1/_index.md", 10)
@@ -175,6 +180,7 @@ permalinkeds:
 		"others":       2,
 		"empties":      0,
 		"permalinkeds": 1,
+		"subcats":      1,
 	}
 
 	for taxonomy, count := range taxonomyTermPageCounts {
@@ -217,6 +223,11 @@ permalinkeds:
 	require.NotNil(t, permalinkeds)
 	require.Equal(t, fixURL("/blog/permalinkeds/"), permalinkeds.RelPermalink())
 
+	// Issue #5223
+	sp1 := s.getPage(KindTaxonomy, "subcats", "sc0/sp1")
+	require.NotNil(t, sp1)
+	require.Equal(t, fixURL("/blog/subcats/sc0/sp1/"), sp1.RelPermalink())
+
 	// Issue #3070 preserveTaxonomyNames
 	if preserveTaxonomyNames {
 		helloWorld := s.getPage(KindTaxonomy, "others", "Hello Hugo world")