media: Make Type comparable

So we can use it and output.Format as map key etc.

This commit also fixes the media.Type implementation so it does not need to mutate itself to handle different suffixes for the same MIME type, e.g. jpg vs. jpeg.

This means that there are no Suffix or FullSuffix on media.Type anymore.

Fixes #8317
Fixes #8324

5 files changed, 45 insertions, 46 deletions

diff --git a/output/docshelper.go b/output/docshelper.go
index 42b871ab5..95e521ea3 100644
--- a/output/docshelper.go
+++ b/output/docshelper.go
@@ -76,7 +76,7 @@ func createLayoutExamples() interface{} {
 			Example:      example.name,
 			Kind:         example.d.Kind,
 			OutputFormat: example.f.Name,
-			Suffix:       example.f.MediaType.Suffix(),
+			Suffix:       example.f.MediaType.FirstSuffix.Suffix,
 			Layouts:      makeLayoutsPresentable(layouts),
 		})
 	}
diff --git a/output/layout.go b/output/layout.go
index 55e7fa305..91c7cc652 100644
--- a/output/layout.go
+++ b/output/layout.go
@@ -229,7 +229,7 @@ func (l *layoutBuilder) resolveVariations() []string {
 					continue
 				}
 
-				s := constructLayoutPath(typeVar, layoutVar, variation, l.f.MediaType.Suffix())
+				s := constructLayoutPath(typeVar, layoutVar, variation, l.f.MediaType.FirstSuffix.Suffix)
 				if s != "" {
 					layouts = append(layouts, s)
 				}
diff --git a/output/layout_test.go b/output/layout_test.go
index f98eea960..8b7a2b541 100644
--- a/output/layout_test.go
+++ b/output/layout_test.go
@@ -28,12 +28,8 @@ import (
 func TestLayout(t *testing.T) {
 	c := qt.New(t)
 
-	noExtNoDelimMediaType := media.TextType
-	noExtNoDelimMediaType.Suffixes = nil
-	noExtNoDelimMediaType.Delimiter = ""
-
-	noExtMediaType := media.TextType
-	noExtMediaType.Suffixes = nil
+	noExtNoDelimMediaType := media.WithDelimiterAndSuffixes(media.TextType, "", "")
+	noExtMediaType := media.WithDelimiterAndSuffixes(media.TextType, ".", "")
 
 	var (
 		ampType = Format{
diff --git a/output/outputFormat.go b/output/outputFormat.go
index ee5881e2a..1bd86d2ca 100644
--- a/output/outputFormat.go
+++ b/output/outputFormat.go
@@ -20,6 +20,8 @@ import (
 	"sort"
 	"strings"
 
+	"github.com/pkg/errors"
+
 	"github.com/mitchellh/mapstructure"
 
 	"github.com/gohugoio/hugo/media"
@@ -207,14 +209,16 @@ func (formats Formats) Less(i, j int) bool {
 // The lookup is case insensitive.
 func (formats Formats) GetBySuffix(suffix string) (f Format, found bool) {
 	for _, ff := range formats {
-		if strings.EqualFold(suffix, ff.MediaType.Suffix()) {
-			if found {
-				// ambiguous
-				found = false
-				return
+		for _, suffix2 := range ff.MediaType.Suffixes() {
+			if strings.EqualFold(suffix, suffix2) {
+				if found {
+					// ambiguous
+					found = false
+					return
+				}
+				f = ff
+				found = true
 			}
-			f = ff
-			found = true
 		}
 	}
 	return
@@ -310,6 +314,7 @@ func DecodeFormats(mediaTypes media.Types, maps ...map[string]interface{}) (Form
 				}
 
 				f = append(f, newOutFormat)
+
 			}
 		}
 	}
@@ -319,7 +324,7 @@ func DecodeFormats(mediaTypes media.Types, maps ...map[string]interface{}) (Form
 	return f, nil
 }
 
-func decode(mediaTypes media.Types, input, output interface{}) error {
+func decode(mediaTypes media.Types, input interface{}, output *Format) error {
 	config := &mapstructure.DecoderConfig{
 		Metadata:         nil,
 		Result:           output,
@@ -337,12 +342,19 @@ func decode(mediaTypes media.Types, input, output interface{}) error {
 						// If mediaType is a string, look it up and replace it
 						// in the map.
 						vv := dataVal.MapIndex(key)
-						if mediaTypeStr, ok := vv.Interface().(string); ok {
-							mediaType, found := mediaTypes.GetByType(mediaTypeStr)
+						vvi := vv.Interface()
+
+						switch vviv := vvi.(type) {
+						case media.Type:
+						// OK
+						case string:
+							mediaType, found := mediaTypes.GetByType(vviv)
 							if !found {
-								return c, fmt.Errorf("media type %q not found", mediaTypeStr)
+								return c, fmt.Errorf("media type %q not found", vviv)
 							}
 							dataVal.SetMapIndex(key, reflect.ValueOf(mediaType))
+						default:
+							return nil, errors.Errorf("invalid output format configuration; wrong type for media type, expected string (e.g. text/html), got %T", vvi)
 						}
 					}
 				}
@@ -357,12 +369,13 @@ func decode(mediaTypes media.Types, input, output interface{}) error {
 	}
 
 	return decoder.Decode(input)
+
 }
 
 // BaseFilename returns the base filename of f including an extension (ie.
 // "index.xml").
 func (f Format) BaseFilename() string {
-	return f.BaseName + f.MediaType.FullSuffix()
+	return f.BaseName + f.MediaType.FirstSuffix.FullSuffix
 }
 
 // MarshalJSON returns the JSON encoding of f.
diff --git a/output/outputFormat_test.go b/output/outputFormat_test.go
index d91f1e410..806998866 100644
--- a/output/outputFormat_test.go
+++ b/output/outputFormat_test.go
@@ -19,36 +19,26 @@ import (
 
 	qt "github.com/frankban/quicktest"
 	"github.com/gohugoio/hugo/media"
-	"github.com/google/go-cmp/cmp"
-)
-
-var eq = qt.CmpEquals(
-	cmp.Comparer(func(m1, m2 media.Type) bool {
-		return m1.Type() == m2.Type()
-	}),
-	cmp.Comparer(func(o1, o2 Format) bool {
-		return o1.Name == o2.Name
-	}),
 )
 
 func TestDefaultTypes(t *testing.T) {
 	c := qt.New(t)
 	c.Assert(CalendarFormat.Name, qt.Equals, "Calendar")
-	c.Assert(CalendarFormat.MediaType, eq, media.CalendarType)
+	c.Assert(CalendarFormat.MediaType, qt.Equals, media.CalendarType)
 	c.Assert(CalendarFormat.Protocol, qt.Equals, "webcal://")
 	c.Assert(CalendarFormat.Path, qt.HasLen, 0)
 	c.Assert(CalendarFormat.IsPlainText, qt.Equals, true)
 	c.Assert(CalendarFormat.IsHTML, qt.Equals, false)
 
 	c.Assert(CSSFormat.Name, qt.Equals, "CSS")
-	c.Assert(CSSFormat.MediaType, eq, media.CSSType)
+	c.Assert(CSSFormat.MediaType, qt.Equals, media.CSSType)
 	c.Assert(CSSFormat.Path, qt.HasLen, 0)
 	c.Assert(CSSFormat.Protocol, qt.HasLen, 0) // Will inherit the BaseURL protocol.
 	c.Assert(CSSFormat.IsPlainText, qt.Equals, true)
 	c.Assert(CSSFormat.IsHTML, qt.Equals, false)
 
 	c.Assert(CSVFormat.Name, qt.Equals, "CSV")
-	c.Assert(CSVFormat.MediaType, eq, media.CSVType)
+	c.Assert(CSVFormat.MediaType, qt.Equals, media.CSVType)
 	c.Assert(CSVFormat.Path, qt.HasLen, 0)
 	c.Assert(CSVFormat.Protocol, qt.HasLen, 0)
 	c.Assert(CSVFormat.IsPlainText, qt.Equals, true)
@@ -56,7 +46,7 @@ func TestDefaultTypes(t *testing.T) {
 	c.Assert(CSVFormat.Permalinkable, qt.Equals, false)
 
 	c.Assert(HTMLFormat.Name, qt.Equals, "HTML")
-	c.Assert(HTMLFormat.MediaType, eq, media.HTMLType)
+	c.Assert(HTMLFormat.MediaType, qt.Equals, media.HTMLType)
 	c.Assert(HTMLFormat.Path, qt.HasLen, 0)
 	c.Assert(HTMLFormat.Protocol, qt.HasLen, 0)
 	c.Assert(HTMLFormat.IsPlainText, qt.Equals, false)
@@ -64,7 +54,7 @@ func TestDefaultTypes(t *testing.T) {
 	c.Assert(AMPFormat.Permalinkable, qt.Equals, true)
 
 	c.Assert(AMPFormat.Name, qt.Equals, "AMP")
-	c.Assert(AMPFormat.MediaType, eq, media.HTMLType)
+	c.Assert(AMPFormat.MediaType, qt.Equals, media.HTMLType)
 	c.Assert(AMPFormat.Path, qt.Equals, "amp")
 	c.Assert(AMPFormat.Protocol, qt.HasLen, 0)
 	c.Assert(AMPFormat.IsPlainText, qt.Equals, false)
@@ -72,7 +62,7 @@ func TestDefaultTypes(t *testing.T) {
 	c.Assert(AMPFormat.Permalinkable, qt.Equals, true)
 
 	c.Assert(RSSFormat.Name, qt.Equals, "RSS")
-	c.Assert(RSSFormat.MediaType, eq, media.RSSType)
+	c.Assert(RSSFormat.MediaType, qt.Equals, media.RSSType)
 	c.Assert(RSSFormat.Path, qt.HasLen, 0)
 	c.Assert(RSSFormat.IsPlainText, qt.Equals, false)
 	c.Assert(RSSFormat.NoUgly, qt.Equals, true)
@@ -83,7 +73,7 @@ func TestGetFormatByName(t *testing.T) {
 	c := qt.New(t)
 	formats := Formats{AMPFormat, CalendarFormat}
 	tp, _ := formats.GetByName("AMp")
-	c.Assert(tp, eq, AMPFormat)
+	c.Assert(tp, qt.Equals, AMPFormat)
 	_, found := formats.GetByName("HTML")
 	c.Assert(found, qt.Equals, false)
 	_, found = formats.GetByName("FOO")
@@ -95,9 +85,9 @@ func TestGetFormatByExt(t *testing.T) {
 	formats1 := Formats{AMPFormat, CalendarFormat}
 	formats2 := Formats{AMPFormat, HTMLFormat, CalendarFormat}
 	tp, _ := formats1.GetBySuffix("html")
-	c.Assert(tp, eq, AMPFormat)
+	c.Assert(tp, qt.Equals, AMPFormat)
 	tp, _ = formats1.GetBySuffix("ics")
-	c.Assert(tp, eq, CalendarFormat)
+	c.Assert(tp, qt.Equals, CalendarFormat)
 	_, found := formats1.GetBySuffix("not")
 	c.Assert(found, qt.Equals, false)
 
@@ -129,18 +119,18 @@ func TestGetFormatByFilename(t *testing.T) {
 	formats := Formats{AMPFormat, HTMLFormat, noExtDelimFormat, noExt, CalendarFormat}
 	f, found := formats.FromFilename("my.amp.html")
 	c.Assert(found, qt.Equals, true)
-	c.Assert(f, eq, AMPFormat)
+	c.Assert(f, qt.Equals, AMPFormat)
 	_, found = formats.FromFilename("my.ics")
 	c.Assert(found, qt.Equals, true)
 	f, found = formats.FromFilename("my.html")
 	c.Assert(found, qt.Equals, true)
-	c.Assert(f, eq, HTMLFormat)
+	c.Assert(f, qt.Equals, HTMLFormat)
 	f, found = formats.FromFilename("my.nem")
 	c.Assert(found, qt.Equals, true)
-	c.Assert(f, eq, noExtDelimFormat)
+	c.Assert(f, qt.Equals, noExtDelimFormat)
 	f, found = formats.FromFilename("my.nex")
 	c.Assert(found, qt.Equals, true)
-	c.Assert(f, eq, noExt)
+	c.Assert(f, qt.Equals, noExt)
 	_, found = formats.FromFilename("my.css")
 	c.Assert(found, qt.Equals, false)
 }
@@ -172,7 +162,7 @@ func TestDecodeFormats(t *testing.T) {
 				c.Assert(len(f), qt.Equals, len(DefaultFormats), msg)
 				json, _ := f.GetByName("JSON")
 				c.Assert(json.BaseName, qt.Equals, "myindex")
-				c.Assert(json.MediaType, eq, media.JSONType)
+				c.Assert(json.MediaType, qt.Equals, media.JSONType)
 				c.Assert(json.IsPlainText, qt.Equals, false)
 			},
 		},
@@ -192,7 +182,7 @@ func TestDecodeFormats(t *testing.T) {
 				xml, found := f.GetByName("MYXMLFORMAT")
 				c.Assert(found, qt.Equals, true)
 				c.Assert(xml.BaseName, qt.Equals, "myxml")
-				c.Assert(xml.MediaType, eq, media.XMLType)
+				c.Assert(xml.MediaType, qt.Equals, media.XMLType)
 
 				// Verify that we haven't changed the DefaultFormats slice.
 				json, _ := f.GetByName("JSON")
@@ -234,7 +224,7 @@ func TestDecodeFormats(t *testing.T) {
 				xml, found := f.GetByName("MYOTHERXMLFORMAT")
 				c.Assert(found, qt.Equals, true)
 				c.Assert(xml.BaseName, qt.Equals, "myredefined")
-				c.Assert(xml.MediaType, eq, media.XMLType)
+				c.Assert(xml.MediaType, qt.Equals, media.XMLType)
 			},
 		},
 	}