ReverseCodeMap, map unicode character to lists of short codes

emoji.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"regexp"
+	"sort"
 	"unicode"
 )
 
@@ -22,6 +23,48 @@ func CodeMap() map[string]string {
 	return emojiCodeMap
 }
 
+// emojiRevCodeMap maps unicode characters to lists of short codes.
+var emojiRevCodeMap = make(map[string][]string, len(emojiCodeMap))
+
+func init() {
+	for shortCode, unicode := range emojiCodeMap {
+		emojiRevCodeMap[unicode] = append(emojiRevCodeMap[unicode], shortCode)
+	}
+	// ensure deterministic ordering for aliases
+	for _, value := range emojiRevCodeMap {
+		sort.Slice(value, func(i, j int) bool {
+			if len(value[i]) == len(value[j]) {
+				return value[i] < value[j]
+			}
+			return len(value[i]) < len(value[j])
+		})
+	}
+}
+
+// RevCodeMap gets the underlying map of emoji.
+func RevCodeMap() map[string][]string {
+	return emojiRevCodeMap
+}
+
+func AliasList(shortCode string) []string {
+	return emojiRevCodeMap[emojiCodeMap[shortCode]]
+}
+
+// HasAlias flags if the given `shortCode` has multiple aliases with other
+// codes.
+func HasAlias(shortCode string) bool {
+	return len(AliasList(shortCode)) > 1
+}
+
+// NormalizeShortCode normalizes a given `shortCode` to a deterministic alias.
+func NormalizeShortCode(shortCode string) string {
+	shortLists := AliasList(shortCode)
+	if len(shortLists) == 0 {
+		return shortCode
+	}
+	return shortLists[0]
+}
+
 // regular expression that matches :flag-[countrycode]:
 var flagRegexp = regexp.MustCompile(":flag-([a-z]{2}):")
 
@@ -99,7 +142,7 @@ func Println(a ...interface{}) (int, error) {
 
 // Printf is fmt.Printf which supports emoji
 func Printf(format string, a ...interface{}) (int, error) {
-	return fmt.Printf(compile(fmt.Sprintf(format, a...)))
+	return fmt.Print(compile(fmt.Sprintf(format, a...)))
 }
 
 // Fprint is fmt.Fprint which supports emoji

emoji_test.go

@@ -59,6 +59,38 @@ func TestCodeMap(t *testing.T) {
 	}
 }
 
+func TestRevCodeMap(t *testing.T) {
+	m := RevCodeMap()
+	if &emojiRevCodeMap == &m {
+		t.Error("emojiRevCodeMap != EmojiRevCodeMap")
+	}
+}
+
+func TestHasAlias(t *testing.T) {
+	hasAlias := HasAlias(":+1:")
+	if !hasAlias {
+		t.Error(":+1: doesn't have an alias")
+	}
+	hasAlias = HasAlias(":no-good:")
+	if hasAlias {
+		t.Error(":no-good: has an alias")
+	}
+}
+
+func TestNoramlizeShortCode(t *testing.T) {
+	test := ":thumbs_up:"
+	expected := ":+1:"
+	normalized := NormalizeShortCode(test)
+	if normalized != expected {
+		t.Errorf("Normalized %q != %q", test, expected)
+	}
+	test = ":no-good:"
+	normalized = NormalizeShortCode(test)
+	if normalized != test {
+		t.Errorf("Normalized %q != %q", test, normalized)
+	}
+}
+
 func TestPrint(t *testing.T) {
 	_, err := Print(beerKey, beerText)
 	if err != nil {
@@ -154,7 +186,7 @@ func BenchmarkFprint(b *testing.B) {
 		defer putBuffer(buff)
 		Fprint(buff, string(in))
 
-		bc := make([]byte, buff.Len(), buff.Len())
+		bc := make([]byte, buff.Len())
 		copy(bc, buff.Bytes())
 		return bc
 	}