feat: add wcwidth package

This package implements an interface on top of golang.org/x/text/width
to calculate the width of runes and strings similar to `wcwidth` and
`wcswidth` methods. It's a drop-in replacement to go-runewidth without
multi-rune emojis support i.e. ZWJ (zero-width joiner) is ignored.

go.work

@@ -20,6 +20,7 @@ use (
 	./sshkey
 	./term
 	./termios
+	./wcwidth
 	./windows
 	./xpty
 )

go.work.sum

@@ -1,53 +1,16 @@
-github.com/acarl005/stripansi v0.0.0-20180116102854-5a71ef0e047d/go.mod h1:asat636LX7Bqt5lYEZ27JNDcqxfjdBQuJ/MM4CN/Lzo=
-github.com/anmitsu/go-shlex v0.0.0-20200514113438-38f4b401e2be/go.mod h1:ySMOLuWl6zY27l47sB3qLNK6tF2fkHG55UZxx8oIVo4=
-github.com/charmbracelet/bubbletea v0.26.1 h1:xujcQeF73rh4jwu3+zhfQsvV18x+7zIjlw7/CYbzGJ0=
-github.com/charmbracelet/bubbletea v0.26.1/go.mod h1:FzKr7sKoO8iFVcdIBM9J0sJOcQv5nDQaYwsee3kpbgo=
-github.com/charmbracelet/bubbletea v0.26.5/go.mod h1:dz8CWPlfCCGLFbBlTY4N7bjLiyOGDJEnd2Muu7pOWhk=
+github.com/MakeNowJust/heredoc v1.0.0/go.mod h1:mG5amYoWBHf8vpLOuehzbGGw0EHxpZZ6lCpQ4fNJ8LE=
 github.com/charmbracelet/harmonica v0.2.0/go.mod h1:KSri/1RMQOZLbw7AHqgcBycp8pgJnQMYYT8QZRqZ1Ao=
-github.com/charmbracelet/lipgloss v0.11.0/go.mod h1:1UdRTH9gYgpcdNN5oBtjbu/IzNKtzVtb7sqN1t9LNn8=
-github.com/charmbracelet/lipgloss v0.12.0/go.mod h1:beLlcmkF7MWA+5UrKKIRo/VJ21xGXr7YJ9miWfdMRIU=
-github.com/charmbracelet/ssh v0.0.0-20240515141028-546b2ee33a4d/go.mod h1:8/Ve8iGRRIGFM1kepYfRF2pEOF5Y3TEZYoJaA54228U=
-github.com/charmbracelet/x/errors v0.0.0-20240117030013-d31dba354651/go.mod h1:2P0UgXMEa6TsToMSuFqKFQR+fZTO9CNGUNokkPatT/0=
-github.com/charmbracelet/x/exp/term v0.0.0-20240524151031-ff83003bf67a/go.mod h1:YBotIGhfoWhHDlnUpJMkjebGV2pdGRCn1Y4/Nk/vVcU=
-github.com/containerd/console v1.0.4-0.20230313162750-1ae8d489ac81/go.mod h1:YynlIjWYF8myEu6sdkwKIvGQq+cOckRm6So2avqoYAk=
-github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
+github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-runewidth v0.0.15/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
-github.com/muesli/reflow v0.3.0/go.mod h1:pbwTDkVPibjO2kyvBQRBxTWEEGDGq0FlB1BIKtnHY/8=
-github.com/sahilm/fuzzy v0.1.1-0.20230530133925-c48e322e2a8f/go.mod h1:VFvziUEIMCrT6A6tw2RFIXPXXmzXbOsSHF0DOI8ZK9Y=
-github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
+github.com/rivo/uniseg v0.4.4/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
+github.com/sahilm/fuzzy v0.1.1/go.mod h1:VFvziUEIMCrT6A6tw2RFIXPXXmzXbOsSHF0DOI8ZK9Y=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-golang.org/x/crypto v0.18.0/go.mod h1:R0j02AL6hcrfOiy9T4ZYp/rcWeMxM3L6QYxlOuEG1mg=
-golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561/go.mod h1:cyybsKvd6eL0RnXn6p/Grxp8F5bW7iYuBgsNCOHpMYE=
-golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8 h1:yixxcjnhBmY0nkL253HFVIm0JsFHwrHdT3Yh6szTnfY=
-golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8/go.mod h1:jj3sYF3dwk5D+ghuXyeI3r5MFf+NT2An6/9dOA95KSI=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
-golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
-golang.org/x/mod v0.13.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
-golang.org/x/mod v0.14.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
-golang.org/x/mod v0.18.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
-golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
-golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.19.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
-golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/telemetry v0.0.0-20240228155512-f48c80bd79b2/go.mod h1:TeRTkGYfJXctD9OcfyVLyj2J3IxLnKwHJR8f4D8a3YE=
-golang.org/x/term v0.16.0 h1:m+B6fahuftsE9qjo0VWp2FW0mB3MTJvR0BaMQrq0pmE=
-golang.org/x/term v0.16.0/go.mod h1:yn7UURbUtPyrVJPGPq404EukNFxcm/foM+bV/bfcDsY=
-golang.org/x/term v0.19.0/go.mod h1:2CuTdWZ7KHSQwUzKva0cbMg6q2DMI3Mmxp+gKJbskEk=
-golang.org/x/term v0.21.0/go.mod h1:ooXLefLobQVslOqselCNF4SxFAaoS6KujMbsGzSDmX0=
-golang.org/x/term v0.22.0/go.mod h1:F3qCibpT5AMpCRfhfT53vVJwhLtIVHhB9XDjfFvnMI4=
 golang.org/x/term v0.23.0/go.mod h1:DgV24QBUrK6jhZXl+20l6UWznPlwAHm1Q1mGHtydmSk=
 golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
-golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
-golang.org/x/tools v0.1.12 h1:VveCTK38A2rkS8ZqFY25HIDFscX5X9OoEhJd3quQmXU=
-golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
-golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
-golang.org/x/tools v0.14.0/go.mod h1:uYBEerGOWcJyEORxN+Ek8+TT266gXkNlHdJBwexUsBg=
 golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d/go.mod h1:aiJjzUbINMkxbQROHiO6hDPo2LHcIPhhQsa9DLh0yGk=
-golang.org/x/tools v0.22.0/go.mod h1:aCwcsjqvq7Yqt6TNyX7QMU2enbQ/Gt0bo6krSeEri+c=

wcwidth/go.mod

@@ -0,0 +1,5 @@
+module github.com/charmbracelet/x/wcwidth
+
+go 1.18
+
+require golang.org/x/text v0.17.0

wcwidth/go.sum

@@ -0,0 +1,2 @@
+golang.org/x/text v0.17.0 h1:XtiM5bkSOt+ewxlOE/aE/AKEHibwj/6gvWMl9Rsh0Qc=
+golang.org/x/text v0.17.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=

wcwidth/wcwidth.go

@@ -0,0 +1,45 @@
+// wcwidth is a Go implementation of wcwidth(3) that uses
+// golang.org/x/text/width. It is a drop-in replacement for
+// github.com/mattn/go-runewidth.
+//
+// Unlike go-runewidth, wcwidth treats East Asian ambiguous characters as
+// single-width characters. This is consistent with the behavior of wcwidth(3).
+
+package wcwidth
+
+import (
+	"unicode"
+
+	"golang.org/x/text/width"
+)
+
+// IsComb returns true if r is a Unicode combining character. Alias of:
+//
+//	unicode.Is(unicode.Mn, r)
+func IsComb(r rune) bool { return unicode.Is(unicode.Mn, r) }
+
+// RuneWidth returns fixed-width width of rune.
+// https://en.wikipedia.org/wiki/Halfwidth_and_fullwidth_forms#In_Unicode
+func RuneWidth(r rune) int {
+	if r == 0 || !unicode.IsPrint(r) || IsComb(r) {
+		return 0
+	}
+	k := width.LookupRune(r)
+	switch k.Kind() {
+	case width.EastAsianWide, width.EastAsianFullwidth:
+		return 2
+	case width.EastAsianNarrow, width.EastAsianHalfwidth, width.EastAsianAmbiguous, width.Neutral:
+		return 1
+	default:
+		return 0
+	}
+}
+
+// StringWidth returns fixed-width width of string.
+// https://en.wikipedia.org/wiki/Halfwidth_and_fullwidth_forms#In_Unicode
+func StringWidth(s string) (n int) {
+	for _, r := range s {
+		n += RuneWidth(r)
+	}
+	return n
+}

wcwidth/wcwidth_test.go

@@ -0,0 +1,105 @@
+package wcwidth
+
+import (
+	"testing"
+)
+
+// test cases copied from https://github.com/mattn/go-runewidth/raw/master/runewidth_test.go
+
+var stringwidthtests = []struct {
+	in    string
+	out   int
+	eaout int
+}{
+	{"■㈱の世界①", 10, 12},
+	{"スター☆", 7, 8},
+	{"つのだ☆HIRO", 11, 12},
+}
+
+func BenchmarkStringWidth(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		StringWidth(stringwidthtests[i%len(stringwidthtests)].in)
+	}
+}
+
+func TestStringWidth(t *testing.T) {
+	for _, tt := range stringwidthtests {
+		if out := StringWidth(tt.in); out != tt.out {
+			t.Errorf("StringWidth(%q) = %d, want %d", tt.in, out, tt.out)
+		}
+	}
+}
+
+var runewidthtests = []struct {
+	in     rune
+	out    int
+	eaout  int
+	nseout int
+}{
+	{'世', 2, 2, 2},
+	{'界', 2, 2, 2},
+	{'ｾ', 1, 1, 1},
+	{'ｶ', 1, 1, 1},
+	{'ｲ', 1, 1, 1},
+	{'☆', 1, 2, 2}, // double width in ambiguous
+	{'☺', 1, 1, 2},
+	{'☻', 1, 1, 2},
+	{'♥', 1, 2, 2},
+	{'♦', 1, 1, 2},
+	{'♣', 1, 2, 2},
+	{'♠', 1, 2, 2},
+	{'♂', 1, 2, 2},
+	{'♀', 1, 2, 2},
+	{'♪', 1, 2, 2},
+	{'♫', 1, 1, 2},
+	{'☼', 1, 1, 2},
+	{'↕', 1, 2, 2},
+	{'‼', 1, 1, 2},
+	{'↔', 1, 2, 2},
+	{'\x00', 0, 0, 0},
+	{'\x01', 0, 0, 0},
+	{'\u0300', 0, 0, 0},
+	{'\u2028', 0, 0, 0},
+	{'\u2029', 0, 0, 0},
+	{'a', 1, 1, 1}, // ASCII classified as "na" (narrow)
+	{'⟦', 1, 1, 1}, // non-ASCII classified as "na" (narrow)
+	{'👁', 1, 1, 2},
+}
+
+func BenchmarkRuneWidth(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		RuneWidth(runewidthtests[i%len(runewidthtests)].in)
+	}
+}
+
+func TestRuneWidth(t *testing.T) {
+	for i, tt := range runewidthtests {
+		if out := RuneWidth(tt.in); out != tt.out {
+			t.Errorf("case %d: RuneWidth(%q) = %d, want %d", i, tt.in, out, tt.out)
+		}
+	}
+}
+
+func TestZeroWidthJoiner(t *testing.T) {
+	tests := []struct {
+		in   string
+		want int
+	}{
+		{"👩", 2},
+		{"👩\u200d", 2},
+		{"👩\u200d🍳", 4},
+		{"\u200d🍳", 2},
+		{"👨\u200d👨", 4},
+		{"👨\u200d👨\u200d👧", 6},
+		{"🏳️\u200d🌈", 3},
+		{"あ👩\u200d🍳い", 8},
+		{"あ\u200d🍳い", 6},
+		{"あ\u200dい", 4},
+	}
+
+	for _, tt := range tests {
+		if got := StringWidth(tt.in); got != tt.want {
+			t.Errorf("StringWidth(%q) = %d, want %d", tt.in, got, tt.want)
+		}
+	}
+}