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-rw-r--r--vendor/github.com/rivo/uniseg/width.go61
1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/github.com/rivo/uniseg/width.go b/vendor/github.com/rivo/uniseg/width.go
new file mode 100644
index 000000000..975a9f134
--- /dev/null
+++ b/vendor/github.com/rivo/uniseg/width.go
@@ -0,0 +1,61 @@
+package uniseg
+
+// EastAsianAmbiguousWidth specifies the monospace width for East Asian
+// characters classified as Ambiguous. The default is 1 but some rare fonts
+// render them with a width of 2.
+var EastAsianAmbiguousWidth = 1
+
+// runeWidth returns the monospace width for the given rune. The provided
+// grapheme property is a value mapped by the [graphemeCodePoints] table.
+//
+// Every rune has a width of 1, except for runes with the following properties
+// (evaluated in this order):
+//
+// - Control, CR, LF, Extend, ZWJ: Width of 0
+// - \u2e3a, TWO-EM DASH: Width of 3
+// - \u2e3b, THREE-EM DASH: Width of 4
+// - East-Asian width Fullwidth and Wide: Width of 2 (Ambiguous and Neutral
+// have a width of 1)
+// - Regional Indicator: Width of 2
+// - Extended Pictographic: Width of 2, unless Emoji Presentation is "No".
+func runeWidth(r rune, graphemeProperty int) int {
+ switch graphemeProperty {
+ case prControl, prCR, prLF, prExtend, prZWJ:
+ return 0
+ case prRegionalIndicator:
+ return 2
+ case prExtendedPictographic:
+ if property(emojiPresentation, r) == prEmojiPresentation {
+ return 2
+ }
+ return 1
+ }
+
+ switch r {
+ case 0x2e3a:
+ return 3
+ case 0x2e3b:
+ return 4
+ }
+
+ switch propertyEastAsianWidth(r) {
+ case prW, prF:
+ return 2
+ case prA:
+ return EastAsianAmbiguousWidth
+ }
+
+ return 1
+}
+
+// StringWidth returns the monospace width for the given string, that is, the
+// number of same-size cells to be occupied by the string.
+func StringWidth(s string) (width int) {
+ state := -1
+ for len(s) > 0 {
+ var w int
+ _, s, w, state = FirstGraphemeClusterInString(s, state)
+ width += w
+ }
+ return
+}