gno.land/p/moul/x/daily/humanize/v0⧉

1// Package humanize formats numbers for people rather than machines, as a pure,2// reusable package: byte sizes, thousands separators, ordinals, pluralisation3// and block-height "durations".4//5// Everything is integer-only. There are no floats here on purpose: gno has no6// float determinism guarantees worth relying on for consensus output, and a7// rendered value that differs between nodes would be a consensus bug. One8// decimal place is produced by scaling by 10 and taking a remainder.9//10// Durations are expressed in BLOCKS, not seconds. There is no wall clock on11// chain, so "about 2 hours" is a lie dressed as precision; this package says12// "~1200 blocks" and lets the caller decide what that means on their chain.13//14// A live demo of this package is at15// [r/moul/x/daily/humanizedemo](/r/moul/x/daily/humanizedemo/v0).16package humanize1718import (19	"strconv"20	"strings"21)2223// Bytes renders n bytes with SI-ish binary units and one decimal place.24// Negative input is rendered with a leading minus rather than rejected.25func Bytes(n int64) string {26	neg := n < 027	if neg {28		n = -n29	}30	const unit = 102431	if n < unit {32		s := strconv.FormatInt(n, 10) + " B"33		if neg {34			return "-" + s35		}36		return s37	}38	units := []string{"KiB", "MiB", "GiB", "TiB", "PiB", "EiB"}39	div := int64(unit)40	i := 041	for n/div >= unit && i < len(units)-1 {42		div *= unit43		i++44	}45	// one decimal place without floats: scale by 10, then split46	scaled := n * 10 / div47	whole, freq := scaled/10, scaled%1048	s := strconv.FormatInt(whole, 10)49	if freq != 0 {50		s += "." + strconv.FormatInt(freq, 10)51	}52	s += " " + units[i]53	if neg {54		return "-" + s55	}56	return s57}5859// Comma inserts thousands separators: 1234567 -> "1,234,567".60func Comma(n int64) string {61	neg := n < 062	if neg {63		n = -n64	}65	s := strconv.FormatInt(n, 10)66	var b strings.Builder67	for i, c := range []byte(s) {68		if i > 0 && (len(s)-i)%3 == 0 {69			b.WriteByte(',')70		}71		b.WriteByte(c)72	}73	if neg {74		return "-" + b.String()75	}76	return b.String()77}7879// Ordinal renders 1 -> "1st", 2 -> "2nd", 11 -> "11th".80//81// The teens are the trap: 11/12/13 take "th" despite ending in 1/2/3, so the82// 11–13 case must be checked before the last digit.83func Ordinal(n int64) string {84	s := strconv.FormatInt(n, 10)85	a := n86	if a < 0 {87		a = -a88	}89	if a%100 >= 11 && a%100 <= 13 {90		return s + "th"91	}92	switch a % 10 {93	case 1:94		return s + "st"95	case 2:96		return s + "nd"97	case 3:98		return s + "rd"99	}100	return s + "th"101}102103// Plural returns "1 block" / "2 blocks", using plural when given, else word+"s".104func Plural(n int64, word, plural string) string {105	if n == 1 || n == -1 {106		return strconv.FormatInt(n, 10) + " " + word107	}108	if plural == "" {109		plural = word + "s"110	}111	return strconv.FormatInt(n, 10) + " " + plural112}113114// Blocks renders a block count at a coarse magnitude — deliberately vague,115// because a block count is not a wall-clock duration.116func Blocks(n int64) string {117	switch {118	case n < 0:119		return "in the past"120	case n == 0:121		return "now"122	case n < 10:123		return Plural(n, "block", "")124	case n < 1000:125		return "~" + Comma(n/10*10) + " blocks"126	default:127		return "~" + Comma(n/100*100) + " blocks"128	}129}130131// Truncate shortens s to at most max runes, appending "…" when it cut.132// Counts RUNES, not bytes, so a multi-byte string is not sliced mid-character.133func Truncate(s string, max int) string {134	if max <= 0 {135		return ""136	}137	r := []rune(s)138	if len(r) <= max {139		return s140	}141	if max == 1 {142		return "…"143	}144	return string(r[:max-1]) + "…"145}146