v1.13.0

ADDED:
* stringsx functions

stringsx/consts.go

@@ -4,8 +4,3 @@ const (
 	// DefMaskStr is the string used as the default maskStr if left empty in [Redact].
 	DefMaskStr string = "***"
 )
-
-const (
-	// DefIndentStr is the string used as the default indent if left empty in [Indent].
-	DefIndentStr string = "\t"
-)

stringsx/doc.go

@@ -1,4 +1,17 @@
 /*
 Package stringsx aims to extend functionality of the stdlib [strings] module.
+
+Note that if you need a way of mimicking Bash's shell quoting rules, [desertbit/shlex] or [buildkite/shellwords]
+would be better options than [google/shlex] but this package does not attempt to reproduce
+any of that functionality.
+
+For line splitting, one should use [muesli/reflow/wordwrap].
+Likewise for indentation, one should use [muesli/reflow/indent].
+
+[desertbit/shlex]: https://pkg.go.dev/github.com/desertbit/go-shlex
+[buildkite/shellwords]: https://pkg.go.dev/github.com/buildkite/shellwords
+[google/shlex]: https://pkg.go.dev/github.com/google/shlex
+[muesli/reflow/wordwrap]: https://pkg.go.dev/github.com/muesli/reflow/wordwrap
+[muesli/reflow/indent]: https://pkg.go.dev/github.com/muesli/reflow/indent
 */
 package stringsx

stringsx/funcs.go

@@ -1,96 +1,170 @@
 package stringsx
 
 import (
+	`fmt`
 	`strings`
 	`unicode`
 )
 
 /*
-Indent takes string s and indents it with string `indent` `level` times.
+LenSplit formats string `s` to break at, at most, every `width` characters.
 
-If indent is an empty string, [DefIndentStr] will be used.
+Any existing newlines (e.g. \r\n) will be removed during a string/
+substring/line's length calculation. (e.g. `foobarbaz\n` and `foobarbaz\r\n` are
+both considered to be lines of length 9, not 10 and 11 respectively).
 
-If ws is true, lines consisting of only whitespace will be indented as well.
+This also means that any newlines (\n or \r\n) are inherently removed from
-(To then trim any extraneous trailing space, you may want to use [TrimSpaceRight]
+`out` (even if included in `wordWrap`; see below).
-or [TrimLines].)
 
-If empty is true, lines with no content will be replaced with lines that purely
+Note that if `s` is multiline (already contains newlines), they will be respected
-consist of (indent * level) (otherwise they will be left as empty lines).
+as-is - that is, if a line ends with less than `width` chars and then has a newline,
+it will be preserved as an empty element. That is to say:
 
-This function can also be used to prefix lines with arbitrary strings as well.
+	"foo\nbar\n\n" → []string{"foo", "bar", ""}
-e.g:
+	"foo\n\nbar\n" → []string{"foo", "", "bar"}
 
-	Indent("foo\nbar\nbaz\n", "# ", 1, false, false)
+This splitter is particularly simple. If you need wordwrapping, it should be done
-
+with e.g. [github.com/muesli/reflow/wordwrap].
-would yield:
-
-	# foo
-	# bar
-	# baz
-	<empty line>
-
-thus allowing you to "comment out" multiple lines at once.
 */
-func Indent(s, indent string, level uint, ws, empty bool) (indented string) {
+func LenSplit(s string, width uint) (out []string) {
 
-	var i string
+	var end int
-	var nl string
+	var line string
-	var endsNewline bool
+	var lineRunes []rune
-	var sb strings.Builder
-	var lineStripped string
 
-	if indent == "" {
+	if width == 0 {
-		indent = DefIndentStr
+		out = []string{s}
-	}
-
-	// This condition functionally won't do anything, so just return the input as-is.
-	if level == 0 {
-		indented = s
 		return
 	}
 
-	i = strings.Repeat(indent, int(level))
+	for line = range strings.Lines(s) {
+		line = strings.TrimRight(line, "\n")
+		line = strings.TrimRight(line, "\r")
 
-	// This condition functionally won't do anything, so just return the input as-is.
+		lineRunes = []rune(line)
-	if s == "" {
-		if empty {
-			indented = i
-		}
-		return
-	}
 
-	for line := range strings.Lines(s) {
+		if uint(len(lineRunes)) <= width {
-		lineStripped = strings.TrimSpace(line)
+			out = append(out, line)
-		nl = getNewLine(line)
-		endsNewline = nl != ""
-		// fmt.Printf("%#v => %#v\n", line, lineStripped)
-		if lineStripped == "" {
-			// fmt.Printf("WS/EMPTY LINE (%#v) (ws %v, empty %v): \n", s, ws, empty)
-			if line != (lineStripped + nl) {
-				// whitespace-only line
-				if ws {
-					sb.WriteString(i)
-				}
-			} else {
-				// empty line
-				if empty {
-					sb.WriteString(i)
-				}
-			}
-			sb.WriteString(line)
 			continue
 		}
-		// non-empty/non-whitespace-only line.
+
-		sb.WriteString(i + line)
+		for i := 0; i < len(lineRunes); i += int(width) {
+			end = i + int(width)
+			if end > len(lineRunes) {
+				end = len(lineRunes)
+			}
+			out = append(out, string(lineRunes[i:end]))
+		}
 	}
 
-	// If it ends with a trailing newline and nothing after, strings.Lines() will skip the last (empty) line.
+	return
-	if endsNewline && empty {
-		nl = getNewLine(s)
-		sb.WriteString(i)
 }
 
-	indented = sb.String()
+/*
+LenSplitStr wraps [LenSplit] but recombines into a new string with newlines.
+
+It's mostly just a convenience wrapper.
+
+All arguments remain the same as in [LenSplit] with an additional one,
+`winNewLine`, which if true will use \r\n as the newline instead of \n.
+*/
+func LenSplitStr(s string, width uint, winNewline bool) (out string) {
+
+	var outSl []string = LenSplit(s, width)
+
+	if winNewline {
+		out = strings.Join(outSl, "\r\n")
+	} else {
+		out = strings.Join(outSl, "\n")
+	}
+
+	return
+}
+
+/*
+Pad pads each element in `s` to length `width` using `pad`.
+If `pad` is empty, a single space (0x20) will be assumed.
+Note that `width` operates on rune size, not byte size.
+(In ASCII, they will be the same size.)
+
+If a line in `s` is greater than or equal to `width`,
+no padding will be performed.
+
+If `leftPad` is true, padding will be applied to the "left" (beginning")
+of each element instead of the "right" ("end").
+*/
+func Pad(s []string, width uint, pad string, leftPad bool) (out []string) {
+
+	var idx int
+	var padIdx int
+	var runeIdx int
+	var padLen uint
+	var elem string
+	var unpadLen uint
+	var tmpPadLen int
+	var padRunes []rune
+	var tmpPad []rune
+
+	if width == 0 {
+		out = s
+		return
+	}
+
+	out = make([]string, len(s))
+
+	// Easy; supported directly in fmt.
+	if pad == "" {
+		for idx, elem = range s {
+			if leftPad {
+				out[idx] = fmt.Sprintf("%*s", width, elem)
+			} else {
+				out[idx] = fmt.Sprintf("%-*s", width, elem)
+			}
+		}
+		return
+	}
+
+	// This gets a little more tricky.
+	padRunes = []rune(pad)
+	padLen = uint(len(padRunes))
+	for idx, elem = range s {
+		// First we need to know the number of runes in elem.
+		unpadLen = uint(len([]rune(elem)))
+		// If it's more than/equal to width, as-is.
+		if unpadLen >= width {
+			out[idx] = elem
+		} else {
+			// Otherwise, we need to construct/calculate a pad.
+			if (width-unpadLen)%padLen == 0 {
+				// Also easy enough.
+				if leftPad {
+					out[idx] = fmt.Sprintf("%s%s", strings.Repeat(pad, int((width-unpadLen)/padLen)), elem)
+				} else {
+					out[idx] = fmt.Sprintf("%s%s", elem, strings.Repeat(pad, int((width-unpadLen)/padLen)))
+				}
+			} else {
+				// This is where it gets a little hairy.
+				tmpPad = []rune{}
+				tmpPadLen = int(width - unpadLen)
+				idx = 0
+				padIdx = 0
+				for runeIdx = range tmpPadLen {
+					tmpPad[runeIdx] = padRunes[padIdx]
+					if uint(padIdx) >= padLen {
+						padIdx = 0
+					} else {
+						padIdx++
+					}
+					runeIdx++
+				}
+				if leftPad {
+					out[idx] = fmt.Sprintf("%s%s", string(tmpPad), elem)
+				} else {
+					out[idx] = fmt.Sprintf("%s%s", elem, string(tmpPad))
+				}
+			}
+		}
+	}
 
 	return
 }
@@ -118,6 +192,9 @@ As a safety precaution, if:
 	len(s) <= (leading + trailing)
 
 then the entire string will be *masked* and no unmasking will be performed.
+
+Note that this DOES NOT do a string *replace*, it provides a masked version of `s` itself.
+Wrap Redact with [strings.ReplaceAll] if you want to replace a certain value with a masked one.
 */
 func Redact(s, maskStr string, leading, trailing uint, newlines bool) (redacted string) {
 
@@ -218,7 +295,7 @@ func TrimLines(s string, left, right bool) (trimmed string) {
 	return
 }
 
-// TrimSpaceLeft is like [strings.TrimSpace] but only removes leading whitespace from string s.
+// TrimSpaceLeft is like [strings.TrimSpace] but only removes leading whitespace from string `s`.
 func TrimSpaceLeft(s string) (trimmed string) {
 
 	trimmed = strings.TrimLeftFunc(s, unicode.IsSpace)
@@ -236,7 +313,7 @@ func TrimSpaceRight(s string) (trimmed string) {
 	return
 }
 
-// getNewLine is too unpredictable to be used outside of this package so it isn't exported.
+// getNewLine is too unpredictable/nuanced to be used as part of a public API promise so it isn't exported.
 func getNewLine(s string) (nl string) {
 
 	if strings.HasSuffix(s, "\r\n") {