Implement the trim_whitespace option

Needed for help text formatting

tools/utils/style/indent-and-wrap.go

@@ -263,12 +263,24 @@ func (self hyperlink_state) as_escape_codes(for_close bool) string {
 type line_builder struct {
 	buf                        []byte
 	cursor_pos                 int
+	seen_non_space_chars       bool
+	pos_of_trailing_whitespace int
 }
 
-func (self *line_builder) reset() string {
+func (self *line_builder) reset(trim_whitespace bool) string {
 	ans := string(self.buf)
+	if trim_whitespace && self.pos_of_trailing_whitespace > -1 {
+		prefix := ans[:self.pos_of_trailing_whitespace]
+		tp := strings.TrimRightFunc(prefix, is_space)
+		if len(tp) != len(prefix) {
+			ans = tp + ans[self.pos_of_trailing_whitespace:]
+		}
+
+	}
 	self.buf = self.buf[:0]
 	self.cursor_pos = 0
+	self.seen_non_space_chars = false
+	self.pos_of_trailing_whitespace = -1
 	return ans
 }
 
@@ -277,15 +289,34 @@ func (self *line_builder) has_space_for_width(w, max_width int) bool {
 }
 
 func (self *line_builder) add_char(ch rune) {
+	self.seen_non_space_chars = true
 	self.buf = utf8.AppendRune(self.buf, ch)
 	self.cursor_pos += wcswidth.Runewidth(ch)
+	self.pos_of_trailing_whitespace = -1
+}
+
+func (self *line_builder) add_space(ch rune, trim_whitespace bool) {
+	if !trim_whitespace || self.seen_non_space_chars {
+		self.buf = utf8.AppendRune(self.buf, ch)
+		self.pos_of_trailing_whitespace = len(self.buf)
+		self.cursor_pos += wcswidth.Runewidth(ch)
+	}
 }
 
 func (self *line_builder) add_word(word []byte, width int) {
+	self.seen_non_space_chars = true
+	self.pos_of_trailing_whitespace = -1
 	self.buf = append(self.buf, word...)
 	self.cursor_pos += width
 }
 
+func (self *line_builder) add_indent(word string, width int) {
+	if word != "" {
+		self.buf = append(self.buf, word...)
+		self.cursor_pos += width
+	}
+}
+
 func (self *line_builder) add_escape_code(code string) {
 	self.buf = append(self.buf, code...)
 }
@@ -360,6 +391,7 @@ type wrapper struct {
 	ep                  wcswidth.EscapeCodeParser
 	indent              string
 	width, indent_width int
+	trim_whitespace     bool
 
 	sgr                     sgr_state
 	hyperlink               hyperlink_state
@@ -372,7 +404,7 @@ type wrapper struct {
 func (self *wrapper) newline_prefix() {
 	self.current_line.add_escape_code(self.sgr.as_escape_codes(true))
 	self.current_line.add_escape_code(self.hyperlink.as_escape_codes(true))
-	self.current_line.add_word(utils.UnsafeStringToBytes(self.indent), self.indent_width)
+	self.current_line.add_indent(self.indent, self.indent_width)
 	self.current_line.add_escape_code(self.sgr.as_escape_codes(false))
 	self.current_line.add_escape_code(self.hyperlink.as_escape_codes(false))
 }
@@ -387,7 +419,7 @@ func (self *wrapper) append_line(line string) {
 }
 
 func (self *wrapper) end_current_line() {
-	line := self.current_line.reset()
+	line := self.current_line.reset(self.trim_whitespace)
 	if strings.HasSuffix(line, self.indent) && wcswidth.Stringwidth(line) == self.indent_width {
 		line = line[:len(line)-len(self.indent)]
 	}
@@ -413,16 +445,22 @@ func (self *wrapper) print_word() {
 	})
 }
 
+func is_space(ch rune) bool {
+	return ch != 0xa0 && unicode.IsSpace(ch)
+}
+
 func (self *wrapper) handle_rune(ch rune) error {
 	if ch == '\n' {
 		self.print_word()
 		self.end_current_line()
-	} else if self.current_word.has_text() && ch != 0xa0 && unicode.IsSpace(ch) {
+	} else if is_space(ch) {
+		if self.current_word.has_text() {
 			self.print_word()
+		}
 		if self.current_line.cursor_pos >= self.width {
 			self.end_current_line()
 		}
-		self.current_line.add_char(ch)
+		self.current_line.add_space(ch, self.trim_whitespace)
 	} else {
 		num_of_bytes_written := self.current_word.add_rune(ch)
 		if self.current_word.width() > self.width {
@@ -448,18 +486,18 @@ func (self *wrapper) wrap_text(text string) []string {
 	if text == "" {
 		return []string{""}
 	}
-	self.current_line.reset()
+	self.current_line.reset(self.trim_whitespace)
 	self.current_word.reset(func([]byte) {})
 	self.lines = self.lines[:0]
-	self.current_line.add_word(utils.UnsafeStringToBytes(self.indent), self.indent_width)
+	self.current_line.add_indent(self.indent, self.indent_width)
 	self.ep.ParseString(text)
 	if !self.current_word.is_empty() {
 		self.print_word()
 	}
 	self.end_current_line()
-	last_line := self.current_line.reset()
+	last_line := self.current_line.reset(self.trim_whitespace)
 	self.newline_prefix()
-	if last_line == self.current_line.reset() {
+	if last_line == self.current_line.reset(self.trim_whitespace) {
 		last_line = ""
 	}
 	if last_line != "" {
@@ -470,7 +508,7 @@ func (self *wrapper) wrap_text(text string) []string {
 
 func new_wrapper(opts WrapOptions, width int) *wrapper {
 	width = utils.Max(2, width)
-	ans := wrapper{indent: opts.Indent, width: width, indent_width: wcswidth.Stringwidth(opts.Indent)}
+	ans := wrapper{indent: opts.Indent, width: width, trim_whitespace: opts.Trim_whitespace, indent_width: wcswidth.Stringwidth(opts.Indent)}
 	if opts.Ignore_lines_containing != "" {
 		ans.ignore_lines_containing = utils.Splitlines(opts.Ignore_lines_containing)
 	}
@@ -485,8 +523,8 @@ func new_wrapper(opts WrapOptions, width int) *wrapper {
 
 type WrapOptions struct {
 	Ignore_lines_containing string
-	Trim_whitespace         bool // trim whitespace at the start and end of lines (start is after indent)
+	Trim_whitespace         bool   // trim whitespace at the start and end of lines (start is after indent).
-	Indent                  string
+	Indent                  string // indent to add at the start of every line all formatting is cleared for the indent.
 }
 
 func WrapTextAsLines(text string, width int, opts WrapOptions) []string {

tools/utils/style/indent-and-wrap_test.go

@@ -3,6 +3,7 @@
 package style
 
 import (
+	"encoding/json"
 	"strings"
 	"testing"
 )
@@ -16,7 +17,8 @@ func TestFormatWithIndent(t *testing.T) {
 		q := opts.Indent + strings.Join(expected, "")
 		actual := WrapText(text, screen_width, opts)
 		if actual != q {
-			t.Fatalf("\nFailed for: %#v\nexpected: %#v\nactual:   %#v", text, q, actual)
+			os, _ := json.Marshal(opts)
+			t.Fatalf("\nFailed for: %#v\nOptions: %s\nexpected: %#v\nactual:   %#v", text, os, q, actual)
 		}
 	}
 
@@ -27,6 +29,16 @@ func TestFormatWithIndent(t *testing.T) {
 	screen_width = 3
 	tx("one tw", "one\n tw")
 
+	screen_width = 4
+	opts.Trim_whitespace = true
+	opts.Indent = "X"
+	tx("one two", "one\nXtwo")
+	tx("\x1b[2mone \x1b[mtwo", "\x1b[2mone\n\x1b[222mX\x1b[2m\x1b[mtwo")
+	screen_width = 3
+	tx("on tw", "on\nXtw")
+	opts.Indent = ""
+	opts.Trim_whitespace = false
+
 	opts.Indent = "__"
 	screen_width = 11
 	tx("testing\n\ntwo", "testing\n\n__two")