v doc: implement color highlighting for the stdout format, enable it by default (#9312)

cmd/tools/vdoc/utils.v

@@ -2,6 +2,12 @@ module main
 
 import os
 import v.doc
+import term
+import v.table
+import v.scanner
+import v.token
+import strings
+import v.pref
 
 [inline]
 fn slug(title string) string {
@@ -130,3 +136,106 @@ fn gen_footer_text(d &doc.Doc, include_timestamp bool) string {
 	time_str := '$generated_time.day $generated_time.smonth() $generated_time.year $generated_time.hhmmss()'
 	return '$footer_text Generated on: $time_str'
 }
+
+fn color_highlight(code string, tb &table.Table) string {
+	builtin := ['bool', 'string', 'i8', 'i16', 'int', 'i64', 'i128', 'byte', 'u16', 'u32', 'u64',
+		'u128', 'rune', 'f32', 'f64', 'int_literal', 'float_literal', 'byteptr', 'voidptr', 'any']
+	highlight_code := fn (tok token.Token, typ HighlightTokenTyp) string {
+		lit := match typ {
+			.unone, .operator, .punctuation {
+				tok.kind.str()
+			}
+			.string {
+				term.yellow("'$tok.lit'")
+			}
+			.char {
+				term.yellow('`$tok.lit`')
+			}
+			.keyword {
+				term.blue(tok.lit)
+			}
+			.builtin, .symbol {
+				term.green(tok.lit)
+			}
+			.function {
+				term.cyan(tok.lit)
+			}
+			.number {
+				term.bright_blue(tok.lit)
+			}
+			else {
+				tok.lit
+			}
+		}
+		return lit
+	}
+	mut s := scanner.new_scanner(code, .parse_comments, &pref.Preferences{})
+	mut prev := token.Token{}
+	mut tok := s.scan()
+	mut next_tok := s.scan()
+	mut buf := strings.new_builder(200)
+	mut i := 0
+	for i < code.len {
+		if i == tok.pos {
+			mut tok_typ := HighlightTokenTyp.unone
+			match tok.kind {
+				.name {
+					if (tok.lit in builtin || tb.known_type(tok.lit))
+						&& (next_tok.kind != .lpar || prev.kind != .key_fn) {
+						tok_typ = .builtin
+					} else if next_tok.kind in [.lcbr, .rpar, .eof]
+						&& (next_tok.kind != .rpar || prev.kind in [.name, .amp]) {
+						tok_typ = .symbol
+					} else if next_tok.kind in [.lpar, .lt] {
+						tok_typ = .function
+					} else {
+						tok_typ = .name
+					}
+				}
+				.comment {
+					tok_typ = .comment
+				}
+				.chartoken {
+					tok_typ = .char
+				}
+				.string {
+					tok_typ = .string
+				}
+				.number {
+					tok_typ = .number
+				}
+				.key_true, .key_false {
+					tok_typ = .boolean
+				}
+				.lpar, .lcbr, .rpar, .rcbr, .lsbr, .rsbr, .semicolon, .colon, .comma, .dot {
+					tok_typ = .punctuation
+				}
+				else {
+					if token.is_key(tok.lit) || token.is_decl(tok.kind) {
+						tok_typ = .keyword
+					} else if tok.kind == .decl_assign || tok.kind.is_assign() || tok.is_unary()
+						|| tok.kind.is_relational() || tok.kind.is_infix() {
+						tok_typ = .operator
+					}
+				}
+			}
+			buf.write_string(highlight_code(tok, tok_typ))
+			if prev.kind != .eof {
+				prev = tok
+			} else {
+				break
+			}
+			if next_tok.kind != .eof {
+				i = tok.pos + tok.len
+				tok = next_tok
+				next_tok = s.scan()
+			} else {
+				break
+			}
+		} else {
+			buf.write_b(code[i])
+			i++
+		}
+	}
+	return buf.str()
+}

cmd/tools/vdoc/vdoc.v

@@ -11,6 +11,7 @@ import v.doc
 import v.pref
 import v.vmod
 import json
+import term
 
 const (
 	allowed_formats = ['md', 'markdown', 'json', 'text', 'stdout', 'html', 'htm']
@@ -44,6 +45,7 @@ struct Config {
 mut:
 	pub_only         bool = true
 	show_loc         bool // for plaintext
+	is_color         bool
 	is_multi         bool
 	is_vlib          bool
 	is_verbose       bool
@@ -86,7 +88,12 @@ fn (vd VDoc) gen_json(d doc.Doc) string {
 fn (vd VDoc) gen_plaintext(d doc.Doc) string {
 	cfg := vd.cfg
 	mut pw := strings.new_builder(200)
+	if cfg.is_color {
+		content_arr := d.head.content.split(' ')
+		pw.writeln('${term.blue(content_arr[0])} ${term.green(content_arr[1])}\n')
+	} else {
 		pw.writeln('$d.head.content\n')
+	}
 	comments := if cfg.include_examples {
 		d.head.merge_comments()
 	} else {
@@ -103,7 +110,11 @@ fn (vd VDoc) write_plaintext_content(contents []doc.DocNode, mut pw strings.Buil
 	cfg := vd.cfg
 	for cn in contents {
 		if cn.content.len > 0 {
+			if cfg.is_color {
+				pw.writeln(color_highlight(cn.content, vd.docs[0].table))
+			} else {
 				pw.writeln(cn.content)
+			}
 			if cn.comments.len > 0 && !cfg.pub_only {
 				comments := if cfg.include_examples {
 					cn.merge_comments()
@@ -369,6 +380,7 @@ fn (vd VDoc) vprintln(str string) {
 
 fn parse_arguments(args []string) Config {
 	mut cfg := Config{}
+	cfg.is_color = term.can_show_color_on_stdout()
 	for i := 0; i < args.len; i++ {
 		arg := args[i]
 		current_args := args[i..]
@@ -386,6 +398,12 @@ fn parse_arguments(args []string) Config {
 				cfg.output_type = set_output_type_from_str(format)
 				i++
 			}
+			'-color' {
+				cfg.is_color = true
+			}
+			'-no-color' {
+				cfg.is_color = false
+			}
 			'-inline-assets' {
 				cfg.inline_assets = true
 			}

cmd/v/help/doc.txt

@@ -4,6 +4,7 @@ Usage:
 Examples:
   v doc os
   v doc os File
+  v doc -no-color os
   v doc -o math.html math
   v doc -m -f html vlib/
 
@@ -20,6 +21,8 @@ Options:
   -o              Specifies the output file/folder path where to store the generated docs.
                   Set it to "stdout" to print the output instead of saving the contents
                   to a file.
+  -color          Force stdout colorize output.
+  -no-color       Force plain text output, without ANSI colors.
   -readme         Include README.md to docs if present.
   -v              Enables verbose logging. For debugging purposes.
   -no-timestamp   Omits the timestamp in the output file.