tools: implement progres bar for `v check-md .`

cmd/tools/vcheck-md.v

@@ -14,6 +14,7 @@ const (
 	too_long_line_length = 100
 	term_colors          = term.can_show_color_on_stderr()
 	hide_warnings        = '-hide-warnings' in os.args || '-w' in os.args
+	show_progress        = os.getenv('GITHUB_JOB') == '' && '-silent' !in os.args
 	non_option_args      = cmdline.only_non_options(os.args[2..])
 )
 
@@ -41,6 +42,10 @@ fn main() {
 		println('´-all´ flag is deprecated. Please use ´v check-md .´ instead.')
 		exit(1)
 	}
+	if show_progress {
+		// this is intended to be replaced by the progress lines
+		println('')
+	}
 	mut files_paths := non_option_args.clone()
 	mut res := CheckResult{}
 	if term_colors {
@@ -64,6 +69,9 @@ fn main() {
 		}
 		res += mdfile.check()
 	}
+	if res.errors == 0 && show_progress {
+		term.clear_previous_line()
+	}
 	if res.warnings > 0 || res.errors > 0 || res.oks > 0 {
 		println('\nWarnings: $res.warnings | Errors: $res.errors | OKs: $res.oks')
 	}
@@ -145,9 +153,17 @@ mut:
 	state    MDFileParserState = .markdown
 }
 
+fn (mut f MDFile) progress(message string) {
+	if show_progress {
+		term.clear_previous_line()
+		println('File: ${f.path:-30s}, Lines: ${f.lines.len:5}, $message')
+	}
+}
+
 fn (mut f MDFile) check() CheckResult {
 	mut res := CheckResult{}
 	for j, line in f.lines {
+		// f.progress('line: $j')
 		if line.len > too_long_line_length {
 			if f.state == .vexample {
 				wprintln(wline(f.path, j, line.len, 'long V example line'))
@@ -265,6 +281,7 @@ fn (mut f MDFile) check_examples() CheckResult {
 		mut acommands := e.command.split(' ')
 		nofmt := 'nofmt' in acommands
 		for command in acommands {
+			f.progress('example from $e.sline to $e.eline, command: $command')
 			fmt_res := if nofmt { 0 } else { get_fmt_exit_code(vfile, vexe) }
 			match command {
 				'compile' {

cmd/v/help/check-md.txt

@@ -7,6 +7,7 @@ Usage:
 	Note: You can also combine files and directories.
 
 Flags:
+	-silent               Do not show a progress bar.
 	-w, -hide-warnings    Do not print warnings, only errors.
 
 NB: There are several special keywords, which you can put after the code fences for v.