bin2v: make output compliant to fmt -verify (#6763)

cmd/tools/vbin2v.v

@@ -35,10 +35,9 @@ fn (context Context) header() string {
 	}
 	soptions := options.join(' ')
 	header_s += '// File generated by:\n'
-	header_s += '//    v bin2v $allfiles $soptions\n'
+	header_s += '// v bin2v $allfiles $soptions\n'
 	header_s += '// Please, do not edit this file.\n'
 	header_s += '// Your changes may be overwritten.\n'
-	header_s += '\n'
 	header_s += 'const (\n'
 	return header_s
 }
@@ -47,28 +46,51 @@ fn (context Context) footer() string {
 	return ')\n'
 }
 
-fn (context Context) file2v(file string) string {
+fn (context Context) file2v(bname string, fbytes []byte, bn_max int) string {
 	mut sb := strings.new_builder(1000)
+	bn_diff_len := bn_max - bname.len
+	sb.write('\t${bname}_len' + ' '.repeat(bn_diff_len - 4) + ' = $fbytes.len\n')
+	mut last_len := sb.len
+	fbyte := fbytes[0]
+	sb.write('\t$bname' + ' '.repeat(bn_diff_len) + ' = [byte($fbyte), ')
+	for i := 1; i < fbytes.len; i++ {
+		b := int(fbytes[i]).str()
+		sb_diff_len := sb.len - last_len
+		if i < 30 && sb_diff_len > 86 {
+			sb.write('$b,\n\t\t')
+			last_len = sb.len
+		} else if sb_diff_len > 88 && 92 - sb_diff_len < b.len {
+			sb.write('$b,\n\t\t')
+			last_len = sb.len
+		} else if i == fbytes.len - 1 {
+			sb.write(b)
+		} else {
+			sb.write('$b, ')
+		}
+	}
+	sb.write(']!!\n')
+	return sb.str()
+}
+
+fn (context Context) bname_and_bytes(file string) ?(string, []byte) {
 	fname := os.file_name(file)
 	fname_no_dots := fname.replace('.', '_')
 	byte_name := '$context.prefix$fname_no_dots'.to_lower()
 	fbytes := os.read_bytes(file) or {
-		eprintln('Error: $err')
-		return ''
+		return error('Error: $err')
 	}
-	fbyte := fbytes[0]
-	sb.write('  ${byte_name}_len = $fbytes.len\n')
-	sb.write('  $byte_name = [ byte($fbyte), \n  ')
-	for i := 1; i < fbytes.len; i++ {
-		b := int(fbytes[i]).str()
-		sb.write('${b:4s}, ')
-		if 0 == i % 16 {
-			sb.write('\n  ')
+	return byte_name, fbytes
+}
+
+fn (context Context) max_bname_len(bnames []string) int {
+	mut max := 0
+	for n in bnames {
+		if n.len > max {
+			max = n.len
 		}
 	}
-	sb.write('\n]!!\n')
-	sb.write('\n')
-	return sb.str()
+	// Add 4 to max due to "_len" suffix
+	return max + 4
 }
 
 fn main() {
@@ -99,19 +121,28 @@ fn main() {
 	if !context.write_file.ends_with('.v') {
 		context.write_file += '.v'
 	}
+	mut file_byte_map := map[string][]byte{}
+	for file in real_files {
+		bname, fbytes := context.bname_and_bytes(file) or {
+			eprintln(err)
+			continue
+		}
+		file_byte_map[bname] = fbytes
+	}
+	max_bname := context.max_bname_len(file_byte_map.keys())
 	if context.write_file.len > 0 {
 		mut out_file := os.create(context.write_file) or {
 			panic(err)
 		}
 		out_file.write(context.header())
-		for file in real_files {
-			out_file.write(context.file2v(file))
+		for bname, fbytes in file_byte_map {
+			out_file.write(context.file2v(bname, fbytes, max_bname))
 		}
 		out_file.write(context.footer())
 	} else {
 		println(context.header())
-		for file in real_files {
-			println(context.file2v(file))
+		for bname, fbytes in file_byte_map {
+			println(context.file2v(bname, fbytes, max_bname))
 		}
 		println(context.footer())
 	}