Initial project import

tools/v/vlib/v3/errors/details.v

@@ -0,0 +1,40 @@
+module errors
+
+import os
+import v3.token
+
+pub fn details(file &token.File, pos token.Position, row_padding int) string {
+	if file.name == '' {
+		return 'at ${pos.line}:${pos.column}'
+	}
+	src := os.read_file(file.name) or { return 'at ${pos.line}:${pos.column} in `${file.name}`' }
+	line_start := if pos.line - row_padding - 1 > 0 {
+		file.line_start(pos.line - row_padding)
+	} else {
+		0
+	}
+	mut line_end := pos.offset + 1
+	for i := 0; line_end < src.len; {
+		if src[line_end] == `\n` {
+			i++
+			if i == row_padding + 1 {
+				break
+			}
+		}
+		line_end++
+	}
+	lines_src := src[line_start..line_end].split('\n')
+	line_no_start, _ := file.find_line_and_column(line_start)
+	mut lines_src_formatted := []string{}
+	for i in 0 .. lines_src.len {
+		line_no := line_no_start + i
+		line_src := lines_src[i]
+		line_spaces := line_src.replace('\t', '    ')
+		lines_src_formatted << '${line_no:5d} | ' + line_spaces
+		if line_no == pos.line {
+			space_diff := line_spaces.len - line_src.len
+			lines_src_formatted << '        ' + ' '.repeat(space_diff + pos.column - 1) + '^'
+		}
+	}
+	return lines_src_formatted.join('\n')
+}