feat(markdown): custom error display

1 files changed, 38 insertions, 0 deletions

diff --git a/mardown/error.go b/mardown/error.go
new file mode 100644
index 0000000..f85dfbb
--- /dev/null
+++ b/mardown/error.go
@@ -0,0 +1,38 @@
+package mardown
+
+import "fmt"
+
+type ParseError struct {
+	internal error
+	lxs      lexers
+}
+
+func (e *ParseError) Error() string {
+	return e.internal.Error()
+}
+
+func (e *ParseError) Pretty() string {
+	lxs := e.lxs
+	if lxs.lexers == nil {
+		return e.internal.Error()
+	}
+	current := lxs.current - 1
+	for lxs.Before() && lxs.Current().Type != lexerBreak {
+	}
+	current -= lxs.current
+	contxt := ""
+	ind := ""
+	for lxs.Next() && lxs.Current().Type != lexerBreak {
+		contxt += lxs.Current().Value
+		if lxs.current < current {
+			if lxs.current == current-2 {
+				ind += "^"
+			} else {
+				for range len(lxs.Current().Value) {
+					ind += "~"
+				}
+			}
+		}
+	}
+	return fmt.Sprintf("%v\n\n%s\n%s", e, contxt, ind)
+}