From e8d5a6f479876a5dcc9dca1ccd9282abb8459003 Mon Sep 17 00:00:00 2001
From: huzedong1 <huzedong1@momenta.ai>
Date: Wed, 15 Mar 2023 14:52:19 +0800
Subject: [PATCH] perf: use strings.Builder in GoString

---
 errors.go | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/errors.go b/errors.go
index deaded8..193e89b 100644
--- a/errors.go
+++ b/errors.go
@@ -98,16 +98,23 @@ func (ve *ValidationError) Error() string {
 	return fmt.Sprintf("jsonschema: %s does not validate with %s: %s", quote(leaf.InstanceLocation), u+"#"+leaf.KeywordLocation, leaf.Message)
 }
 
-func (ve *ValidationError) GoString() string {
+func (ve *ValidationError) goStringTo(tgt *strings.Builder, indent int) {
 	sloc := ve.AbsoluteKeywordLocation
 	sloc = sloc[strings.IndexByte(sloc, '#')+1:]
-	msg := fmt.Sprintf("[I#%s] [S#%s] %s", ve.InstanceLocation, sloc, ve.Message)
+	for i := 0; i < indent; i++ {
+		tgt.WriteByte(' ')
+	}
+	tgt.WriteString(fmt.Sprintf("[I#%s] [S#%s] %s", ve.InstanceLocation, sloc, ve.Message))
 	for _, c := range ve.Causes {
-		for _, line := range strings.Split(c.GoString(), "\n") {
-			msg += "\n  " + line
-		}
+		tgt.WriteByte('\n')
+		c.goStringTo(tgt, indent+2)
 	}
-	return msg
+}
+
+func (ve *ValidationError) GoString() string {
+	var msgBuf strings.Builder
+	ve.goStringTo(&msgBuf, 0)
+	return msgBuf.String()
 }
 
 func joinPtr(ptr1, ptr2 string) string {