Fix escaping of queries

client.go

@@ -155,7 +155,7 @@ func (c *Client) do(req *Request, via []*Request) (*Response, error) {
 			input, ok := c.GetInput(resp.Meta, resp.Status == StatusSensitiveInput)
 			if ok {
 				req.URL.ForceQuery = true
-				req.URL.RawQuery = url.QueryEscape(input)
+				req.URL.RawQuery = QueryEscape(input)
 				return c.do(req, via)
 			}
 		}

query.go

@@ -0,0 +1,17 @@
+package gemini
+
+import (
+	"net/url"
+	"strings"
+)
+
+// QueryEscape properly escapes a string for use in a Gemini URL query.
+// It is like url.PathEscape except that it also replaces plus signs with their percent-encoded counterpart.
+func QueryEscape(query string) string {
+	return strings.ReplaceAll(url.PathEscape(query), "+", "%2B")
+}
+
+// QueryUnescape is identical to url.PathUnescape.
+func QueryUnescape(query string) (string, error) {
+	return url.PathUnescape(query)
+}

request.go

@@ -51,6 +51,9 @@ func NewRequest(rawurl string) (*Request, error) {
 
 // NewRequestFromURL returns a new request for the given URL.
 // The host is inferred from the URL.
+//
+// Callers should be careful that the URL query is properly escaped.
+// See the documentation for QueryEscape for more information.
 func NewRequestFromURL(url *url.URL) *Request {
 	host := url.Host
 	if url.Port() == "" {