From c7cefa9ce685aebd5fdf47b186bf1235340dbd0b Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@vlang.io>
Date: Sun, 29 Nov 2020 17:45:22 +0100
Subject: [PATCH] json: fix encoding pointers

---
 vlib/json/json_test.v | 8 +++++++-
 vlib/v/gen/fn.v       | 6 +++++-
 vlib/v/gen/json.v     | 3 ++-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/vlib/json/json_test.v b/vlib/json/json_test.v
index 27caccd17c..d49827692f 100644
--- a/vlib/json/json_test.v
+++ b/vlib/json/json_test.v
@@ -76,8 +76,12 @@ fn test_parse_user() {
 	assert u.pets == '{"name":"Bob","animal":"Dog"}'
 }
 
+fn (mut u User) foo() string {
+	return json.encode(u)
+}
+
 fn test_encode_user() {
-	usr := User{
+	mut usr := User{
 		age: 10
 		nums: [1, 2, 3]
 		last_name: 'Johnson'
@@ -89,6 +93,8 @@ fn test_encode_user() {
 	out := json.encode(usr)
 	println(out)
 	assert out == expected
+	// Test json.encode on mutable pointers
+	assert usr.foo() == expected
 }
 
 struct Color {
diff --git a/vlib/v/gen/fn.v b/vlib/v/gen/fn.v
index 70b5f63ad1..b05738db9d 100644
--- a/vlib/v/gen/fn.v
+++ b/vlib/v/gen/fn.v
@@ -483,10 +483,14 @@ fn (mut g Gen) fn_call(node ast.CallExpr) {
 			g.gen_json_for_type(node.args[0].typ)
 			json_type_str = g.typ(node.args[0].typ)
 			// `json__encode` => `json__encode_User`
-			encode_name := c_name(name) + '_' + util.no_dots(json_type_str)
+			// encode_name := c_name(name) + '_' + util.no_dots(json_type_str)
+			encode_name := js_enc_name(json_type_str)
 			g.writeln('// json.encode')
 			g.write('cJSON* $json_obj = ${encode_name}(')
 			// g.call_args(node.args, node.expected_arg_types) // , [])
+			if node.args[0].typ.is_ptr() {
+				g.write('*')
+			}
 			g.call_args(node)
 			g.writeln(');')
 			tmp2 = g.new_tmp_var()
diff --git a/vlib/v/gen/json.v b/vlib/v/gen/json.v
index 8d34e1677f..f6caf551a3 100644
--- a/vlib/v/gen/json.v
+++ b/vlib/v/gen/json.v
@@ -139,7 +139,8 @@ $enc_fn_dec {
 }
 
 fn js_enc_name(typ string) string {
-	name := 'json__encode_$typ'
+	suffix := if typ.ends_with('*') { typ.replace('*', '') } else { typ }
+	name := 'json__encode_$suffix'
 	return util.no_dots(name)
 }