From 6af32885fac7e0819ca3d8ead1e9c161521e77d6 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Tue, 14 May 2024 12:53:54 +0930
Subject: [PATCH] libplugin: add test for dynamic setting values.

Serves as an example, but also shows a quirk which we fix in the next patch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 tests/plugins/test_libplugin.c | 23 +++++++++++++++++++++++
 tests/test_plugin.py           | 19 +++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/tests/plugins/test_libplugin.c b/tests/plugins/test_libplugin.c
index a27ac3a48..b082962e9 100644
--- a/tests/plugins/test_libplugin.c
+++ b/tests/plugins/test_libplugin.c
@@ -9,6 +9,7 @@
 static char *somearg;
 static bool self_disable = false;
 static bool dont_shutdown = false;
+static int dynamic_opt = 7;
 
 static struct command_result *get_ds_done(struct command *cmd,
 					  const char *val,
@@ -177,6 +178,24 @@ static struct command_result *json_checkthis(struct command *cmd,
 	return send_outreq(cmd->plugin, req);
 }
 
+static char *set_dynamic(struct plugin *plugin,
+			 const char *arg,
+			 bool check_only,
+			 int *dynamic_opt)
+{
+	int val = atol(arg);
+
+	/* Whee, let's allow odd */
+	if (val % 2 == 0)
+		return "I don't like \"even\" numbers (valid JSON? Try {})!";
+
+	if (check_only)
+		return NULL;
+
+	*dynamic_opt = val;
+	return NULL;
+}
+
 static const char *init(struct plugin *p,
 			const char *buf UNUSED,
 			const jsmntok_t *config UNUSED)
@@ -293,5 +312,9 @@ int main(int argc, char *argv[])
 				  "flag",
 				  "Whether to timeout when asked to shutdown.",
 				  flag_option, &dont_shutdown),
+		    plugin_option_dynamic("dynamicopt",
+					  "int",
+					  "Set me!",
+					  set_dynamic, &dynamic_opt),
 		    NULL);
 }
diff --git a/tests/test_plugin.py b/tests/test_plugin.py
index 16c9bd931..a4551fddd 100644
--- a/tests/test_plugin.py
+++ b/tests/test_plugin.py
@@ -1560,6 +1560,25 @@ def test_libplugin(node_factory):
     assert l1.rpc.call("helloworld") == {"hello": "NOT FOUND"}
     l1.daemon.wait_for_log("get_ds_bin_done: NOT FOUND")
 
+    # Check dynamic!
+    with pytest.raises(RpcError) as err:
+        l1.rpc.setconfig('dynamicopt', 4)
+    assert err.value.error['message'] == 'I don\'t like \\"even\\" numbers (valid JSON? Try {})!'
+
+    with pytest.raises(RpcError) as err:
+        l1.rpc.check(command_to_check='setconfig', config='dynamicopt', val=4)
+    assert err.value.error['message'] == 'I don\'t like \\"even\\" numbers (valid JSON? Try {})!'
+
+    l1.rpc.check(command_to_check='setconfig', config='dynamicopt', val=9)
+    # FIXME: libplugin doesn't populate defaults!
+    assert 'dynamicopt' not in l1.rpc.listconfigs()['configs']
+
+    l1.rpc.setconfig('dynamicopt', 9)
+    conf = l1.rpc.listconfigs('dynamicopt')['configs']['dynamicopt']
+    assert conf['value_int'] == 9
+    assert conf['plugin'] == plugin
+    assert conf['dynamic'] is True
+
     # Test dynamic startup
     l1.rpc.plugin_stop(plugin)
     # Non-string datastore value: