util.format: Tweak serialization of %q formatted entries

Improves serialization of function references especially, the built-in
default handling of that in util.serialization is not the most
informative.  Now, along with the function metatable from util.startup,
the actual function can be found by filename and line number.

1 files changed, 8 insertions, 1 deletions

diff --git a/util/format.lua b/util/format.lua
index caeada63..e07f5f2f 100644
--- a/util/format.lua
+++ b/util/format.lua
@@ -10,7 +10,14 @@ local unpack = table.unpack;
 local pack = table.pack;
 local valid_utf8 = require "prosody.util.encodings".utf8.valid;
 local type = type;
-local dump = require "prosody.util.serialization".new("debug");
+local dump = require"prosody.util.serialization".new({
+	preset = "compact";
+	fallback = function(v, why)
+		return "_[[" .. (why or tostring(v)) .. "]] ";
+	end;
+	fatal = false;
+	maxdepth = 5;
+});
 local num_type = math.type;
 
 -- In Lua 5.3+ these formats throw an error if given a float