indent interface is different from python stdlib

[AnjoMan]

Using python's native json encoder, I can do

# json with no indentation
>>> json.dumps({"foo": 1, "baz": 2}, indent=0)
'{\n"foo": 1,\n"baz": 2}'

# output is all on one line
>>> json.dumps({"foo": 1, "baz": 2}, indent=None)
'{"foo": 1, "baz": 2}'

However, with ujson i get different behaviour with both of these

# ujson gives me output all on one line when i specify 0 indentation
>>> ujson.dumps({"foo": 1, "baz": 2}, indent=0)
'{"foo": 1, "baz": 2}'

# ujson fails if I pass in None
>>> ujson.dumps({"foo": 1, "baz": 2}, indent=None)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-8-e18a04872c22> in <module>()
----> 1 ujson.dumps({"foo": 1, "baz": 2}, indent=None)

TypeError: an integer is required (got type NoneType)

[AnjoMan]

Is there interest in fixing this? I would be willing to poke around and try to find a solution, but not if it isn't a welcome change. I could use a hint about where to start though, as I've never worked with python bindings to c before.

[hugovk]

@AnjoMan Hello! If you're still interested, looks like this is the relevant chunk:

ultrajson/lib/ultrajsonenc.c

Lines 508 to 520 in 7c60d47

	static void Buffer_AppendIndentNewlineUnchecked(JSONObjectEncoder *enc)
	{
	if (enc->indent > 0) Buffer_AppendCharUnchecked(enc, '\n');
	}
	static void Buffer_AppendIndentUnchecked(JSONObjectEncoder *enc, JSINT32 value)
	{
	int i;
	if (enc->indent > 0)
	while (value-- > 0)
	for (i = 0; i < enc->indent; i++)
	Buffer_AppendCharUnchecked(enc, ' ');
	}

And it should do this, to handle non-integers:

If indent is a non-negative integer or string, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0, negative, or "" will only insert newlines. None (the default) selects the most compact representation. Using a positive integer indent indents that many spaces per level. If indent is a string (such as "\t"), that string is used to indent each level.

https://docs.python.org/3/library/json.html#basic-usage