Multi-line string support

[normanr]

I'm trying to get multi-line strings (from input I don't control) to work (the README claims "multi-line string literals are allowed", so I'm assuming it should work), but it doesn't seem to:

>>> foo='''{
... "key": "value
... over two lines",
... }'''
>>> import json5
>>> json5.version.VERSION
'0.9.25'
>>> json5.loads(foo)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File ".../site-packages/json5/lib.py", line 108, in loads
    raise ValueError(err)
ValueError: <string>:2 Unexpected "
" at column 14

The built in python json library does support multi-line strings (with strict=False), but can't handle the trailing comma (which is why I'm using json5).

Is there an option to support this? Am I doing something wrong?

Context: I'm trying to parse user data that's currently being parsed with the Newtonsoft.Json c# parser. It seems to accept bare-newlines in json strings 😞

[dpranke]

Hi!

Per the spec, multiline strings in JSON5 (and Javascript, unless you're using template literals) require a line continuation mark ("") at the end of the line to work:

>>> foo='''{
... "key": "value\\
... over two lines",
... }'''
>>> foo
'{\n"key": "value\\\nover two lines",\n}'
>>> import json5
>>> json5.VERSION
'0.9.24'
>>> json5.loads(foo)
{'key': 'valueover two lines'}

So, what you're trying to do by default won't work.

However, it's generally my intent for json5 to mirror the json interface as much as possible, but I guess I somehow missed the strict parameter. I'd be happy to add that, and then I think you'd be okay.

[normanr]

I think adding a strict style parameter would be fine.

Unfortunately I don't control the json I'm parsing and I know it's malformed, but "the Newtonsoft.Json c# parser can parse it fine", so I'm trying to find a Python based parser that can do the same (at least consume the input without raising an exception).

Note that Newtonsoft.Json, doesn't seem to handle line continuation at all: https://dotnetfiddle.net/lHgHvp, but I'm fine with the parsing result being different between Python and c# as I'm not reading the field with the raw newlines anyways.

[dpranke]

Yup, I'll have a fix for this posted in a little bit, just need to write some tests ... :).

[dpranke]

Okay, fixed now in version v0.9.26.