clang-format a json file

Question

I have a json file. If I run clang-format on it, it formats it as though it's code (ugly).

{
  "name" : "My great app",
           "description" : "It's really cool.",
                           "version" : "0.0.1"
}

If I put 'foo = ' at the start of the file, it's great, but it's not json anymore.

foo = {
  "name" : "My great app",
  "description" : "It's really cool.",
  "version" : "0.0.1"
}

How can I get clang-format to format the bare object in the json file as in the second example?

you could prefix the file with `foo =`, run clang-format and then remove the prefix. — Igwe Kalu, Mar 08 '16 at 00:09
JSON is a format, not a data type of something. U can use native objects and then stringify them to json. — loadaverage, Mar 08 '16 at 00:49
Here's some other options: https://stackoverflow.com/questions/352098/how-can-i-pretty-print-json-in-unix-shell-script — PythonJin, Jun 20 '17 at 05:32

score 3 · Answer 1 · answered Jun 22 '21 at 07:36

3

I've been working on getting this accepted, https://reviews.llvm.org/D93528, this does what you suggest by adding a hidden "x = " at the front of the file, then remove that after formatting using the replacement mechanism.

Until this gets landed I think you could do something similar perhaps with clang-apply-replacements

answered Jun 22 '21 at 07:36

MyDeveloperDay

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Do you have (or know about others) any plans to improve support for JSON formatting via clang-format? I've just tried it in LLVM 13, it seems that only `IndentWidth` option is supported. – αλεχολυτ Dec 23 '21 at 08:03
What else wold you want? – MyDeveloperDay Dec 24 '21 at 15:41
In particular spaces around `:` – αλεχολυτ Dec 24 '21 at 20:02

zmo · Accepted Answer · 2016-03-08T00:29:00.773

Personally I'd do it using python, using the json's package pretty printer:

cat mydata.json | python -mjson.tool

and if you don't like the defaults:

cat mydata.json | python -c 'import json, sys; print(json.dumps(json.load(sys.stdin), indent=4, sort_keys=True))'

Otherwise, I don't have clang-format installed, and for the sake of pretty printing, I'd rather use an existing tool.

N.B.: You can also do it within vim and use the == normal command on the full file selection ☺

score 2 · Answer 3 · answered Apr 21 '16 at 20:45

2

Another program that I like to use is jq. It's pretty easy to use, and the documentation is great. For example, for simple reformatting you can do this:

jq . test.json

answered Apr 21 '16 at 20:45

PythonJin

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score 0 · Answer 4 · answered Jun 20 '17 at 05:34

0

If you have json_pp on your system you can also do:

cat test.json | json_pp

answered Jun 20 '17 at 05:34

PythonJin

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clang-format a json file

4 Answers4