Add caller func name into type_info.json to make it clear which function is doing wrong

[ghost]

What this pr does

• add caller func name into type_info.json
• this doesn't affect to any original function

Why I do this

I think this is really necessary in a kind of big project.

Let's think if you have a code like this.

def main():
    print(gcd(15, 10))
    print(gcd(24, 10))
    print(gcd("a", "b"))

def gcd(a, b):
    return a, b

This generates type_info like below.

[
    {
        "path": "gcd.py",
        "line": 1,
        "func_name": "main",
        "type_comments": [
            "() -> None"
        ],
        "samples": 1
    },
    {
        "path": "gcd.py",
        "line": 6,
        "func_name": "gcd",
        "type_comments": [
            "(int, int) -> Tuple[int, int]",
            "(str, str) -> Tuple[str, str]"
        ],
        "samples": 3
    }
]

Then, you would come up with the idea like "this gcd function must accept only int. Which function uses in wrong way...?".

However, you can't see any information about that. So you need to dig yourself which code was wrong. I spent the most of time on this while using pyannotate.

Now, this pr will show which code screwed up. This will generate type_info like below

[
    {
        "path": "gcd.py",
        "line": 1,
        "func_name": "main",
        "type_comments": [
            "() -> None"
        ],
        "caller_name": [
            ["__main__ : 7"]
        ],
        "samples": 1
    },
    {
        "path": "gcd.py",
        "line": 6,
        "func_name": "gcd",
        "type_comments": [
            "(int, int) -> Tuple[int, int]",
            "(str, str) -> Tuple[str, str]"
        ],
        "caller_name": [
            [
                "gcd.main : 2",
                "gcd.main : 3"
            ],
            ["gcd.main : 4"]
        ],
        "samples": 3
    }
]

As you see, you can understand (str, str) is called by "gcd.main : 4" easily.

remarks

I submitted Contributor License Agreement.

[ghost]

Fix https://github.com/dropbox/pyannotate/issues/115

[ghost]

@gvanrossum

Sorry if I shouldn't mention you since you are not in dropbox now, but I just love to hear reviews of this pr.

I really love this project but this doesn't seem to be reviewed actively.

[gvanrossum]

You're going to have to find a new maintainer, sorry.

[CLAassistant]

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