Location columns should be started from 1 instead of 0

[KvanTTT]

Steps to reproduce

Consider the parsing of the following simple code on esprima demo page with checked Line and column-based option.

a

Expected output

{
    "type": "Program",
    "body": [
        {
            "type": "ExpressionStatement",
            "expression": {
                "type": "Identifier",
                "name": "a",
                "loc": {
                    "start": {
                        "line": 1,
                        "column": 1
                    },
                    "end": {
                        "line": 1,
                        "column": 2
                    }
                }
            },
            "loc": {
                "start": {
                    "line": 1,
                    "column": 1
                },
                "end": {
                    "line": 1,
                    "column": 2
                }
            }
        }
    ],
    "sourceType": "script",
    "loc": {
        "start": {
            "line": 1,
            "column": 1
        },
        "end": {
            "line": 1,
            "column": 2
        }
    }
}

Actual output

{
    "type": "Program",
    "body": [
        {
            "type": "ExpressionStatement",
            "expression": {
                "type": "Identifier",
                "name": "a",
                "loc": {
                    "start": {
                        "line": 1,
                        "column": 0
                    },
                    "end": {
                        "line": 1,
                        "column": 1
                    }
                }
            },
            "loc": {
                "start": {
                    "line": 1,
                    "column": 0
                },
                "end": {
                    "line": 1,
                    "column": 1
                }
            }
        }
    ],
    "sourceType": "script",
    "loc": {
        "start": {
            "line": 1,
            "column": 0
        },
        "end": {
            "line": 1,
            "column": 1
        }
    }
}

It unifies location between esprima library and common code editors (VS Code, Notepad++).

[ariya]

Thanks for the report! Unfortunately, it is designed like that for historical reason (the AST is originated from SpiderMonkey AST format) and now the cost is too high to break the downstream tools relying on the behavior. See estree/estree#65 for some more details.