Tuple / array confusion

[fanf2]

I have defined a tuple type like this:

type tuple3 = [ number, string, string ];

The translation I get (with or without --noExtraProps) is:

{
    "$schema": "http://json-schema.org/draft-06/schema#",
    "additionalItems": {
        "anyOf": [
            {
                "type": "number"
            },
            {
                "type": "string"
            },
            {
                "type": "string"
            }
        ]
    },
    "items": [
        {
            "type": "number"
        },
        {
            "type": "string"
        },
        {
            "type": "string"
        }
    ],
    "minItems": 3,
    "type": "array"
}

What I expect is no additionalItems, like this:

{
    "$schema": "http://json-schema.org/draft-06/schema#",
    "items": [
        {
            "type": "number"
        },
        {
            "type": "string"
        },
        {
            "type": "string"
        }
    ],
    "maxItems": 3,
    "minItems": 3,
    "type": "array"
}

[HoldYourWaffle]

It looks like the --noExtraProps handling is missing for tuples:

typescript-json-schema/typescript-json-schema.ts

Lines 386 to 393 in 3b4c20e

	if (targetTupleType.hasRestElement) {
	definition.additionalItems = fixedTypes[fixedTypes.length - 1];
	fixedTypes.splice(fixedTypes.length - 1, 1);
	} else {
	definition.additionalItems = {
	anyOf: fixedTypes
	};
	}

@domoritz Would adding something like this fix the issue?

if (targetTupleType.hasRestElement) { 
    definition.additionalItems = fixedTypes[fixedTypes.length - 1]; 
    fixedTypes.splice(fixedTypes.length - 1, 1); 
} else if (!additionalItems) { //we don't want extra properties
    definition.additionalItems = false; //so we prohibit them
    definition.maxItems = targetTupleType.minLength; //XXX: unsure if 'minLength' should be used here
} else { 
     definition.additionalItems = { 
         anyOf: fixedTypes 
     }; 
}

I can't test it myself because of #284. If this is indeed (part of) the correct solution I'd be more than happy to create a PR for it.

It should probably also be noted that this is essentially a duplicate of vega/ts-json-schema-generator#28. I don't see a reason to add a --strictTuples option to this module since --noExtraProps does pretty much the same. I wouldn't expect my tuples to contain more elements than I ask from them, especially when I explicitly state that I don't want extra properties.

[domoritz]

You can try to send a PR and see what travis says. I am not actively developing this library anymore but review/merge PRs.