Exception when parsing JSDocFunctionType

[bradzacher]

What code were you trying to parse?

var a: function(b): c;

What actually happened?

Cannot set property 'typeAnnotation' of null

I haven't debugged this at all, but I assume it's because the variable's type declaration is of kind JSDocFunctionType, which we do not have any handling for.

https://astexplorer.net/#/gist/a1a5bcad94191c0d730eb920ced2e24b/f10df5321aaf8ceef561d14ce57a0ab59eee0ac5

[armano2]

This syntax is invalid if used in code, typescript reports error code 8020,

error happens when we are trying to convert b -> Parameter

typescript does not return correct ast node (there is no name) and parameter is created as null

typescript-eslint/packages/typescript-estree/src/convert.ts

Lines 1364 to 1372 in 348d2f6

	} else {
	parameter = result = this.convertChild(node.name, parent);
	}
	if (node.type) {
	parameter.typeAnnotation = this.convertTypeAnnotation(
	node.type,
	node,
	);

we should enable error code 8020

[armano2]

what do you think about throwing parse error when we encounter nodes from range FirstJSDocNode and LastJSDocNode? as this is going to to produce incorrect ast anyway (in unexpected ways).

[bradzacher]

I don't see why not - it's a TS error anyways.