Add Blockstrings support

[haikusw]

This PR addresses #64 "GraphQL doesn't support 'Blockstrings' which are often used in Descriptions".

There are multiple ways to implement this support and I tried to pick one that matches the existing style of lexing/parsing. Lots of tests are included, though I'm sure more could be thought of.

There's one piece that I just noticed is missing: support for escaped Blockstrings \"""
I'm out of time for this project and don't actually need those (yet), so I'm going to punt on that for now. Shouldn't be terribly difficult, but… ¯_(ツ)_/¯.

I hope you find these contributions acceptable in form and substance. Feel free to let me know if there's things you'd prefer to be done differently.

All my work has been done on macOS 10.15.6 using Xcode 12b5, so I will be interested to see if this builds on linux.

Fixes #64

[haikusw]

oi. Forgot I was going to go back and try to clean up the test function names…

[paulofaria]

Hello, @haikusw. Thank you very much for your contribution! Just so you know, the structure of this repo mainly mirrors the structure of the javascript canonical GraphQL implementation. For your next contributions would be valuable to check how the js counterpart implements what you're after. For example:

https://github.com/graphql/graphql-js/blob/fe3040fffe7f34c8f8b8e1cb849f09138debbfab/src/language/lexer.js#L526

Most of the times a direct "translation" from Typescript do Swift is possible. 🙂

[haikusw]

Hello, @haikusw. Thank you very much for your contribution! Just so you know, the structure of this repo mainly mirrors the structure of the javascript canonical GraphQL implementation. For your next contributions would be valuable to check how the js counterpart implements what you're after. For example:

https://github.com/graphql/graphql-js/blob/fe3040fffe7f34c8f8b8e1cb849f09138debbfab/src/language/lexer.js#L526

Most of the times a direct "translation" from Typescript do Swift is possible. 🙂

Ah, I did not realize this. That does sound like it might have saved some time. Thank you.

[haikusw]

Hello, @haikusw. Thank you very much for your contribution! Just so you know, the structure of this repo mainly mirrors the structure of the javascript canonical GraphQL implementation. For your next contributions would be valuable to check how the js counterpart implements what you're after. For example:
https://github.com/graphql/graphql-js/blob/fe3040fffe7f34c8f8b8e1cb849f09138debbfab/src/language/lexer.js#L526
Most of the times a direct "translation" from Typescript do Swift is possible. 🙂

Ah, I did not realize this. That does sound like it might have saved some time. Thank you.

I see that they did what I did initially which was to make a new .blockstring token type. I ended up backing that out because it would have required a lot of checking for either .string or .blockstring token types for things like description where it can be either. Seems like ideally I would go back and make this set of changes match the canonical GraphQL implementation since that is the essence of what this is. I will try and do that.

[paulofaria]

Seems like ideally I would go back and make this set of changes match the canonical GraphQL implementation since that is the essence of what this is. I will try and do that.

That sounds great!

[haikusw]

done: #68