graphql/graphql-js

merge ast trees

Open

#1428 opened on Jul 21, 2018

View on GitHub
 (9 comments) (4 reactions) (0 assignees)TypeScript (19,825 stars) (2,223 forks)batch import
help wantedproposal

Description

Feature request

Another feature that is extremely useful and utils are lacking it: merging ast trees.

Primary use case: merging two queries (selections) to dynamically construct queries. There are plenty of cases where it is needed, mainly in libraries and in cases of graphql to graphql communication.

PS It would be great if somebody can say how to do this properly now (simple deep merge doesn't wotk properly)

Contributor guide

Tech stack
typescript
Domain
apibackend
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
3-5 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
GraphQL conceptsAST traversal knowledge
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
35
Research direction
Review the existing AST utilities in graphql js, particularly in src/utilities/ directory, to understand current functions like concatAST. Examine the issue comments for prior discussions and attempts. Develop a deep merge algorithm for AST nodes, handling selection sets, fragments, and directives while preserving unique fields and avoiding duplicates.