fix: Union type handling - duplication, pointers #184
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This change attempts to address two problems with unmarshaling the results of using GraphQL fragments into two different possible union types. This will hereafter be referred to as "unmarshaling into a union" to keep things short. Those two problems where: 1. If unmarshaling into a union, and the containing Go struct has fields which are pointers to the unioned structs, then the prior implementation would return an error stating `struct field for "<fieldname" doesn't exist in any of 3 places to unmarshal` 2. If unmarshaling into a union, all shared fields of the child union types would be populated in ALL the child fields, not just the child field which had a name maching `__typename`. This led to lots of duplicated data. To accomplish this, I've tried to enrich the information being tracked in the decoder "stacks" so that we can track the name of the field that we're marshaling into and the `__typename` field value in the containing struct. I've added tests for both of the problems described above. Based on discussion from here: hasura#175
hgiasac
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Nov 4, 2025
hgiasac
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LGTM. We may add more test cases, but it's good for now. Added a minor comment.
hgiasac
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Nov 4, 2025
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This change attempts to address two problems with unmarshaling the results of using GraphQL fragments into two different possible union types. This will hereafter be referred to as "unmarshaling into a union" to keep things short. Those two problems where:
struct field for "<fieldname" doesn't exist in any of 3 places to unmarshal__typename. This led to lots of duplicated data.To accomplish this, I've tried to enrich the information being tracked in the decoder "stacks" so that we can track the name of the field that we're marshaling into and the
__typenamefield value in the containing struct.I've added tests for both of the problems described above.
Based on discussion from here:
#175