Steps to reproduce:
1. Create product type with matrix field (no changes, other than adding some rows)
2. Run php bin/console ibexa:graphql:generate-schema command in CLI (at least twice)

Actual result:

 An array element must be followed by a comma. Unexpected token "name" of value "ContentFieldByProduct" ("punctuation" ex
  pected with value ",") around position 56 for expression `resolver("MatrixFieldValue", [value, "matrix_resolver("Content
  FieldByProduct", [value, "matrix_field_65f7f68006d19", args])_65f7f68006d19"])`.

error appears.
This is due to old code in mapToFieldValueResolver (credits to Konrad for finding this ) which replaces some values in fields after schema generation (.ie 'field' value)

Expected result:
I guess certain values in fields should not be replaced (after graphql schema generation).