6: Fix parser type safety for stricter AST types#255
Merged
Cito merged 6 commits intographql-python:mainfrom Jan 8, 2026
Merged
6: Fix parser type safety for stricter AST types#255Cito merged 6 commits intographql-python:mainfrom
Cito merged 6 commits intographql-python:mainfrom
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Introduce benchmarks using a large (~117KB) GraphQL query to measure parse and pickle serialization performance. These provide a baseline for comparing serialization approaches in subsequent commits. Baseline performance (measrued on a Macbook Pro M4 Max): - Parse: 81ms - Pickle encode: 24ms - Pickle decode: 42ms - Roundtrip: 71ms
Prepares AST for immutability by using tuples instead of lists for collection fields. This aligns with the JavaScript GraphQL library which uses readonly arrays, and enables future frozen datastructures.
Python 3.9 reaches end-of-life October 2025. Python 3.10 adoption is now mainstream - major frameworks (strawberry, Django 5.0, FastAPI) require it. This enables modern Python features: - Dataclasses with `kw_only` - Union types with `|` syntax (PEP 604) - isinstance() with union types directly - match statements for pattern matching
Modifies the AST visitor to use copy-on-write semantics when applying edits. Instead of mutating nodes in place, the visitor now creates new node instances with the edited values. This prepares for frozen AST nodes while maintaining backwards compatibility. The visitor accumulates edits and applies them by constructing new nodes, enabling the transition to immutable data structures.
- Update test_visitor.py to properly type-annotate the visitor class attribute and add assertion before using selection_set - Update test_schema_parser.py to use more precise types that match GraphQL spec: - NonNullTypeNode's inner type can only be NamedTypeNode or ListTypeNode - Schema definitions use ConstDirectiveNode, not DirectiveNode - Default values use ConstValueNode, not ValueNode - OperationTypeDefinition's type_ must be NamedTypeNode
- Handle token.value being str | None by using `or ""` fallback - Fix parse_variable_definition to not use `and` for side effects - Use properly typed variable in parse_nullability_assertion - These fixes prepare for stricter type checking in frozen dataclasses
corydolphin
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Merging this PR will not alter performanceSummary
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Cito
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Jan 8, 2026
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Fixes a number of type-safety issues which would be revealed when we make the AST nodes strictly typed.