Newtype oparg align methods by ShaharNaveh · Pull Request #7403 · RustPython/RustPython

ShaharNaveh

📝 Walkthrough

Walkthrough

This PR refactors the Label oparg type from a tuple struct with direct field access to a newtype with constructor and accessor methods. Multiple oparg types (Label, StoreFastLoadFast, ConstIdx, VarNum, LoadAttr, LoadSuperAttr) are reimplemented using a macro-driven newtype pattern. Call sites across codegen, compiler-core, jit, and vm are systematically updated to use Label::new() constructors and as_u32()/as_usize() accessors instead of tuple field access.

Changes

Cohort / File(s)	Summary
Oparg Type Refactoring `crates/compiler-core/src/bytecode/oparg.rs`	Introduces `newtype_oparg` macro to generate uniform newtypes for oparg types. Replaces ad-hoc Label/StoreFastLoadFast implementations with macro-generated versions. Adds ConstIdx, VarNum, LoadAttr, LoadSuperAttr newtypes and LoadSuperAttrBuilder. All types now include constructor, conversion, and Display impls via macro.
Label Constructor Method Addition `crates/compiler-core/src/bytecode.rs`	Adds `Label::new(u32)` constructor in CodeObject::display_inner call site.
Label API Updates - Codegen & JIT `crates/codegen/src/ir.rs`, `crates/jit/src/instructions.rs`	Replace Label tuple construction `Label(value)` with `Label::new(value)` and field access `.0` with `as_u32()` / `as_usize()` accessors in jump target calculations.
Label API Updates - VM `crates/vm/src/frame.rs`	Systematically update all Label construction and access patterns across jump operations, exception handling, and iterator instructions to use `Label::new()` constructors and `as_u32()` / `as_usize()` accessors.
Instruction Formatting `crates/compiler-core/src/bytecode/instruction.rs`	Adjust fmt_dis macro to format argument without explicit u32 conversion in display output.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

Move OpArg to its own file #6703: Moves/defines Label in oparg module; this PR updates call sites with new Label::new/as_u32 API to match that refactor.
Newtype var_num oparg #7400: Introduces VarNum newtype using similar macro-based oparg machinery; both PRs establish the newtype pattern for opargs.
Rework exception compiler #6909: Modifies Label oparg representation and updates call sites handling Arg<Label>; related refactor of same type's API.

Suggested reviewers

youknowone

Poem

🐰 A Label once lived tuple-free,
With constructor methods, oh what glee!
As_u32() reads its heart so true,
A macro-born newtype, shiny and new!
From codegen to VM, changes all align,
A refactor so neat, it's divine! ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately reflects the main refactoring work: converting oparg types to newtypes with a uniform constructor/accessor method interface.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

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✨ Finishing Touches

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