Refactor workflow macro and enhance composite arm handling

[aitoroses]

Summary

This PR introduces a significant refactoring of the workflow macro in floxide-macros and related components. The primary goals of these changes are to improve code clarity, enhance type safety, and streamline the handling of edge definitions, particularly for composite arms.

Key improvements include:

• Refactored Workflow Macro: The workflow macro has been simplified by:
  • Consolidating imports and identifier generation.
  • Streamlining the handling of direct and composite edges.
  • Improving pattern matching logic for composite arms, including support for guards and wildcard bindings.
• Enhanced Type Safety: Compile-time trait-based assertions have been introduced to ensure type compatibility between connected nodes. This provides clearer error messages that include the names of the involved nodes when a type mismatch occurs.
• New floxide-macros-support Crate: A new crate, floxide-macros-support, has been created to house shared data structures and parsing logic for the macros, promoting better code organization and reusability.
• Improved Test Coverage:
  • New tests have been added to specifically verify the compile-time type mismatch errors.
  • Tests for composite arm parsing have been added to ensure various syntaxes (unit, binding, wildcard, with/without guards) are handled correctly.
• Updated Examples and Documentation: Documentation examples in retry.rs and lib.rs have been updated to reflect the latest API changes and best practices, including the use of SharedState. The branching example now returns meaningful output.

Changes by Crate

floxide-macros

• workflow.rs:
  • Major refactoring of the macro parsing and code generation logic.
  • Moved WorkflowDef, EdgeKind, and CompositeArm to floxide-macros-support.
  • Simplified direct edge handling.
  • Enhanced composite arm pattern matching with support for unit variants, bindings, wildcards, and guards.
  • Added compile-time type assertions for direct edges to catch type mismatches between connected nodes.
• Cargo.toml:
  • Added floxide-macros-support as a dependency.
  • Added trybuild as a dev-dependency for compile-fail tests.
• Tests:
  • Added tests/compile_fail_tests.rs with type_mismatch.rs UI test.
  • Added tests/composite_arms.rs to test parsing of various composite arm syntaxes.
  • Updated tests/workflow.rs to reflect new syntax and remove unnecessary bindings in composite arms.

floxide-macros-support (New Crate)

• Contains the definitions for WorkflowDef, EdgeKind, CompositeArm, and the associated parsing logic, extracted from floxide-macros/src/workflow.rs.
• Improved parsing logic for clarity and maintainability.

examples/branching_example.rs

• Updated node output types to String to provide more meaningful return values.
• Adjusted assertions in the example run to match the new output.
• Updated composite arm syntax to use wildcards (_) where bindings are not needed.

src/lib.rs

• Updated the main library example to use SharedState for the context and reflect changes in node output types.

Detailed Commit History

• Refactor workflow macro to streamline edge handling:
  • Simplified direct edge handling with if-let.
  • Removed unnecessary else branches in pattern matching.
  • Maintained type assertion generation.
• Refactor workflow macro and improve test cases:
  • Consolidated imports and streamlined identifier generation.
  • Updated test file formatting.
  • Enhanced parsing logic in floxide-macros-support.
• Update documentation examples in retry and lib modules:
  • Ignored compilation errors in retry.rs doc example.
  • Updated lib.rs example with SharedState and Node.
• Enhance type assertion in workflow macro and add compile-time tests:
  • Improved type assertions to include node names in error messages.
  • Added type_mismatch.rs compile-fail test.
• Refactor workflow macro and enhance pattern matching:
  • Consolidated composite arm handling and improved pattern matching.
  • Corrected BatchAction::Small parameter handling.
• Update floxide-macros dependencies and refine workflow macro:
  • Added floxide-macros-support dependency.
  • Refined pattern matching in branch actions.
• Update dependencies and enhance floxide-macros functionality:
  • Added various new dependencies in Cargo.lock.
  • Added trybuild dev-dependency.
  • Included type assertions for direct edges.
  • Fixed wildcard assertion in composite_arms.rs tests.
• Add floxide-macros-support crate and integrate with floxide-macros:
  • Created floxide-macros-support crate.
  • Integrated it into floxide-macros.
  • Added composite arm tests.
  • Modified example workflow output.

This refactoring aims to make the workflow definition more robust, easier to understand, and less error-prone.