g3/analysis/deps/limitations.md

Analysis Limitations

What Was Observed

Category	Method	Coverage
Crate dependencies	Cargo.toml parsing	Complete
Module structure	mod declarations in lib.rs/main.rs	Complete
File imports	use g3_* and use crate:: patterns	Partial
Submodule structure	mod.rs file inspection	Complete

What Could Not Be Observed

1. Implicit Dependencies

• Trait implementations: A file implementing a trait from another module creates a dependency not captured by use statements
• Type aliases: Types re-exported through pub use chains
• Derive macros: Dependencies introduced by #[derive(...)]

2. Dynamic Patterns

• Trait objects: dyn Trait usage creates runtime dependencies
• Generic bounds: T: SomeTrait constraints
• Associated types: Dependencies through associated type resolution

3. Conditional Compilation

• Platform-specific code: #[cfg(target_os = "...")] blocks not evaluated
• Feature flags: #[cfg(feature = "...")] dependencies not traced
• Test-only code: #[cfg(test)] modules excluded

4. Build System

• build.rs: Build script dependencies not analyzed
• Procedural macros: Macro crate dependencies not traced
• Workspace-level features: Feature unification effects not modeled

5. Excluded Files

Category	Count	Reason
Test files (/tests/)	~40	Out of scope
Example files (/examples/)	~10	Out of scope
Worktree copies	~100	Duplicates

What Was Inferred

Inference	Basis	Confidence
Layer assignment	Topological sort of crate deps	High
Fan-in/fan-out metrics	Edge counting	High
Module-to-file mapping	Naming convention (mod.rs, *.rs)	High
Entrypoints	lib.rs/main.rs presence	High

What May Invalidate Conclusions

1. Hidden re-exports: If g3-core/lib.rs re-exports types from submodules, actual coupling may be higher
2. Macro-generated code: Macros like #[derive(Serialize)] add implicit serde dependency
3. Runtime plugin loading: If any crate loads code dynamically, static analysis misses it
4. Workspace member changes: Adding/removing crates from workspace invalidates crate-level graph

Recommendations for Improved Analysis

1. Use cargo metadata for authoritative crate graph
2. Use cargo tree for transitive dependency analysis
3. Use rust-analyzer for semantic import resolution
4. Parse AST for type references beyond use statements