Splice

Span-safe refactoring kernel for Rust using tree-sitter and SQLiteGraph.

Version: 0.2.0 License: GPL-3.0-or-later

What This Is

Splice is a command-line tool that performs byte-accurate, AST-validated refactoring operations on Rust code. It can replace function bodies and delete symbols along with all their references (across files).

What This Is NOT

An IDE - Use Rust Analyzer or IntelliJ Rust
A general-purpose refactoring tool - Focused on specific operations
A complete solution - It's a focused tool for specific jobs
Production-hardened - Use with version control

What It Does

patch: Replace function bodies, struct definitions, enum variants with validation
delete: Remove symbol definitions and all references (cross-file)
Validates syntax with tree-sitter after every operation
Validates compilation with cargo check after every operation
Rolls back atomically on any failure
Orchestrates multi-step refactors via JSON plans

Installation

cargo install splice

Or from source:

git clone https://github.com/oldnordic/splice.git
cd splice
cargo build --release
cp target/release/splice ~/.local/bin/

Quick Start

Delete a Symbol

Delete a function and all its references:

splice delete --file src/lib.rs --symbol helper --kind function

Output:

Deleted 'helper' (3 references + definition) across 2 file(s).

Patch a Symbol

Replace a function body:

cat > new_greet.rs << 'EOF'
pub fn greet(name: &str) -> String {
    format!("Hi, {}!", name)
}
EOF

splice patch --file src/lib.rs --symbol greet --kind function --with new_greet.rs

Multi-Step Plan

cat > plan.json << 'EOF'
{
  "steps": [
    {
      "file": "src/lib.rs",
      "symbol": "foo",
      "kind": "function",
      "with": "patches/foo.rs"
    },
    {
      "file": "src/lib.rs",
      "symbol": "bar",
      "kind": "function",
      "with": "patches/bar.rs"
    }
  ]
}
EOF

splice plan --file plan.json

Commands

splice delete

Remove a symbol definition and all its references.

splice delete --file <PATH> --symbol <NAME> [--kind <KIND>]

Finds references across the entire workspace:

Same-file references (function calls, type mentions)
Cross-file references (via imports)
Handles shadowing (local variables don't count)
Follows re-export chains

splice patch

Apply a patch to a symbol's span.

splice patch --file <PATH> --symbol <NAME> --with <FILE> [--kind <KIND>]

splice plan

Execute a multi-step refactoring plan.

splice plan --file <PLAN.json>

Documentation

manual.md - Complete user manual
CHANGELOG.md - Version history

Requirements

Rust 1.70+ (for building)
Cargo workspace (for validation)

Architecture

src/cli/ - CLI argument parsing
src/ingest/ - Multi-language file parsing (Rust, C/C++, Java, JS, Python, TS)
src/graph/ - SQLiteGraph integration
src/resolve/ - Symbol resolution and reference finding
src/patch/ - Span-safe replacement + validation
src/validate/ - Tree-sitter + cargo check validation
src/plan/ - JSON plan orchestration

Validation Gates

Every operation passes:

UTF-8 boundary validation
Tree-sitter reparse (syntax check)
Cargo check (compilation check)

Testing

cargo test

Test Coverage: 298/298 tests passing

Feedback

If you use this tool and find a bug or miss a feature that would be useful, drop a line. It's appreciated.

License

GPL-3.0-or-later

Disclaimer

This software modifies source code. Always commit your changes before running Splice.

splice 0.2.1