RepoDiff

RepoDiff is a tool designed to simplify code reviews by generating dynamic git diffs between two commits or branches. It optimizes diffs for analysis by large language models (LLMs) with features like context line adjustment.

Features

• Generate diffs between two commits or branches with a single pass
• Configurable file pattern matching for different file types
• Adjustable context lines per file pattern
• Token counting for estimating LLM query costs
• Combines all changes into a single, well-formatted output
• High performance Rust implementation

Installation

Option 1: Download the Executable

1. Go to the Releases page.
2. Download the latest version of the repodiff.exe executable.
3. Move the repodiff.exe file to a directory included in your system's PATH.

Option 2: Build from Source

Clone the repository and navigate to the directory:

git clone https://github.com/EntityProcess/RepoDiff.git
cd RepoDiff

Build the Rust executable:

# On Windows, run:
cd repodiff
cargo build --release

The compiled binary will be available at target/release/repodiff.exe (Windows) or target/release/repodiff (Linux/macOS).

Usage

Compare Latest Commit with Another Branch

To compare the latest commit in the current branch with the latest common commit in another branch:

repodiff -b main -o output.txt

Compare Two Specific Commits

repodiff -c abc1234 -d 5678def -o output.txt

Parameters:

• -b, --branch: Branch to compare with (e.g., main or master)
• -c, --commit1: First commit hash
• -d, --commit2: Second commit hash
• -o, --output_file: (Optional) Path to the output file. If not provided, the diff will be written to a default file in the system's temporary directory.
• -v, --version: Display the current version of RepoDiff
• -h, --help: Print help information

Configuration

RepoDiff uses a config.json file in the project root directory. Example configuration:

{
  "tiktoken_model": "gpt-4o",
  "filters": [
    {
      "file_pattern": "*.cs",
      "context_lines": 999
    },
    {
      "file_pattern": "*Test*.cs",
      "context_lines": 200
    },
    {
      "file_pattern": "*.xml",
      "context_lines": 10
    },
    {
      "file_pattern": "*",
      "context_lines": 3
    }
  ]
}

Configuration options:

• tiktoken_model: Specifies the language model for token counting (e.g., "gpt-4o").
• filters: An array of filter rules that determine how different files are processed.
  • file_pattern: Glob pattern to match files (e.g., "*.cs", "Test.cs").
  • context_lines: Number of context lines to show around changes (default: 3).

Filter rules are applied in order, with the first matching pattern being used.

Output Format

The tool generates a unified diff format with some enhancements:

1. Standard git diff headers for each file.
2. Modified hunks based on the applied filters:
   • Adjusted context lines based on file patterns
   • Original line numbers preserved

Example output:

diff --git a/src/MyClass.cs b/src/MyClass.cs
--- a/src/MyClass.cs
+++ b/src/MyClass.cs
@@ -10,7 +10,7 @@ public class MyClass
     public void ProcessData(int value)
     {
-        var result = value * 2;
+        var result = value * 3;
         return result;
    }

Prerequisites

• Rust: If building from source, you need Rust installed on your system.
• Git: Required for generating diffs.

Contributing

Contributions are welcome! Please feel free to submit a pull request or open an issue for any bugs or feature requests.