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+# CRAB: Code Review Automated Benchmark
+
+CRAB (Code Review Automated Benchmark) is a high-quality dataset and extraction pipeline designed to evaluate automated code-review tools on two complementary tasks:
+
+1. **Review Comment Generation**
+ Given a code snapshot before review, generate natural-language comments emulating human reviewers.
+1. **Code Refinement (Revised Code Generation)**
+ Given the same snapshot plus a reviewer’s comment, generate the revised code implementing that feedback.
+
+CRAB focuses on **Java** projects, rigorously curating pull-request “triplets” of
+
+- **submitted_code** (pre-review code)
+- **reviewer_comment** (validated natural-language feedback, with paraphrases)
+- **revised_code** (post-review implementation, validated via tests)
+
+______________________________________________________________________
+
+## Features
+
+- **Automated Extraction Pipeline** (`pull_requests.py`)
+
+ - Clones GitHub repositories, locates PRs with a single review comment, and extracts diffs before/after the comment
+ - Builds and tests each snapshot in Docker (Maven & Gradle support)
+ - Generates JaCoCo coverage reports to ensure revised code covers the commented lines
+
+- **Manual Validation Tools** (`manual_selection.py`)
+
+ - Interactive review to mark whether comments suggest changes and whether post-comment diffs address them
+
+- **Serialization & Task Extraction** (`dataset.py`, `extract_correct_predictions.py`)
+
+ - Produce JSON datasets for:
+
+ - **Full** (all validated triplets)
+ - **Comment Generation**
+ - **Code Refinement**
+ - **Web App** export format
+
+- **Utility Modules**
+
+ - **`handlers.py`**: abstract and concrete build/test handlers (Maven, Gradle)
+ - **`utils.py`**: Git/GitHub helpers, BLEU-based paraphrase filtering, logging
+
+______________________________________________________________________
+
+## Installation
+
+1. **Clone this repository**
+
+ ```bash
+ git clone https://github.com/your-org/crab
+ cd crab
+ ```
+
+1. **Install Python dependencies**
+
+ ```bash
+ pip install -r requirements.txt
+ ```
+
+ The pipeline depends on:
+
+ - `pandas`, `tqdm`, `docker`, `beautifulsoup4`, `unidiff`, `PyGithub`, `javalang`
+
+1. **Docker images**
+
+ - Build or pull the two images used by the handlers:
+
+ - `crab-maven` (for Maven projects)
+ - `crab-gradle` (for Gradle projects)
+
+______________________________________________________________________
+
+## Usage
+
+Run the script to generate the CRAB dataset triplets:
+
+```sh
+python pull_requests.py [CSV_FILE] [options]
+```
+
+- **CSV_FILE**: Path to the input CSV listing repositories (output of `clone_repos.py`).
+
+### Options
+
+| Parameter | Type | Default | Required | Description |
+| ----------------------------- | ------- | --------------------- | -------- | --------------------------------------------------------------------------------------------------------- |
+| `CSV_FILE` | string | — | Yes | The CSV file containing the list of GitHub repos to process. |
+| `-o`, `--output` | string | `./dataset.json` | No | Path where the resulting JSON dataset will be saved. |
+| `-r`, `--repos` | string | `./results/` | No | Directory under which repos will be (or already are) cloned. |
+| `-c`, `--cache` | string | *None* | No | Path to a previous run’s JSON output to resume from (caches processed PRs). |
+| `-a`, `--archive-destination` | string | `./dataset/archives` | No | Directory where per-PR archives (tar.gz) will be stored. |
+| `-s`, `--sort-by` | string | *None* | No | Column name in the CSV by which to sort repos before processing. |
+| `--only-repo` | string | *None* | No | Process only the specified repo (format: `owner/name`), ignoring all others in the CSV. |
+| `--cache-requests` | flag | `false` | No | If set, caches GitHub API requests (using `requests_cache`) to speed up reruns at the risk of stale data. |
+| `--max-workers` | integer | *None* (monothreaded) | No | Number of parallel workers for processing repos. If omitted, the script runs in a single thread. |
+
+````
+
+**Example**
+
+```sh
+python pull_requests.py my_repos.csv \
+ --output=data/triplets.json \
+ --repos=./cloned_repos/ \
+ --archive-destination=./archives/ \
+ --cache-requests \
+ --max-workers=4
+````
+
+This will:
+
+1. Read `my_repos.csv` for the list of GitHub repositories.
+1. Clone any missing repos under `./cloned_repos/`.
+1. Process each pull request, archiving the base and merged states under `./archives/`.
+1. Save the combined dataset to `data/triplets.json`.
+1. Cache GitHub API calls for faster subsequent runs.
+1. Use 4 parallel workers to speed up processing.
+
+### 2. Run manual validation
+
+Run the manual selection script to validate or refine your dataset entries:
+
+```sh
+python manual_selection.py [DATASET_FILE] -o OUTPUT [options]
+```
+
+- **DATASET_FILE**: Path to the input JSON dataset (e.g. output of your preprocessing step).
+- **-o, --output**: Path where the updated dataset JSON will be saved.
+
+### Options
+
+| Parameter | Type | Default | Required | Description |
+| ------------------------ | --------------------- | --------- | -------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `DATASET_FILE` | string | — | Yes | Path to the dataset JSON file to process. |
+| `-o`, `--output` | string | — | Yes | Path where the resulting dataset (after manual selection/refinement) will be written. |
+| `--overwrite` | flag | *false* | No | If set, re-evaluates and overwrites any existing `Selection` entries in the dataset. |
+| `-m`, `--mode` | `ValidationMode` enum | `comment` | No | Validation mode to run in:
• `comment` – only check if comments suggest a change.
• `refinement` – check comment suggestions and whether diffs implement them. |
+| `--check-diff-relevance` | flag | *false* | No | If set (only in `refinement` mode), first ask whether each diff is related to the comment before prompting for refinement. |
+
+### 3. Serialize to JSON for modeling
+
+Load and process a dataset JSON, optionally add paraphrases, and serialize it in various formats:
+
+```sh
+python dataset.py [FILENAME] [options]
+```
+
+- **FILENAME**: Path to the input JSON file to load (e.g., output of a previous run).
+
+### Options
+
+| Parameter | Type | Default | Required | Description |
+| ------------------------- | ----------------- | ------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `FILENAME` | string | — | Yes | Path to the dataset JSON file to load. |
+| `-o`, `--output` | string | `output.json` | No | Path where the processed dataset (or archive) will be saved. |
+| `-p`, `--paraphrases` | string | *None* | No | CSV file containing generated paraphrases. Must include a `paraphrases` column with lines of the form `Paraphrase#N: `. When provided, each paraphrase will be scored and (optionally) appended to its comment. |
+| `-t`, `--output_type` | `OutputType` enum | `full` | No | Type of output to generate:
• `full` – dump the entire dataset as JSON.
• `comment_gen` – dump only entries whose comments suggest changes, as a ZIP of JSON (with `_with_context` or `_no_context`).
• `code_refinement` – dump entries both covered and addressed, as a ZIP.
• `webapp` – dump minimal fields for webapp. |
+| `-a`, `--archives` | string | *None* | No | Root directory where per-PR archives (tar.gz) live. Relevant only for `comment_gen` or `code_refinement` outputs; will be bundled into the ZIP under `context/`. |
+| `--remove-non-suggesting` | flag | *false* | No | When output type is `full`, drop entries whose comments do *not* suggest a change. |
+
+### Examples
+
+**Basic full dump:**
+
+```sh
+python dataset.py data/raw_dataset.json
+```
+
+**Add paraphrases and overwrite default output path:**
+
+```sh
+python dataset.py data/raw_dataset.json \
+ -o data/with_paraphrases.json \
+ -p paraphrases.csv
+```
+
+**Generate a ZIP for code-refinement with context archives:**
+
+```sh
+python dataset.py data/raw_dataset.json \
+ -o outputs/code_refinement.zip \
+ -t code_refinement \
+ -a ./archives/
+```
+
+This will:
+
+1. Load `data/raw_dataset.json` into memory.
+1. If `-p paraphrases.csv` is given, read paraphrases, score them, and append non-redundant ones to each comment.
+1. Serialize entries according to `--output_type`.
+1. Bundle required archives (if any) into the resulting ZIP or write JSON to the specified `--output`.
+
+### 4. Extract “ground truth” references
+
+Run the script to extract “exact prediction” JSONs for comment‐generation, code‐refinement, or paraphrase tasks:
+
+```sh
+python extract_correct_predictions.py DATASET_JSON [options]
+```
+
+- **DATASET_JSON**: Path to the input dataset JSON file.
+
+### Options
+
+| Parameter | Type | Default | Required | Description |
+| --------------------- | ----------------- | ------------------------------- | -------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| `DATASET_JSON` | string | — | Yes | Path to the dataset JSON to process. |
+| `-o`, `--output` | string | `exact_predictions_.json` | No | Path for the output JSON file. If omitted, defaults to `exact_predictions_.json`. |
+| `-a`, `--archives` | string | — | Only for `code_refinement` | Directory where per-PR tar.gz archives live. Required when `--output-type=code_refinement` so merged file contents can be extracted. |
+| `-t`, `--output-type` | `OutputType` enum | `comment_gen` | No | Which extraction to perform:
• `comment_gen` – pull file+location+body for commenting tasks.
• `code_refinement` – extract post-merge file contents for code tasks.
• `paraphrases` – dump comments+before-PR files for paraphrase creation. |
+
+### OutputType Values
+
+| Name | Value | Meaning |
+| ----------------- | ----------------- | ----------------------------------------------------------------------------------------------------------- |
+| `COMMENT_GEN` | `comment_gen` | Extracts predicted comment locations & bodies to feed a comment‐generation model. |
+| `CODE_REFINEMENT` | `code_refinement` | Extracts merged file snapshots for entries that both cover and address changes, to feed a refinement model. |
+| `FOR_PARAPHRASES` | `paraphrases` | Extracts original comments plus “before-PR” file contents for paraphrase generation. |
+
+### Examples
+
+**1. Default comment-generation extraction**
+
+```sh
+python extract_correct_predictions.py data/dataset.json \
+ -o predictions_comment.json
+```
+
+This reads `data/dataset.json` and writes all entries whose comments suggest changes to `predictions_comment.json`.
+
+______________________________________________________________________
+
+**2. Code-refinement extraction**
+
+```sh
+python extract_correct_predictions.py data/dataset.json \
+ --output refined_files.json \
+ --output-type code_refinement \
+ --archives ./archives/
+```
+
+This will locate each merged PR archive under `./archives/`, extract the post-merge file contents for entries that both cover and address changes, and save them to `refined_files.json`.
+
+______________________________________________________________________
+
+**3. Paraphrase data extraction**
+
+```sh
+python extract_correct_predictions.py data/dataset.json \
+ -t paraphrases \
+ -o comments_for_para.json
+```
+
+This dumps comment bodies plus “before-PR” file snapshots for all entries suggesting changes, suitable for paraphrase modeling.
+
+______________________________________________________________________
+
+## Contributing
+
+1. **Issue Tracker**: Please file issues for bugs or feature requests.
+1. **Pull Requests**: Fork, create a topic branch, and submit a PR. Please include tests or validations where applicable.
+1. **Extending Build Support**: To add a new build system (e.g., Ant, Bazel), subclass `BuildHandler` in `handlers.py` and provide the commands and container image.