codeql/rust/README.md

# Rust on CodeQL

## Development

### Dependencies

If you don't have the `semmle-code` repo you may need to install Bazel manually, e.g. from https://github.com/bazelbuild/bazelisk.

### Building the Rust Extractor

This approach uses a released `codeql` version and is simpler to use for QL development. From anywhere under your `semmle-code` or `codeql` directory you can run:
```bash
bazel run @codeql//rust:install
```

You can use shorter versions of the above command:
```bash
bazel run //rust:install  # if under the `codeql` checkout
bazel run rust:install  # if at the root of the `codeql` checkout
bazel run :install  # if at the `rust` directory of the `codeql` checkout
```

You now need to create a [per-user CodeQL configuration file](https://docs.github.com/en/code-security/codeql-cli/using-the-advanced-functionality-of-the-codeql-cli/specifying-command-options-in-a-codeql-configuration-file#using-a-codeql-configuration-file) and specify the option:
```
--search-path PATH/TO/semmle-code/ql
```
(wherever the `codeql` checkout is on your system)

You can now use the Rust extractor e.g. to run Rust tests from the command line or in VSCode.

### Building the Rust Extractor (as a sembuild target)

This approach allows you to build a Rust extractor with a CLI built from source. From your `semmle-code` directory run:
```bash
./build target/intree/codeql-rust
```
You can now invoke it directly, for example to run some tests:
```bash
./target/intree/codeql-rust/codeql test run ql/rust/ql/test/PATH/TO/TEST/
```

### Building a Database

TODO

### Code Generation

If you make changes to either
* `ast-generator/`, or
* `schema/*.py`

you'll need to regenerate code. You can do so running
```sh
bazel run @codeql//rust/codegen
```

Sometimes, especially if resolving conflicts on generated files, you might need to run
```sh
bazel run @codeql//rust/codegen -- --force
```
for code generation to succeed.