pytest-ast-transformer 1.0.3

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[](https://travis-ci.org/okorolev/pytest-ast-transformer)
[](https://pypi.org/project/pytest-ast-transformer/)

## About
AST Transformer integrated with py.test.

Useful for debug, refactoring, 'clean asserts' (see [examples/replace_asserts](examples/replace_asserts))

Support options
---------------
| Options | Description |
| ----------- | ----------- |
| `--show-code` | show generated code |
| `--disable-transforms` | disable all ast transformers |

## Install
```bash
pip install pytest-ast-transformer
```

## Usage

* Write ast transformer
```python
# transformer.py
import ast

from pytest_ast_transformer.ast_transformer import PytestTransformer


def my_assert(test_result, msg=''):
print(f'my assert: {test_result} {msg}')
assert test_result, msg


class AssertTransformer(PytestTransformer):
context = {
'my_assert': my_assert
}

def visit_Assert(self, node: ast.Assert) -> ast.Expr:
func_name = ast.Name(id='my_assert', ctx=ast.Load())
call_func = ast.Call(func=func_name, args=[node.test, node.msg], keywords=[])
expr = ast.Expr(value=call_func)

return ast.fix_missing_locations(expr)
```
* Register new ast transformer
```python
# conftest.py
from pytest_ast_transformer.ast_manager import ASTManager
from tests.transformer import AssertTransformer


def pytest_register_ast_transformer(ast_manager: ASTManager):
ast_manager.add_transformer(AssertTransformer())
```