wip: working, but requires testing

Got this to an initial working state, but now requires more eyes on it
and additional tests.

Author: yawpitch

.gitignore

@@ -0,0 +1,104 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+.hypothesis/
+.pytest_cache/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# pyenv
+.python-version
+
+# celery beat schedule file
+celerybeat-schedule
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/

Dockerfile

@@ -0,0 +1,11 @@
+FROM python:3.7-alpine
+
+RUN apk add --no-cache gcc libc-dev unixodbc-dev
+
+RUN mkdir /opt/representer
+COPY . /opt/representer
+WORKDIR /opt/representer
+
+RUN pip install -r requirements.txt
+
+ENTRYPOINT ["sh", "/opt/representer/bin/generate.sh"]

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2019 Michael Morehouse
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,8 @@
+# Exercism Python Representer
+
+An [automated anaylsis](analyis) tool that parses a Python file to create a normalized `representation.txt` file per the [representer interface][interface].
+
+ [analysis]: https://github.com/exercism/automated-analysis
+ [interface]: https://github.com/exercism/automated-analysis/blob/master/docs/representers/interface.md
+
+

bin/generate.py

@@ -0,0 +1,48 @@
+#! /usr/bin/env python3
+"""
+CLI for the representer for the Python track on Exercism.io.
+"""
+from argparse import ArgumentParser, ArgumentTypeError
+
+import representer
+
+
+def _slug(arg):
+    try:
+        return representer.utils.slug(arg)
+    except ValueError as err:
+        raise ArgumentTypeError(str(err))
+
+
+def _directory(arg):
+    try:
+        return representer.utils.directory(arg)
+    except (FileNotFoundError, PermissionError) as err:
+        raise ArgumentTypeError(str(err))
+
+
+def main():
+    """
+    Parse CLI arguments and create a representation.txt.
+    """
+    parser = ArgumentParser(
+        description="Produce a normalized representation of a Python exercise."
+    )
+
+    parser.add_argument(
+        "slug", metavar="SLUG", type=_slug, help="name of the exercise to process",
+    )
+
+    parser.add_argument(
+        "directory",
+        metavar="DIR",
+        type=_directory,
+        help="directory where the [EXERCISE.py] file is located",
+    )
+
+    args = parser.parse_args()
+    representer.represent(args.slug, args.directory)
+
+
+if __name__ == "__main__":
+    main()

bin/generate.sh

@@ -0,0 +1,5 @@
+#! /bin/sh
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+SRC="$( dirname "$DIR" )/src"
+export PYTHONPATH="$SRC:$PYTHONPATH"
+python bin/generate.py "$@"

requirements.txt

@@ -0,0 +1,2 @@
+astor==0.8.0
+black==19.10b0

src/representer/__init__.py

@@ -0,0 +1,78 @@
+"""
+Representer for Python.
+"""
+from typing import Dict
+
+from . import utils
+from .normalizer import Normalizer
+
+
+class Representer:
+    """
+    Represent Python code in normalized form.
+    """
+
+    def __init__(self, source: str) -> None:
+        self._tree = utils.parse(source)
+        self._normalizer = Normalizer()
+
+    def normalize(self) -> None:
+        """
+        Normalize the tree.
+        """
+        self._tree = self._normalizer.visit(self._tree)
+
+    def dump_tree(self) -> str:
+        """
+        Dump the current state of the tree for printing.
+        """
+        return utils.dump_tree(self._tree)
+
+    def dump_code(self, reformat=True) -> str:
+        """
+        Dump the current tree as generate code.
+        """
+        code = utils.to_source(self._tree)
+        if reformat:
+            return utils.reformat(code)
+        return code
+
+    @property
+    def mapping(self) -> Dict[str, str]:
+        """
+        Get the placeholder assignments after normalize.
+        """
+        return self._normalizer.get_placeholders()
+
+    def dump_map(self) -> str:
+        """
+        Dump the tree's mapping of placeholders.
+        """
+        return utils.to_json(self.mapping)
+
+
+def represent(slug: utils.Slug, directory: utils.Directory) -> None:
+    """
+    Normalize the `directory/slug.py` file representation.
+    """
+    src = directory.joinpath(slug.replace("-", "_") + ".py")
+    out_dst = directory.joinpath("representation.out")
+    txt_dst = directory.joinpath("representation.txt")
+    map_dst = directory.joinpath("mapping.json")
+
+    # parse the tree from the file contents
+    representation = Representer(src.read_text())
+
+    # save dump of the initial tree for debug
+    out = ["# BEGIN TREE BEFORE", representation.dump_tree(), ""]
+
+    # normalize the tree
+    representation.normalize()
+
+    # save dump of the normalized tree for debug
+    out.extend(["# BEGIN TREE AFTER", representation.dump_tree()])
+
+    # dump the representation files
+    out_dst.write_text("\n".join(out))
+    txt_dst.write_text(representation.dump_code())
+    map_dst.write_text(representation.dump_map())