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Diffstat (limited to 'Biz/Repl.py')
| -rw-r--r-- | Biz/Repl.py | 265 |
1 files changed, 0 insertions, 265 deletions
diff --git a/Biz/Repl.py b/Biz/Repl.py deleted file mode 100644 index 6b60d02..0000000 --- a/Biz/Repl.py +++ /dev/null @@ -1,265 +0,0 @@ -""" -Improve the standard Python REPL. - -This module attempts to emulate the workflow of ghci or lisp repls. It uses -importlib to load a namespace from the provided path, typechecks it with mypy, -and provides some tools for improving repl-driven development. - -This module is called in Biz/Ide/repl.sh like so: - - python -i Biz/Repl.py NS PATH - -where NS is the dot-partitioned namespace of the main module, and PATH is the -path to the same file. In the future this could be expanded to be a list of -additional files to load. -""" - -# : out python-improved-repl -# : dep mypy -import Biz.Log as Log -import importlib -import importlib.util -import inspect -import logging -import mypy.api -import os -import pathlib -import pydoc -import string -import subprocess -import sys -import textwrap -import types -import typing -import unittest - - -class ReplError(Exception): - """Type for errors at the repl.""" - - -def use(ns: str, path: str) -> None: - """ - Load or reload the module named 'ns' from 'path'. - - Like `use` in the Guile Scheme repl. - - Raises: - ReplError: if module cannot be loaded - """ - logging.info("loading %s from %s", ns, path) - spec = importlib.util.spec_from_file_location(ns, path) - if spec is None or spec.loader is None: - msg = f"spec could not be loaded for {ns} at {path}" - raise ReplError(msg) - module = importlib.util.module_from_spec(spec) - # delete module and its imported names if its already loaded - if ns in sys.modules: - del sys.modules[ns] - for name in module.__dict__: - if name in globals(): - del globals()[name] - sys.modules[ns] = module - spec.loader.exec_module(module) - names = list(module.__dict__) - globals().update({k: getattr(module, k) for k in names}) - - -def typecheck(path: str) -> None: - """Typecheck this namespace.""" - # this envvar is undocumented, but it works - # https://github.com/python/mypy/issues/13815 - os.environ["MYPY_FORCE_COLOR"] = "1" - logging.info("typechecking %s", path) - stdout, stderr, _ = mypy.api.run([path]) - sys.stdout.write(stdout) - sys.stdout.flush() - sys.stderr.write(stderr) - sys.stderr.flush() - - -def edit_file(ns: str, path: str, editor: str) -> None: - """ - Edit and reload the given namespace and path. - - It is assumed ns and path go together. If `editor` returns something other - than 0, this function will not reload the ns. - """ - try: - proc = subprocess.run([editor, path], check=False) - except FileNotFoundError: - logging.exception("editor '%s' not found", editor) - if proc.returncode == 0: - use(ns, path) - typecheck(path) - - -class CustomRepl: - """Custom repl commands, heavily inspired by ghci.""" - - def __init__(self, ns: str, path: str, editor: str) -> None: - """Create the custom repl for given ns and path.""" - self.ns = ns - self.path = path - self.editor = editor - self.default = sys.__excepthook__ - self.isframe = inspect.isframe - self.stack = inspect.stack - self.stdout = sys.stdout - self.whitespace = string.whitespace - - def setup(self) -> None: - """ - Load the NS, setup hooks and prompt. - - This basically does all the heavy lifting of customizing the Python - repl. - """ - # load given namespace - use(self.ns, self.path) - typecheck(self.path) - # setup hooks and prompt - sys.excepthook = self.excepthook - pydoc.pager = lambda text: pydoc.pipepager(text, "more") - sys.ps1 = f"{self.ns}> " - sys.ps2 = f"{self.ns}| " - - def help(self) -> str: - """Return help text.""" - return textwrap.dedent(f""" - repl commands: - :e open {self.ns} in {self.editor} - :r reload {self.ns} - :t obj show the type of obj - obj? expands to 'help(obj)' - :? show this help - """) - - def show_help(self) -> None: - """Print info about how to use this repl.""" - sys.stdout.write(self.help()) - sys.stdout.flush() - - def excepthook( - self, - type_: type[BaseException], - value: BaseException, - traceback: types.TracebackType | None, - ) -> typing.Any: - """ - Pre-process Python repl exceptions. - - This is called on `sys.excepthook`, which runs when the repl doesn't - know how to handle some input. So, we inspect `value` and provide - alternate functionality, bottoming out at the default exception. - - Raises: - ReplError: if caught exception is empty - """ - # ruff: noqa: PLR0911 - if not isinstance(value, SyntaxError): - return self.default(type_, value, traceback) - if value.text is None: - msg = f"value.text is None: {value}" - raise ReplError(msg) - stmt = value.text.rstrip() - if stmt == ":?": - self.show_help() - return None - if stmt.endswith("?"): - name = stmt.rstrip("?(" + self.whitespace) - self.get_help(name) - return None - if stmt == ":e": - self.edit() - return None - if stmt == ":r": - self.reload() - return None - if stmt.startswith(":t"): - var = stmt.split()[1] - self.get_type(var) - return None - return self.default(type_, value, traceback) - - def get_type(self, name: str) -> typing.Any | None: - """Return the type of `name` to the caller.""" - for record in self.stack(): - frame = record[0] - if not self.isframe(frame): - continue - cmd = f"typing.reveal_type({name})" - return eval(cmd, frame.f_globals, frame.f_locals) # noqa: S307 - return None - - def get_help(self, name: str) -> typing.Any | None: - """Return the documentation for `name` to the caller.""" - for record in self.stack(): - frame = record[0] - if not self.isframe(frame): - continue - cmd = f"help({name})" - return eval(cmd, frame.f_globals, frame.f_locals) # noqa: S307 - return None - - def reload(self) -> None: - """Reload the current namespace.""" - use(self.ns, self.path) - typecheck(self.path) - - def edit(self) -> None: - """Edit the current namespace.""" - edit_file(self.ns, self.path, self.editor) - - -class TestCustomRepl(unittest.TestCase): - """Test the CustomRepl functionality.""" - - def setUp(self) -> None: - """Create a CustomRepl for testing.""" - ns = __name__ - path = pathlib.Path(__name__.replace(".", "/")) - path = path.with_suffix(".py") - self.repl = CustomRepl(ns, str(path), "true") - self.repl.setup() - - def tearDown(self) -> None: - """Undo `self.setUp`.""" - sys.excepthook = self.repl.default - del self.repl - - def test_help(self) -> None: - """Help message should include the ns and path.""" - self.assertIn(self.repl.ns, self.repl.help()) - - -def test() -> None: - """Run this module's test suite.""" - suite = unittest.TestSuite() - suite.addTests( - unittest.defaultTestLoader.loadTestsFromTestCase(TestCustomRepl), - ) - unittest.TextTestRunner().run(suite) - - -def move() -> None: - """Actual entrypoint.""" - Log.setup() - ns = sys.argv[1] - path = sys.argv[2] - editor = os.environ.get("EDITOR", "$EDITOR") - repl = CustomRepl(ns, path, editor) - repl.setup() - repl.show_help() - - -def main() -> None: - """Entrypoint, should be replaced by a `Biz.Cli.main`.""" - if sys.argv[1] == "test": - test() - else: - move() - - -if __name__ == "__main__": - main() |