Files
codeql/swift/codegen/lib/render.py
2022-06-23 14:22:58 +02:00

54 lines
1.9 KiB
Python

""" template renderer module, wrapping around `pystache.Renderer`
`pystache` is a python mustache engine, and mustache is a template language. More information on
https://mustache.github.io/
"""
import logging
import pathlib
import pystache
from . import paths
log = logging.getLogger(__name__)
class Renderer:
""" Template renderer using mustache templates in the `templates` directory """
def __init__(self, generator):
self._r = pystache.Renderer(search_dirs=str(paths.templates_dir), escape=lambda u: u)
self.written = set()
self._generator = generator
def render(self, data, output: pathlib.Path):
""" Render `data` to `output`.
`data` must have a `template` attribute denoting which template to use from the template directory.
Optionally, `data` can also have an `extensions` attribute denoting list of file extensions: they will all be
appended to the template name with an underscore and be generated in turn.
"""
mnemonic = type(data).__name__
output.parent.mkdir(parents=True, exist_ok=True)
extensions = getattr(data, "extensions", [None])
for ext in extensions:
output_filename = output
template = data.template
if ext:
output_filename = output_filename.with_suffix(f".{ext}")
template += f"_{ext}"
contents = self._r.render_name(template, data, generator=self._generator)
with open(output_filename, "w") as out:
out.write(contents)
log.debug(f"{mnemonic}: generated {output.name}")
self.written.add(output_filename)
def cleanup(self, existing):
""" Remove files in `existing` for which no `render` has been called """
for f in existing - self.written:
f.unlink(missing_ok=True)
log.info(f"removed {f.name}")