Telethon/telethon_generator/parser/source_builder.py
2018-04-01 12:46:44 +02:00

66 lines
2.1 KiB
Python

class SourceBuilder:
"""This class should be used to build .py source files"""
def __init__(self, out_stream, indent_size=4):
self.current_indent = 0
self.on_new_line = False
self.indent_size = indent_size
self.out_stream = out_stream
# Was a new line added automatically before? If so, avoid it
self.auto_added_line = False
def indent(self):
"""Indents the current source code line
by the current indentation level
"""
self.write(' ' * (self.current_indent * self.indent_size))
def write(self, string, *args, **kwargs):
"""Writes a string into the source code,
applying indentation if required
"""
if self.on_new_line:
self.on_new_line = False # We're not on a new line anymore
# If the string was not empty, indent; Else probably a new line
if string.strip():
self.indent()
if args or kwargs:
self.out_stream.write(string.format(*args, **kwargs))
else:
self.out_stream.write(string)
def writeln(self, string='', *args, **kwargs):
"""Writes a string into the source code _and_ appends a new line,
applying indentation if required
"""
self.write(string + '\n', *args, **kwargs)
self.on_new_line = True
# If we're writing a block, increment indent for the next time
if string and string[-1] == ':':
self.current_indent += 1
# Clear state after the user adds a new line
self.auto_added_line = False
def end_block(self):
"""Ends an indentation block, leaving an empty line afterwards"""
self.current_indent -= 1
# If we did not add a new line automatically yet, now it's the time!
if not self.auto_added_line:
self.writeln()
self.auto_added_line = True
def __str__(self):
self.out_stream.seek(0)
return self.out_stream.read()
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self.out_stream.close()