"""Fast stream based import identification. Eventually this will likely replace parse.py """ from functools import partial from pathlib import Path from typing import Iterator, NamedTuple, Optional, TextIO, Tuple from isort.parse import _normalize_line, _strip_syntax, skip_line from .comments import parse as parse_comments from .settings import DEFAULT_CONFIG, Config STATEMENT_DECLARATIONS: Tuple[str, ...] = ("def ", "cdef ", "cpdef ", "class ", "@", "async def") class Import(NamedTuple): line_number: int indented: bool module: str attribute: Optional[str] = None alias: Optional[str] = None cimport: bool = False file_path: Optional[Path] = None def statement(self) -> str: import_cmd = "cimport" if self.cimport else "import" if self.attribute: import_string = f"from {self.module} {import_cmd} {self.attribute}" else: import_string = f"{import_cmd} {self.module}" if self.alias: import_string += f" as {self.alias}" return import_string def __str__(self) -> str: return ( f"{self.file_path or ''}:{self.line_number} " f"{'indented ' if self.indented else ''}{self.statement()}" ) def imports( input_stream: TextIO, config: Config = DEFAULT_CONFIG, file_path: Optional[Path] = None, top_only: bool = False, ) -> Iterator[Import]: """Parses a python file taking out and categorizing imports.""" in_quote = "" indexed_input = enumerate(input_stream) for index, raw_line in indexed_input: (skipping_line, in_quote) = skip_line( raw_line, in_quote=in_quote, index=index, section_comments=config.section_comments ) if top_only and not in_quote and raw_line.startswith(STATEMENT_DECLARATIONS): break if skipping_line: continue stripped_line = raw_line.strip().split("#")[0] if stripped_line.startswith("raise") or stripped_line.startswith("yield"): if stripped_line == "yield": while not stripped_line or stripped_line == "yield": try: index, next_line = next(indexed_input) except StopIteration: break stripped_line = next_line.strip().split("#")[0] while stripped_line.endswith("\\"): try: index, next_line = next(indexed_input) except StopIteration: break stripped_line = next_line.strip().split("#")[0] continue # pragma: no cover line, *end_of_line_comment = raw_line.split("#", 1) statements = [line.strip() for line in line.split(";")] if end_of_line_comment: statements[-1] = f"{statements[-1]}#{end_of_line_comment[0]}" for statement in statements: line, _raw_line = _normalize_line(statement) if line.startswith(("import ", "cimport ")): type_of_import = "straight" elif line.startswith("from "): type_of_import = "from" else: continue # pragma: no cover import_string, _ = parse_comments(line) normalized_import_string = ( import_string.replace("import(", "import (").replace("\\", " ").replace("\n", " ") ) cimports: bool = ( " cimport " in normalized_import_string or normalized_import_string.startswith("cimport") ) identified_import = partial( Import, index + 1, # line numbers use 1 based indexing raw_line.startswith((" ", "\t")), cimport=cimports, file_path=file_path, ) if "(" in line.split("#", 1)[0]: while not line.split("#")[0].strip().endswith(")"): try: index, next_line = next(indexed_input) except StopIteration: break line, _ = parse_comments(next_line) import_string += "\n" + line else: while line.strip().endswith("\\"): try: index, next_line = next(indexed_input) except StopIteration: break line, _ = parse_comments(next_line) # Still need to check for parentheses after an escaped line if "(" in line.split("#")[0] and ")" not in line.split("#")[0]: import_string += "\n" + line while not line.split("#")[0].strip().endswith(")"): try: index, next_line = next(indexed_input) except StopIteration: break line, _ = parse_comments(next_line) import_string += "\n" + line else: if import_string.strip().endswith( (" import", " cimport") ) or line.strip().startswith(("import ", "cimport ")): import_string += "\n" + line else: import_string = ( import_string.rstrip().rstrip("\\") + " " + line.lstrip() ) if type_of_import == "from": import_string = ( import_string.replace("import(", "import (") .replace("\\", " ") .replace("\n", " ") ) parts = import_string.split(" cimport " if cimports else " import ") from_import = parts[0].split(" ") import_string = (" cimport " if cimports else " import ").join( [from_import[0] + " " + "".join(from_import[1:])] + parts[1:] ) just_imports = [ item.replace("{|", "{ ").replace("|}", " }") for item in _strip_syntax(import_string).split() ] direct_imports = just_imports[1:] top_level_module = "" if "as" in just_imports and (just_imports.index("as") + 1) < len(just_imports): while "as" in just_imports: attribute = None as_index = just_imports.index("as") if type_of_import == "from": attribute = just_imports[as_index - 1] top_level_module = just_imports[0] module = top_level_module + "." + attribute alias = just_imports[as_index + 1] direct_imports.remove(attribute) direct_imports.remove(alias) direct_imports.remove("as") just_imports[1:] = direct_imports if attribute == alias and config.remove_redundant_aliases: yield identified_import(top_level_module, attribute) else: yield identified_import(top_level_module, attribute, alias=alias) else: module = just_imports[as_index - 1] alias = just_imports[as_index + 1] just_imports.remove(alias) just_imports.remove("as") just_imports.remove(module) if module == alias and config.remove_redundant_aliases: yield identified_import(module) else: yield identified_import(module, alias=alias) if just_imports: if type_of_import == "from": module = just_imports.pop(0) for attribute in just_imports: yield identified_import(module, attribute) else: for module in just_imports: yield identified_import(module)