示例#1
0
    def get_doctests(self):
        r"""
        Return doctests in this code.

          >>> PythonBlock("x\n'''\n >>> foo(bar\n ...     + baz)\n'''\n").get_doctests()
          [PythonBlock('foo(bar\n    + baz)\n', startpos=(3,2))]

        :rtype:
          ``list`` of `PythonStatement` s
        """
        import doctest
        parser = doctest.DocTestParser()
        doctest_blocks = []
        filename = self.filename
        flags = self.flags
        for ast_node in self._get_docstring_nodes():
            try:
                examples = parser.get_examples(ast_node.s)
            except Exception:
                blob = ast_node.s
                if len(blob) > 60:
                    blob = blob[:60] + '...'
                # TODO: let caller decide how to handle
                logger.warning("Can't parse docstring; ignoring: %r", blob)
                continue
            for example in examples:
                lineno = ast_node.startpos.lineno + example.lineno
                colno = ast_node.startpos.colno + example.indent  # dubious
                text = FileText(example.source,
                                filename=filename,
                                startpos=(lineno, colno))
                try:
                    block = PythonBlock(text, flags=flags)
                    block.ast_node  # make sure we can parse
                except Exception:
                    blob = text.joined
                    if len(blob) > 60:
                        blob = blob[:60] + '...'
                    logger.warning("Can't parse doctest; ignoring: %r", blob)
                    continue
                doctest_blocks.append(block)
        return doctest_blocks
示例#2
0
def _get_python_path(env_var_name, default_path, target_dirname):
    '''
    Expand an environment variable specifying pyflyby input config files.

      - Default to C{default_path} if the environment variable is undefined.
      - Process colon delimiters.
      - Replace "-" with C{default_path}.
      - Expand triple dots.
      - Recursively traverse directories.

    @rtype:
      C{tuple} of C{Filename}s
    '''
    pathnames = _get_env_var(env_var_name, default_path)
    if pathnames == ["EMPTY"]:
        # The special code PYFLYBY_PATH=EMPTY means we intentionally want to
        # use an empty PYFLYBY_PATH (and don't fall back to the default path,
        # nor warn about an empty path).
        return ()
    for p in pathnames:
        if re.match("/|[.]/|[.][.][.]/|~/", p):
            continue
        raise ValueError(
            "{env_var_name} components should start with / or ./ or ~/ or .../.  "
            "Use {env_var_name}=./{p} instead of {env_var_name}={p} if you really "
            "want to use the current directory.".format(
                env_var_name=env_var_name, p=p))
    pathnames = [os.path.expanduser(p) for p in pathnames]
    pathnames = _expand_tripledots(pathnames, target_dirname)
    pathnames = [Filename(fn) for fn in pathnames]
    pathnames = stable_unique(pathnames)
    pathnames = expand_py_files_from_args(pathnames)
    if not pathnames:
        logger.warning(
            "No import libraries found (%s=%r, default=%r)" %
            (env_var_name, os.environ.get(env_var_name), default_path))
    return tuple(pathnames)
示例#3
0
def replace_star_imports(codeblock, params=None):
    r"""
    Replace lines such as::
      from foo.bar import *
    with
      from foo.bar import f1, f2, f3

    Note that this requires involves actually importing C{foo.bar}, which may
    have side effects.  (TODO: rewrite to avoid this?)

    The result includes all imports from the C{email} module.  The result
    excludes shadowed imports.  In this example:
      1. The original C{MIMEAudio} import is shadowed, so it is removed.
      2. The C{MIMEImage} import in the C{email} module is shadowed by a
         subsequent import, so it is omitted.

      >>> codeblock = PythonBlock('from keyword import *', filename="/tmp/x.py")

      >>> print replace_star_imports(codeblock)
      [PYFLYBY] /tmp/x.py: replaced 'from keyword import *' with 2 imports
      from keyword import iskeyword, kwlist
      <BLANKLINE>

    Usually you'll want to remove unused imports after replacing star imports.

    @type codeblock:
      L{PythonBlock} or convertible (C{str})
    @rtype:
      L{PythonBlock}
    """
    from pyflyby._modules import ModuleHandle
    params = ImportFormatParams(params)
    codeblock = PythonBlock(codeblock)
    filename = codeblock.filename
    transformer = SourceToSourceFileImportsTransformation(codeblock)
    for block in transformer.import_blocks:
        # Iterate over the import statements in C{block.input}.  We do this
        # instead of using C{block.importset} because the latter doesn't
        # preserve the order of inputs.  The order is important for
        # determining what's shadowed.
        imports = [
            imp for s in block.input.statements
            for imp in ImportStatement(s).imports
        ]
        # Process "from ... import *" statements.
        new_imports = []
        for imp in imports:
            if imp.split.member_name != "*":
                new_imports.append(imp)
            elif imp.split.module_name.startswith("."):
                # The source contains e.g. "from .foo import *".  Right now we
                # don't have a good way to figure out the absolute module
                # name, so we can't get at foo.  That said, there's a decent
                # chance that this is inside an __init__ anyway, which is one
                # of the few justifiable use cases for star imports in library
                # code.
                logger.warning(
                    "%s: can't replace star imports in relative import: %s",
                    filename,
                    imp.pretty_print().strip())
                new_imports.append(imp)
            else:
                module = ModuleHandle(imp.split.module_name)
                try:
                    with ImportPathForRelativeImportsCtx(codeblock):
                        exports = module.exports
                except Exception as e:
                    logger.warning(
                        "%s: couldn't import '%s' to enumerate exports, "
                        "leaving unchanged: '%s'.  %s: %s", filename,
                        module.name, imp,
                        type(e).__name__, e)
                    new_imports.append(imp)
                    continue
                if not exports:
                    # We found nothing in the target module.  This probably
                    # means that module itself is just importing things from
                    # other modules.  Currently we intentionally exclude those
                    # imports since usually we don't want them.  TODO: do
                    # something better here.
                    logger.warning("%s: found nothing to import from %s, ",
                                   "leaving unchanged: '%s'", filename, module,
                                   imp)
                    new_imports.append(imp)
                else:
                    new_imports.extend(exports)
                    logger.info("%s: replaced %r with %d imports", filename,
                                imp.pretty_print().strip(), len(exports))
        block.importset = ImportSet(new_imports, ignore_shadowed=True)
    return transformer.output(params=params)
示例#4
0
def fix_unused_and_missing_imports(codeblock,
                                   add_missing=True,
                                   remove_unused="AUTOMATIC",
                                   add_mandatory=True,
                                   db=None,
                                   params=None):
    r"""
    Check for unused and missing imports, and fix them automatically.

    Also formats imports.

    In the example below, C{m1} and C{m3} are unused, so are automatically
    removed.  C{np} was undefined, so an C{import numpy as np} was
    automatically added.

      >>> codeblock = PythonBlock(
      ...     'from foo import m1, m2, m3, m4\n'
      ...     'm2, m4, np.foo', filename="/tmp/foo.py")

      >>> print fix_unused_and_missing_imports(codeblock, add_mandatory=False)
      [PYFLYBY] /tmp/foo.py: removed unused 'from foo import m1'
      [PYFLYBY] /tmp/foo.py: removed unused 'from foo import m3'
      [PYFLYBY] /tmp/foo.py: added 'import numpy as np'
      import numpy as np
      from foo import m2, m4
      m2, m4, np.foo

    @type codeblock:
      L{PythonBlock} or convertible (C{str})
    @rtype:
      L{PythonBlock}
    """
    codeblock = PythonBlock(codeblock)
    if remove_unused == "AUTOMATIC":
        fn = codeblock.filename
        remove_unused = not (fn and (fn.base == "__init__.py"
                                     or ".pyflyby" in str(fn).split("/")))
    elif remove_unused is True or remove_unused is False:
        pass
    else:
        raise ValueError("Invalid remove_unused=%r" % (remove_unused, ))
    params = ImportFormatParams(params)
    db = ImportDB.interpret_arg(db, target_filename=codeblock.filename)
    # Do a first pass reformatting the imports to get rid of repeated or
    # shadowed imports, e.g. L1 here:
    #   import foo  # L1
    #   import foo  # L2
    #   foo         # L3
    codeblock = reformat_import_statements(codeblock, params=params)

    filename = codeblock.filename
    transformer = SourceToSourceFileImportsTransformation(codeblock)
    missing_imports, unused_imports = scan_for_import_issues(
        codeblock, find_unused_imports=remove_unused, parse_docstrings=True)
    logger.debug("missing_imports = %r", missing_imports)
    logger.debug("unused_imports = %r", unused_imports)
    if remove_unused and unused_imports:
        # Go through imports to remove.  [This used to be organized by going
        # through import blocks and removing all relevant blocks from there,
        # but if one removal caused problems the whole thing would fail.  The
        # CPU cost of calling without_imports() multiple times isn't worth
        # that.]
        # TODO: don't remove unused mandatory imports.  [This isn't
        # implemented yet because this isn't necessary for __future__ imports
        # since they aren't reported as unused, and those are the only ones we
        # have by default right now.]
        for lineno, imp in unused_imports:
            try:
                imp = transformer.remove_import(imp, lineno)
            except NoSuchImportError:
                logger.error(
                    "%s: couldn't remove import %r",
                    filename,
                    imp,
                )
            except LineNumberNotFoundError as e:
                logger.error("%s: unused import %r on line %d not global",
                             filename, str(imp), e.args[0])
            else:
                logger.info("%s: removed unused '%s'", filename, imp)

    if add_missing and missing_imports:
        missing_imports.sort(key=lambda k: (k[1], k[0]))
        known = db.known_imports.by_import_as
        # Decide on where to put each import to be added.  Find the import
        # block with the longest common prefix.  Tie-break by preferring later
        # blocks.
        added_imports = set()
        for lineno, ident in missing_imports:
            import_as = ident.parts[0]
            try:
                imports = known[import_as]
            except KeyError:
                logger.warning(
                    "%s:%s: undefined name %r and no known import for it",
                    filename, lineno, import_as)
                continue
            if len(imports) != 1:
                logger.error("%s: don't know which of %r to use", filename,
                             imports)
                continue
            imp_to_add = imports[0]
            if imp_to_add in added_imports:
                continue
            transformer.add_import(imp_to_add, lineno)
            added_imports.add(imp_to_add)
            logger.info("%s: added %r", filename,
                        imp_to_add.pretty_print().strip())

    if add_mandatory:
        # Todo: allow not adding to empty __init__ files?
        mandatory = db.mandatory_imports.imports
        for imp in mandatory:
            try:
                transformer.add_import(imp)
            except ImportAlreadyExistsError:
                pass
            else:
                logger.info("%s: added mandatory %r", filename,
                            imp.pretty_print().strip())

    return transformer.output(params=params)