| """Fixer for import statements. |
| If spam is being imported from the local directory, this import: |
| from spam import eggs |
| Becomes: |
| from .spam import eggs |
| |
| And this import: |
| import spam |
| Becomes: |
| from . import spam |
| """ |
| |
| # Local imports |
| from .. import fixer_base |
| from os.path import dirname, join, exists, sep |
| from ..fixer_util import FromImport, syms, token |
| |
| |
| def traverse_imports(names): |
| """ |
| Walks over all the names imported in a dotted_as_names node. |
| """ |
| pending = [names] |
| while pending: |
| node = pending.pop() |
| if node.type == token.NAME: |
| yield node.value |
| elif node.type == syms.dotted_name: |
| yield "".join([ch.value for ch in node.children]) |
| elif node.type == syms.dotted_as_name: |
| pending.append(node.children[0]) |
| elif node.type == syms.dotted_as_names: |
| pending.extend(node.children[::-2]) |
| else: |
| raise AssertionError("unkown node type") |
| |
| |
| class FixImport(fixer_base.BaseFix): |
| BM_compatible = True |
| |
| PATTERN = """ |
| import_from< 'from' imp=any 'import' ['('] any [')'] > |
| | |
| import_name< 'import' imp=any > |
| """ |
| |
| def start_tree(self, tree, name): |
| super(FixImport, self).start_tree(tree, name) |
| self.skip = "absolute_import" in tree.future_features |
| |
| def transform(self, node, results): |
| if self.skip: |
| return |
| imp = results['imp'] |
| |
| if node.type == syms.import_from: |
| # Some imps are top-level (eg: 'import ham') |
| # some are first level (eg: 'import ham.eggs') |
| # some are third level (eg: 'import ham.eggs as spam') |
| # Hence, the loop |
| while not hasattr(imp, 'value'): |
| imp = imp.children[0] |
| if self.probably_a_local_import(imp.value): |
| imp.value = u"." + imp.value |
| imp.changed() |
| else: |
| have_local = False |
| have_absolute = False |
| for mod_name in traverse_imports(imp): |
| if self.probably_a_local_import(mod_name): |
| have_local = True |
| else: |
| have_absolute = True |
| if have_absolute: |
| if have_local: |
| # We won't handle both sibling and absolute imports in the |
| # same statement at the moment. |
| self.warning(node, "absolute and local imports together") |
| return |
| |
| new = FromImport(u".", [imp]) |
| new.prefix = node.prefix |
| return new |
| |
| def probably_a_local_import(self, imp_name): |
| if imp_name.startswith(u"."): |
| # Relative imports are certainly not local imports. |
| return False |
| imp_name = imp_name.split(u".", 1)[0] |
| base_path = dirname(self.filename) |
| base_path = join(base_path, imp_name) |
| # If there is no __init__.py next to the file its not in a package |
| # so can't be a relative import. |
| if not exists(join(dirname(base_path), "__init__.py")): |
| return False |
| for ext in [".py", sep, ".pyc", ".so", ".sl", ".pyd"]: |
| if exists(base_path + ext): |
| return True |
| return False |
