Improve get_future_imports implementation.

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index 7e39c92009d2aefcf3b2910f9dce1fcca8b2cbe2..36a180da702a3a003276dc3a8e1f25b96b4abd01 100644 (file)
--- a/black.py
+++ b/black.py
@@ -20,6 +20,7 @@ from typing import (
     Callable,
     Collection,
     Dict,
+    Generator,
     Generic,
     Iterable,
     Iterator,
@@ -46,7 +47,7 @@ from blib2to3.pgen2 import driver, token
 from blib2to3.pgen2.parse import ParseError
 
 
-__version__ = "18.6b2"
+__version__ = "18.6b4"
 DEFAULT_LINE_LENGTH = 88
 DEFAULT_EXCLUDES = (
     r"/(\.git|\.hg|\.mypy_cache|\.tox|\.venv|_build|buck-out|build|dist)/"
@@ -2577,6 +2578,9 @@ def convert_one_fmt_off_pair(node: Node) -> bool:
                         continue
 
                 ignored_nodes = list(generate_ignored_nodes(leaf))
+                if not ignored_nodes:
+                    continue
+
                 first = ignored_nodes[0]  # Can be a container node with the `leaf`.
                 parent = first.parent
                 prefix = first.prefix
@@ -2605,7 +2609,7 @@ def convert_one_fmt_off_pair(node: Node) -> bool:
                 )
                 return True
 
-            previous_consumed += comment.consumed
+            previous_consumed = comment.consumed
 
     return False
 
@@ -2907,7 +2911,23 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[Leaf
 
 def get_future_imports(node: Node) -> Set[str]:
     """Return a set of __future__ imports in the file."""
-    imports = set()
+    imports: Set[str] = set()
+
+    def get_imports_from_children(children: List[LN]) -> Generator[str, None, None]:
+        for child in children:
+            if isinstance(child, Leaf):
+                if child.type == token.NAME:
+                    yield child.value
+            elif child.type == syms.import_as_name:
+                orig_name = child.children[0]
+                assert isinstance(orig_name, Leaf), "Invalid syntax parsing imports"
+                assert orig_name.type == token.NAME, "Invalid syntax parsing imports"
+                yield orig_name.value
+            elif child.type == syms.import_as_names:
+                yield from get_imports_from_children(child.children)
+            else:
+                assert False, "Invalid syntax parsing imports"
+
     for child in node.children:
         if child.type != syms.simple_stmt:
             break
@@ -2926,15 +2946,7 @@ def get_future_imports(node: Node) -> Set[str]:
             module_name = first_child.children[1]
             if not isinstance(module_name, Leaf) or module_name.value != "__future__":
                 break
-            for import_from_child in first_child.children[3:]:
-                if isinstance(import_from_child, Leaf):
-                    if import_from_child.type == token.NAME:
-                        imports.add(import_from_child.value)
-                else:
-                    assert import_from_child.type == syms.import_as_names
-                    for leaf in import_from_child.children:
-                        if isinstance(leaf, Leaf) and leaf.type == token.NAME:
-                            imports.add(leaf.value)
+            imports |= set(get_imports_from_children(first_child.children[3:]))
         else:
             break
     return imports
@@ -2950,7 +2962,7 @@ def gen_python_files_in_dir(
     """Generate all files under `path` whose paths are not excluded by the
     `exclude` regex, but are included by the `include` regex.
 
-    Symbolic links pointing outside of the root directory are ignored.
+    Symbolic links pointing outside of the `root` directory are ignored.
 
     `report` is where output about exclusions goes.
     """
@@ -2961,8 +2973,7 @@ def gen_python_files_in_dir(
         except ValueError:
             if child.is_symlink():
                 report.path_ignored(
-                    child,
-                    "is a symbolic link that points outside of the root directory",
+                    child, f"is a symbolic link that points outside {root}"
                 )
                 continue
 
@@ -3482,5 +3493,28 @@ def write_cache(
         pass
 
 
+def patch_click() -> None:
+    """Make Click not crash.
+
+    On certain misconfigured environments, Python 3 selects the ASCII encoding as the
+    default which restricts paths that it can access during the lifetime of the
+    application.  Click refuses to work in this scenario by raising a RuntimeError.
+
+    In case of Black the likelihood that non-ASCII characters are going to be used in
+    file paths is minimal since it's Python source code.  Moreover, this crash was
+    spurious on Python 3.7 thanks to PEP 538 and PEP 540.
+    """
+    try:
+        from click import core
+        from click import _unicodefun  # type: ignore
+    except ModuleNotFoundError:
+        return
+
+    for module in (core, _unicodefun):
+        if hasattr(module, "_verify_python3_env"):
+            module._verify_python3_env = lambda: None
+
+
 if __name__ == "__main__":
+    patch_click()
     main()