diff options
| -rw-r--r-- | lib/spack/external/spack_astunparse/__init__.py | 4 | ||||
| -rw-r--r-- | lib/spack/external/spack_astunparse/unparser.py | 80 |
2 files changed, 71 insertions, 13 deletions
diff --git a/lib/spack/external/spack_astunparse/__init__.py b/lib/spack/external/spack_astunparse/__init__.py index 0d48b4df7a..33c44b7812 100644 --- a/lib/spack/external/spack_astunparse/__init__.py +++ b/lib/spack/external/spack_astunparse/__init__.py @@ -7,7 +7,7 @@ from .unparser import Unparser __version__ = '1.6.3' -def unparse(tree): +def unparse(tree, py_ver_consistent=False): v = cStringIO() - Unparser(tree, file=v) + Unparser(tree, file=v, py_ver_consistent=py_ver_consistent) return v.getvalue() diff --git a/lib/spack/external/spack_astunparse/unparser.py b/lib/spack/external/spack_astunparse/unparser.py index 0ef6fd8bcb..854af9a534 100644 --- a/lib/spack/external/spack_astunparse/unparser.py +++ b/lib/spack/external/spack_astunparse/unparser.py @@ -29,12 +29,39 @@ class Unparser: output source code for the abstract syntax; original formatting is disregarded. """ - def __init__(self, tree, file = sys.stdout): + def __init__(self, tree, file = sys.stdout, py_ver_consistent=False): """Unparser(tree, file=sys.stdout) -> None. - Print the source for tree to file.""" + Print the source for tree to file. + + Arguments: + py_ver_consistent (bool): if True, generate unparsed code that is + consistent between Python 2.7 and 3.5-3.10. + + Consistency is achieved by: + 1. Ensuring there are no spaces between unary operators and + their operands. + 2. Ensuring that *args and **kwargs are always the last arguments, + regardless of the python version. + 3. Always unparsing print as a function. + 4. Not putting an extra comma after Python 2 class definitions. + + Without these changes, the same source can generate different code for different + Python versions, depending on subtle AST differences. + + One place where single source will generate an inconsistent AST is with + multi-argument print statements, e.g.:: + + print("foo", "bar", "baz") + + In Python 2, this prints a tuple; in Python 3, it is the print function with + multiple arguments. Use ``from __future__ import print_function`` to avoid + this inconsistency. + + """ self.f = file self.future_imports = [] self._indent = 0 + self._py_ver_consistent = py_ver_consistent self.dispatch(tree) print("", file=self.f) self.f.flush() @@ -175,7 +202,12 @@ class Unparser: self.dispatch(t.locals) def _Print(self, t): - self.fill("print ") + # Use print function so that python 2 unparsing is consistent with 3 + if self._py_ver_consistent: + self.fill("print(") + else: + self.fill("print ") + do_comma = False if t.dest: self.write(">>") @@ -188,6 +220,9 @@ class Unparser: if not t.nl: self.write(",") + if self._py_ver_consistent: + self.write(")") + def _Global(self, t): self.fill("global ") interleave(lambda: self.write(", "), self.write, t.names) @@ -335,9 +370,10 @@ class Unparser: self.write(")") elif t.bases: self.write("(") - for a in t.bases: + for a in t.bases[:-1]: self.dispatch(a) self.write(", ") + self.dispatch(t.bases[-1]) self.write(")") self.enter() self.dispatch(t.body) @@ -662,7 +698,8 @@ class Unparser: def _UnaryOp(self, t): self.write("(") self.write(self.unop[t.op.__class__.__name__]) - self.write(" ") + if not self._py_ver_consistent: + self.write(" ") if six.PY2 and isinstance(t.op, ast.USub) and isinstance(t.operand, ast.Num): # If we're applying unary minus to a number, parenthesize the number. # This is necessary: -2147483648 is different from -(2147483648) on @@ -717,14 +754,34 @@ class Unparser: self.dispatch(t.func) self.write("(") comma = False + + # move starred arguments last in Python 3.5+, for consistency w/earlier versions + star_and_kwargs = [] + move_stars_last = sys.version_info[:2] >= (3, 5) + for e in t.args: - if comma: self.write(", ") - else: comma = True - self.dispatch(e) + if move_stars_last and isinstance(e, ast.Starred): + star_and_kwargs.append(e) + else: + if comma: self.write(", ") + else: comma = True + self.dispatch(e) + for e in t.keywords: - if comma: self.write(", ") - else: comma = True - self.dispatch(e) + # starting from Python 3.5 this denotes a kwargs part of the invocation + if e.arg is None and move_stars_last: + star_and_kwargs.append(e) + else: + if comma: self.write(", ") + else: comma = True + self.dispatch(e) + + if move_stars_last: + for e in star_and_kwargs: + if comma: self.write(", ") + else: comma = True + self.dispatch(e) + if sys.version_info[:2] < (3, 5): if t.starargs: if comma: self.write(", ") @@ -736,6 +793,7 @@ class Unparser: else: comma = True self.write("**") self.dispatch(t.kwargs) + self.write(")") def _Subscript(self, t): |