Issue 25180: Fix Tools/parser/unparse.py for f-strings. Patch by Martin Panter.

This commit is contained in:
Eric V. Smith 2015-09-20 15:09:15 -04:00
parent 57b6579315
commit 608adf9c82
2 changed files with 48 additions and 2 deletions

View File

@ -134,6 +134,15 @@ class ASTTestCase(unittest.TestCase):
class UnparseTestCase(ASTTestCase):
# Tests for specific bugs found in earlier versions of unparse
def test_fstrings(self):
# See issue 25180
self.check_roundtrip(r"""f'{f"{0}"*3}'""")
self.check_roundtrip(r"""f'{f"{y}"*3}'""")
self.check_roundtrip(r"""f'{f"{\'x\'}"*3}'""")
self.check_roundtrip(r'''f"{r'x' f'{\"s\"}'}"''')
self.check_roundtrip(r'''f"{r'x'rf'{\"s\"}'}"''')
def test_del_statement(self):
self.check_roundtrip("del x, y, z")
@ -264,8 +273,6 @@ class DirectoryTestCase(ASTTestCase):
for d in self.test_directories:
test_dir = os.path.join(basepath, d)
for n in os.listdir(test_dir):
if n == 'test_fstring.py':
continue
if n.endswith('.py') and not n.startswith('bad'):
names.append(os.path.join(test_dir, n))

View File

@ -322,6 +322,45 @@ class Unparser:
def _Str(self, tree):
self.write(repr(tree.s))
def _JoinedStr(self, t):
self.write("f")
string = io.StringIO()
self._fstring_JoinedStr(t, string.write)
self.write(repr(string.getvalue()))
def _FormattedValue(self, t):
self.write("f")
string = io.StringIO()
self._fstring_FormattedValue(t, string.write)
self.write(repr(string.getvalue()))
def _fstring_JoinedStr(self, t, write):
for value in t.values:
meth = getattr(self, "_fstring_" + type(value).__name__)
meth(value, write)
def _fstring_Str(self, t, write):
value = t.s.replace("{", "{{").replace("}", "}}")
write(value)
def _fstring_FormattedValue(self, t, write):
write("{")
expr = io.StringIO()
Unparser(t.value, expr)
expr = expr.getvalue().rstrip("\n")
if expr.startswith("{"):
write(" ") # Separate pair of opening brackets as "{ {"
write(expr)
if t.conversion != -1:
conversion = chr(t.conversion)
assert conversion in "sra"
write(f"!{conversion}")
if t.format_spec:
write(":")
meth = getattr(self, "_fstring_" + type(t.format_spec).__name__)
meth(t.format_spec, write)
write("}")
def _Name(self, t):
self.write(t.id)