def test_variable_formatting():
value = 12.35
width = 10
precision=2
# Needs the trailing }f on 2.7
assert str(f('result: {value:{width}.{precision}f}')) == 'result: 12.35'
assert str(f('result: {value:{width!r}.{precision}f}')) == 'result: 12.35'
assert str(f('result: {value:{width:0}.{precision:1}f}')) == 'result: 12.35'
def test_constant():
assert str(f('{{{10}')) == '{10'
assert str(f('}}{10}')) == '}10'
assert str(f('}}{{{10}')) == '}{10'
assert str(f('}}a{{{10}')) == '}a{10'
assert str(f('{10}{{')) == '10{'
assert str(f('{10}}}')) == '10}'
assert str(f('{10}}}{{')) == '10}{'
assert str(f('{10}}}a{{'))+ '}' == '10}a{}'
def test_lookups():
a = 0
d = {"#":"hash",0:'integer',"a":"string","'":"squote","foo":"bar"}
assert str(f('{"#"}')) == '#'
assert str(f('{d["#"]}')) == 'hash'
assert str(f('{d[0]}')) == 'integer'
assert str(f('{d["a"]}')) == 'string'
assert str(f('''{d["'"]}''')) == 'squote'
assert str(f('{d["foo"]}')) == 'bar'
# This one does not pass because it's not really 3.6
with pytest.raises(AssertionError):
assert str(f('{d[a]}')) == 'integer'
assert str(f('{d[a]}')) == 'string'
def test_complex_eval():
assert str(f('{3,}')) == '(3,)'
assert "module 'string' from" in str(f('{string}'))
assert str(f('g:{a_global}')) == 'g:really a local'
assert str(f('g:{a_global!r}')) == "g:'really a local'"
assert str(f('{[x for x in range(5)]}')) == '[0, 1, 2, 3, 4]'
assert str(f('{3.14:!<10.10}')) == '3.14!!!!!!'
def examples_from_python():
class Extra(object):
def __init__(self):
self._waiters = [1, 2]
def test(self, extra):
extra1 = '{},waiters:{}'.format(extra, len(self._waiters))
extra2 = str(f('{extra},waiters:{len(self._waiters)}'))
assert extra1 == extra2
e = Extra()
e.test("x")
lineno = 123
m1 = " [line {0:2d}]".format(lineno)
m2 = str(f(" [line {lineno:2d}]"))
assert m1 == m2
c_basename = "some_class_name"
m1 = methoddef_name = "{}_METHODDEF".format(c_basename.upper())
m2 = methoddef_name = str(f("{c_basename.upper()}_METHODDEF"))
assert m1 == m2
class Sys(object):
def __init__(self, *args):
self.argv = list(args)
xsys = Sys("someprogram.py", "arg0")
valid_opts = ["option"]
print "Usage: {0} [{1}]".format(xsys.argv[0],
'|'.join('--' + opt for opt in valid_opts))
print f(
"Usage: {xsys.argv[0]} [{'|'.join('--'+opt for opt in valid_opts)}]")
printf(
"Usage: {xsys.argv[0]} [{'|'.join('--'+opt for opt in valid_opts)}]")
printf("Usage: {xsys.argv[0]} [{opts}]",
opts='|'.join('--' + opt for opt in valid_opts))
for i in range(10):
s = str(f("{i*10}"))
def test_concat():
x = 'def'
assert 'abc' + str(f('## {x}ghi')) == 'abc## defghi'
def test_braces():
assert str(f('{"{{}}"}')) == '{{}}'
def test_simple():
y="class"
assert str(f('{y}')) == format(y)
assert str(f('{y}')) == 'class'
assert str(f('{{')) == '{'
assert str(f('a{{')) == 'a{'
assert str(f('{{b')) == '{b'
assert str(f('a{{b')) == 'a{b'
assert str(f('}}')) == '}'
assert str(f('a}}')) == 'a}'
assert str(f('}}b')) == '}b'
assert str(f('a}}b')) == 'a}b'
assert str(f('{{}}')) == '{}'
assert str(f('a{{}}')) == 'a{}'
assert str(f('{{b}}')) == '{b}'
assert str(f('{{}}c')) == '{}c'
assert str(f('a{{b}}')) == 'a{b}'
assert str(f('a{{}}c')) == 'a{}c'
assert str(f('{{b}}c')) == '{b}c'
assert str(f('a{{b}}c')) == 'a{b}c'
def test(self, extra):
extra1 = '{},waiters:{}'.format(extra, len(self._waiters))
extra2 = str(f('{extra},waiters:{len(self._waiters)}'))
assert extra1 == extra2