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import unittest
from test.test_string._support import TStringBaseCase, fstring
class TestTString(unittest.TestCase, TStringBaseCase):
def test_string_representation(self):
# Test __repr__
t = t"Hello"
self.assertEqual(repr(t), "Template(strings=('Hello',), interpolations=())")
name = "Python"
t = t"Hello, {name}"
self.assertEqual(repr(t),
"Template(strings=('Hello, ', ''), "
"interpolations=(Interpolation('Python', 'name', None, ''),))"
)
def test_interpolation_basics(self):
# Test basic interpolation
name = "Python"
t = t"Hello, {name}"
self.assertTStringEqual(t, ("Hello, ", ""), [(name, "name")])
self.assertEqual(fstring(t), "Hello, Python")
# Multiple interpolations
first = "Python"
last = "Developer"
t = t"{first} {last}"
self.assertTStringEqual(
t, ("", " ", ""), [(first, 'first'), (last, 'last')]
)
self.assertEqual(fstring(t), "Python Developer")
# Interpolation with expressions
a = 10
b = 20
t = t"Sum: {a + b}"
self.assertTStringEqual(t, ("Sum: ", ""), [(a + b, "a + b")])
self.assertEqual(fstring(t), "Sum: 30")
# Interpolation with function
def square(x):
return x * x
t = t"Square: {square(5)}"
self.assertTStringEqual(
t, ("Square: ", ""), [(square(5), "square(5)")]
)
self.assertEqual(fstring(t), "Square: 25")
# Test attribute access in expressions
class Person:
def __init__(self, name):
self.name = name
def upper(self):
return self.name.upper()
person = Person("Alice")
t = t"Name: {person.name}"
self.assertTStringEqual(
t, ("Name: ", ""), [(person.name, "person.name")]
)
self.assertEqual(fstring(t), "Name: Alice")
# Test method calls
t = t"Name: {person.upper()}"
self.assertTStringEqual(
t, ("Name: ", ""), [(person.upper(), "person.upper()")]
)
self.assertEqual(fstring(t), "Name: ALICE")
# Test dictionary access
data = {"name": "Bob", "age": 30}
t = t"Name: {data['name']}, Age: {data['age']}"
self.assertTStringEqual(
t, ("Name: ", ", Age: ", ""),
[(data["name"], "data['name']"), (data["age"], "data['age']")],
)
self.assertEqual(fstring(t), "Name: Bob, Age: 30")
def test_format_specifiers(self):
# Test basic format specifiers
value = 3.14159
t = t"Pi: {value:.2f}"
self.assertTStringEqual(
t, ("Pi: ", ""), [(value, "value", None, ".2f")]
)
self.assertEqual(fstring(t), "Pi: 3.14")
def test_conversions(self):
# Test !s conversion (str)
obj = object()
t = t"Object: {obj!s}"
self.assertTStringEqual(t, ("Object: ", ""), [(obj, "obj", "s")])
self.assertEqual(fstring(t), f"Object: {str(obj)}")
# Test !r conversion (repr)
t = t"Data: {obj!r}"
self.assertTStringEqual(t, ("Data: ", ""), [(obj, "obj", "r")])
self.assertEqual(fstring(t), f"Data: {repr(obj)}")
# Test !a conversion (ascii)
text = "Café"
t = t"ASCII: {text!a}"
self.assertTStringEqual(t, ("ASCII: ", ""), [(text, "text", "a")])
self.assertEqual(fstring(t), f"ASCII: {ascii(text)}")
# Test !z conversion (error)
num = 1
with self.assertRaises(SyntaxError):
eval("t'{num!z}'")
def test_debug_specifier(self):
# Test debug specifier
value = 42
t = t"Value: {value=}"
self.assertTStringEqual(
t, ("Value: value=", ""), [(value, "value", "r")]
)
self.assertEqual(fstring(t), "Value: value=42")
# Test debug specifier with format (conversion default to !r)
t = t"Value: {value=:.2f}"
self.assertTStringEqual(
t, ("Value: value=", ""), [(value, "value", None, ".2f")]
)
self.assertEqual(fstring(t), "Value: value=42.00")
# Test debug specifier with conversion
t = t"Value: {value=!s}"
self.assertTStringEqual(
t, ("Value: value=", ""), [(value, "value", "s")]
)
# Test white space in debug specifier
t = t"Value: {value = }"
self.assertTStringEqual(
t, ("Value: value = ", ""), [(value, "value", "r")]
)
self.assertEqual(fstring(t), "Value: value = 42")
def test_raw_tstrings(self):
path = r"C:\Users"
t = rt"{path}\Documents"
self.assertTStringEqual(t, ("", r"\Documents"), [(path, "path")])
self.assertEqual(fstring(t), r"C:\Users\Documents")
# Test alternative prefix
t = tr"{path}\Documents"
self.assertTStringEqual(t, ("", r"\Documents"), [(path, "path")])
def test_template_concatenation(self):
# Test template + template
t1 = t"Hello, "
t2 = t"world"
combined = t1 + t2
self.assertTStringEqual(combined, ("Hello, world",), ())
self.assertEqual(fstring(combined), "Hello, world")
# Test template + string
t1 = t"Hello"
combined = t1 + ", world"
self.assertTStringEqual(combined, ("Hello, world",), ())
self.assertEqual(fstring(combined), "Hello, world")
# Test template + template with interpolation
name = "Python"
t1 = t"Hello, "
t2 = t"{name}"
combined = t1 + t2
self.assertTStringEqual(combined, ("Hello, ", ""), [(name, "name")])
self.assertEqual(fstring(combined), "Hello, Python")
# Test string + template
t = "Hello, " + t"{name}"
self.assertTStringEqual(t, ("Hello, ", ""), [(name, "name")])
self.assertEqual(fstring(t), "Hello, Python")
def test_nested_templates(self):
# Test a template inside another template expression
name = "Python"
inner = t"{name}"
t = t"Language: {inner}"
t_interp = t.interpolations[0]
self.assertEqual(t.strings, ("Language: ", ""))
self.assertEqual(t_interp.value.strings, ("", ""))
self.assertEqual(t_interp.value.interpolations[0].value, name)
self.assertEqual(t_interp.value.interpolations[0].expression, "name")
self.assertEqual(t_interp.value.interpolations[0].conversion, None)
self.assertEqual(t_interp.value.interpolations[0].format_spec, "")
self.assertEqual(t_interp.expression, "inner")
self.assertEqual(t_interp.conversion, None)
self.assertEqual(t_interp.format_spec, "")
def test_syntax_errors(self):
for case, err in (
("t'", "unterminated t-string literal"),
("t'''", "unterminated triple-quoted t-string literal"),
("t''''", "unterminated triple-quoted t-string literal"),
("t'{", "'{' was never closed"),
("t'{'", "t-string: expecting '}'"),
("t'{a'", "t-string: expecting '}'"),
("t'}'", "t-string: single '}' is not allowed"),
("t'{}'", "t-string: valid expression required before '}'"),
("t'{=x}'", "t-string: valid expression required before '='"),
("t'{!x}'", "t-string: valid expression required before '!'"),
("t'{:x}'", "t-string: valid expression required before ':'"),
("t'{x;y}'", "t-string: expecting '=', or '!', or ':', or '}'"),
("t'{x=y}'", "t-string: expecting '!', or ':', or '}'"),
("t'{x!s!}'", "t-string: expecting ':' or '}'"),
("t'{x!s:'", "t-string: expecting '}', or format specs"),
("t'{x!}'", "t-string: missing conversion character"),
("t'{x=!}'", "t-string: missing conversion character"),
("t'{x!z}'", "t-string: invalid conversion character 'z': "
"expected 's', 'r', or 'a'"),
("t'{lambda:1}'", "t-string: lambda expressions are not allowed "
"without parentheses"),
("t'{x:{;}}'", "t-string: expecting a valid expression after '{'"),
):
with self.subTest(case), self.assertRaisesRegex(SyntaxError, err):
eval(case)
def test_runtime_errors(self):
# Test missing variables
with self.assertRaises(NameError):
eval("t'Hello, {name}'")
def test_literal_concatenation(self):
# Test concatenation of t-string literals
t = t"Hello, " t"world"
self.assertTStringEqual(t, ("Hello, world",), ())
self.assertEqual(fstring(t), "Hello, world")
# Test concatenation with interpolation
name = "Python"
t = t"Hello, " t"{name}"
self.assertTStringEqual(t, ("Hello, ", ""), [(name, "name")])
self.assertEqual(fstring(t), "Hello, Python")
# Test concatenation with string literal
name = "Python"
t = t"Hello, {name}" "and welcome!"
self.assertTStringEqual(
t, ("Hello, ", "and welcome!"), [(name, "name")]
)
self.assertEqual(fstring(t), "Hello, Pythonand welcome!")
# Test concatenation with Unicode literal
name = "Python"
t = t"Hello, {name}" u"and welcome!"
self.assertTStringEqual(
t, ("Hello, ", "and welcome!"), [(name, "name")]
)
self.assertEqual(fstring(t), "Hello, Pythonand welcome!")
# Test concatenation with f-string literal
tab = '\t'
t = t"Tab: {tab}. " f"f-tab: {tab}."
self.assertTStringEqual(t, ("Tab: ", ". f-tab: \t."), [(tab, "tab")])
self.assertEqual(fstring(t), "Tab: \t. f-tab: \t.")
# Test concatenation with raw string literal
tab = '\t'
t = t"Tab: {tab}. " r"Raw tab: \t."
self.assertTStringEqual(
t, ("Tab: ", r". Raw tab: \t."), [(tab, "tab")]
)
self.assertEqual(fstring(t), "Tab: \t. Raw tab: \\t.")
# Test concatenation with raw f-string literal
tab = '\t'
t = t"Tab: {tab}. " rf"f-tab: {tab}. Raw tab: \t."
self.assertTStringEqual(
t, ("Tab: ", ". f-tab: \t. Raw tab: \\t."), [(tab, "tab")]
)
self.assertEqual(fstring(t), "Tab: \t. f-tab: \t. Raw tab: \\t.")
what = 't'
expected_msg = 'cannot mix bytes and nonbytes literals'
for case in (
"t'{what}-string literal' b'bytes literal'",
"t'{what}-string literal' br'raw bytes literal'",
):
with self.assertRaisesRegex(SyntaxError, expected_msg):
eval(case)
def test_triple_quoted(self):
# Test triple-quoted t-strings
t = t"""
Hello,
world
"""
self.assertTStringEqual(
t, ("\n Hello,\n world\n ",), ()
)
self.assertEqual(fstring(t), "\n Hello,\n world\n ")
# Test triple-quoted with interpolation
name = "Python"
t = t"""
Hello,
{name}
"""
self.assertTStringEqual(
t, ("\n Hello,\n ", "\n "), [(name, "name")]
)
self.assertEqual(fstring(t), "\n Hello,\n Python\n ")
if __name__ == '__main__':
unittest.main()
|
