How to use the black.lib2to3_parse function in black
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psf / black / tests / test_black.py View on Github 
def assertFormatEqual(self, expected: str, actual: str) -> None:
if actual != expected and not os.environ.get("SKIP_AST_PRINT"):
bdv: black.DebugVisitor[Any]
black.out("Expected tree:", fg="green")
try:
exp_node = black.lib2to3_parse(expected)
bdv = black.DebugVisitor()
list(bdv.visit(exp_node))
except Exception as ve:
black.err(str(ve))
black.out("Actual tree:", fg="red")
try:
exp_node = black.lib2to3_parse(actual)
bdv = black.DebugVisitor()
list(bdv.visit(exp_node))
except Exception as ve:
black.err(str(ve))
self.assertEqual(expected, actual)node = black.lib2to3_parse("def f(*, arg): ...\n")
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse("def f(*, arg,): ...\n")
self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA_IN_DEF})
node = black.lib2to3_parse("f(*arg,)\n")
self.assertEqual(
black.get_features_used(node), {Feature.TRAILING_COMMA_IN_CALL}
)
node = black.lib2to3_parse("def f(*, arg): f'string'\n")
self.assertEqual(black.get_features_used(node), {Feature.F_STRINGS})
node = black.lib2to3_parse("123_456\n")
self.assertEqual(black.get_features_used(node), {Feature.NUMERIC_UNDERSCORES})
node = black.lib2to3_parse("123456\n")
self.assertEqual(black.get_features_used(node), set())
source, expected = read_data("function")
node = black.lib2to3_parse(source)
expected_features = {
Feature.TRAILING_COMMA_IN_CALL,
Feature.TRAILING_COMMA_IN_DEF,
Feature.F_STRINGS,
}
self.assertEqual(black.get_features_used(node), expected_features)
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), expected_features)
source, expected = read_data("expression")
node = black.lib2to3_parse(source)
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), set())def test_get_future_imports(self) -> None:
node = black.lib2to3_parse("\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import black\n")
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import multiple, imports\n")
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import (parenthesized, imports)\n")
self.assertEqual({"parenthesized", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import multiple\nfrom __future__ import imports\n"
)
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("# comment\nfrom __future__ import black\n")
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse('"""docstring"""\nfrom __future__ import black\n')
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("some(other, code)\nfrom __future__ import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse("from some.module import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import unicode_literals as _unicode_literals"
)
self.assertEqual({"unicode_literals"}, black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import unicode_literals as _lol, print"
)
self.assertEqual({"unicode_literals", "print"}, black.get_future_imports(node))def test_get_features_used(self) -> None:
node = black.lib2to3_parse("def f(*, arg): ...\n")
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse("def f(*, arg,): ...\n")
self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA_IN_DEF})
node = black.lib2to3_parse("f(*arg,)\n")
self.assertEqual(
black.get_features_used(node), {Feature.TRAILING_COMMA_IN_CALL}
)
node = black.lib2to3_parse("def f(*, arg): f'string'\n")
self.assertEqual(black.get_features_used(node), {Feature.F_STRINGS})
node = black.lib2to3_parse("123_456\n")
self.assertEqual(black.get_features_used(node), {Feature.NUMERIC_UNDERSCORES})
node = black.lib2to3_parse("123456\n")
self.assertEqual(black.get_features_used(node), set())
source, expected = read_data("function")
node = black.lib2to3_parse(source)
expected_features = {
Feature.TRAILING_COMMA_IN_CALL,
Feature.TRAILING_COMMA_IN_DEF,
Feature.F_STRINGS,
}def test_get_features_used(self) -> None:
node = black.lib2to3_parse("def f(*, arg): ...\n")
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse("def f(*, arg,): ...\n")
self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA_IN_DEF})
node = black.lib2to3_parse("f(*arg,)\n")
self.assertEqual(
black.get_features_used(node), {Feature.TRAILING_COMMA_IN_CALL}
)
node = black.lib2to3_parse("def f(*, arg): f'string'\n")
self.assertEqual(black.get_features_used(node), {Feature.F_STRINGS})
node = black.lib2to3_parse("123_456\n")
self.assertEqual(black.get_features_used(node), {Feature.NUMERIC_UNDERSCORES})
node = black.lib2to3_parse("123456\n")
self.assertEqual(black.get_features_used(node), set())
source, expected = read_data("function")
node = black.lib2to3_parse(source)
expected_features = {
Feature.TRAILING_COMMA_IN_CALL,
Feature.TRAILING_COMMA_IN_DEF,self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import multiple, imports\n")
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import (parenthesized, imports)\n")
self.assertEqual({"parenthesized", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import multiple\nfrom __future__ import imports\n"
)
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("# comment\nfrom __future__ import black\n")
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse('"""docstring"""\nfrom __future__ import black\n')
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("some(other, code)\nfrom __future__ import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse("from some.module import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import unicode_literals as _unicode_literals"
)
self.assertEqual({"unicode_literals"}, black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import unicode_literals as _lol, print"
)
self.assertEqual({"unicode_literals", "print"}, black.get_future_imports(node))def test_get_future_imports(self) -> None:
node = black.lib2to3_parse("\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import black\n")
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import multiple, imports\n")
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("from __future__ import (parenthesized, imports)\n")
self.assertEqual({"parenthesized", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import multiple\nfrom __future__ import imports\n"
)
self.assertEqual({"multiple", "imports"}, black.get_future_imports(node))
node = black.lib2to3_parse("# comment\nfrom __future__ import black\n")
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse('"""docstring"""\nfrom __future__ import black\n')
self.assertEqual({"black"}, black.get_future_imports(node))
node = black.lib2to3_parse("some(other, code)\nfrom __future__ import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse("from some.module import black\n")
self.assertEqual(set(), black.get_future_imports(node))
node = black.lib2to3_parse(
"from __future__ import unicode_literals as _unicode_literals"
)def test_lib2to3_parse(self) -> None:
with self.assertRaises(black.InvalidInput):
black.lib2to3_parse("invalid syntax")
straddling = "x + y"
black.lib2to3_parse(straddling)
black.lib2to3_parse(straddling, {TargetVersion.PY27})
black.lib2to3_parse(straddling, {TargetVersion.PY36})
black.lib2to3_parse(straddling, {TargetVersion.PY27, TargetVersion.PY36})
py2_only = "print x"
black.lib2to3_parse(py2_only)
black.lib2to3_parse(py2_only, {TargetVersion.PY27})
with self.assertRaises(black.InvalidInput):
black.lib2to3_parse(py2_only, {TargetVersion.PY36})
with self.assertRaises(black.InvalidInput):
black.lib2to3_parse(py2_only, {TargetVersion.PY27, TargetVersion.PY36})
py3_only = "exec(x, end=y)"
black.lib2to3_parse(py3_only)
with self.assertRaises(black.InvalidInput):
black.lib2to3_parse(py3_only, {TargetVersion.PY27})
black.lib2to3_parse(py3_only, {TargetVersion.PY36})def test_get_features_used(self) -> None:
node = black.lib2to3_parse("def f(*, arg): ...\n")
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse("def f(*, arg,): ...\n")
self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA_IN_DEF})
node = black.lib2to3_parse("f(*arg,)\n")
self.assertEqual(
black.get_features_used(node), {Feature.TRAILING_COMMA_IN_CALL}
)
node = black.lib2to3_parse("def f(*, arg): f'string'\n")
self.assertEqual(black.get_features_used(node), {Feature.F_STRINGS})
node = black.lib2to3_parse("123_456\n")
self.assertEqual(black.get_features_used(node), {Feature.NUMERIC_UNDERSCORES})
node = black.lib2to3_parse("123456\n")
self.assertEqual(black.get_features_used(node), set())
source, expected = read_data("function")
node = black.lib2to3_parse(source)
expected_features = {
Feature.TRAILING_COMMA_IN_CALL,
Feature.TRAILING_COMMA_IN_DEF,
Feature.F_STRINGS,
}
self.assertEqual(black.get_features_used(node), expected_features)
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), expected_features)
source, expected = read_data("expression")
node = black.lib2to3_parse(source)
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), set())node = black.lib2to3_parse("123456\n")
self.assertEqual(black.get_features_used(node), set())
source, expected = read_data("function")
node = black.lib2to3_parse(source)
expected_features = {
Feature.TRAILING_COMMA_IN_CALL,
Feature.TRAILING_COMMA_IN_DEF,
Feature.F_STRINGS,
}
self.assertEqual(black.get_features_used(node), expected_features)
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), expected_features)
source, expected = read_data("expression")
node = black.lib2to3_parse(source)
self.assertEqual(black.get_features_used(node), set())
node = black.lib2to3_parse(expected)
self.assertEqual(black.get_features_used(node), set())
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