File: test_reader.py

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import sys
import traceback
from math import isnan

import pytest

from hy import PrematureEndOfInput
from hy.errors import hy_exc_handler
from hy.models import (
    Bytes,
    Complex,
    Dict,
    Expression,
    Float,
    FString,
    Integer,
    Keyword,
    List,
    Set,
    String,
    Symbol,
)
from hy.reader import read_many
from hy.reader.exceptions import LexException


def tokenize(*args, **kwargs):
    return list(read_many(*args, **kwargs))


def peoi():
    return pytest.raises(PrematureEndOfInput)


def lexe():
    return pytest.raises(LexException)


def check_ex(einfo, expected):
    assert [
        x.rstrip() for x in traceback.format_exception_only(einfo.type, einfo.value)
    ] == expected


def check_trace_output(capsys, execinfo, expected):
    sys.__excepthook__(execinfo.type, execinfo.value, execinfo.tb)
    captured_wo_filtering = capsys.readouterr()[-1].strip("\n")

    hy_exc_handler(execinfo.type, execinfo.value, execinfo.tb)
    captured_w_filtering = capsys.readouterr()[-1].strip("\n")

    output = [x.rstrip() for x in captured_w_filtering.split("\n") if not (set(x) <= {" ", "^", "~"})]

    # Make sure the filtered frames aren't the same as the unfiltered ones.
    assert output != captured_wo_filtering.split("\n")
    # Remove the origin frame lines.
    assert output[5:] == expected


def test_lex_exception():
    """Ensure tokenize throws a fit on a partial input"""
    with peoi():
        tokenize("(foo")
    with peoi():
        tokenize("{foo bar")
    with peoi():
        tokenize("(defn foo [bar]")
    with peoi():
        tokenize('(foo "bar')


def test_unbalanced_exception():
    """Ensure the tokenization fails on unbalanced expressions"""
    with lexe():
        tokenize("(bar))")
    with lexe():
        tokenize("(baz [quux]])")


def test_lex_single_quote_err():
    # https://github.com/hylang/hy/issues/1252
    with lexe() as execinfo:
        tokenize("' ")
    assert type(execinfo.value) is PrematureEndOfInput
    assert execinfo.value.msg == "Premature end of input while attempting to parse one form"


def test_lex_expression_symbols():
    """Make sure that expressions produce symbols"""
    objs = tokenize("(foo bar)")
    assert objs == [Expression([Symbol("foo"), Symbol("bar")])]


def test_symbol_and_sugar():
    # https://github.com/hylang/hy/issues/1798

    s = Symbol

    def e(*x):
        return Expression(x)

    for char, head in (
        ("'", "quote"),
        ("`", "quasiquote"),
        ("~", "unquote"),
        ("~@", "unquote-splice"),
    ):
        for string in (f"a{s1}{char}{s2}b" for s1 in ("", " ") for s2 in ("", " ")):
            assert tokenize(string) == [s("a"), e(s(head), s("b"))]

    assert tokenize("a~ @b") == tokenize("a ~ @b") == [s("a"), e(s("unquote"), s("@b"))]


def test_lex_expression_strings():
    """Test that expressions can produce strings"""
    objs = tokenize('(foo "bar")')
    assert objs == [Expression([Symbol("foo"), String("bar")])]


def test_lex_expression_integer():
    """Make sure expressions can produce integers"""
    objs = tokenize("(foo 2)")
    assert objs == [Expression([Symbol("foo"), Integer(2)])]


def test_lex_symbols():
    """Make sure that symbols are valid expressions"""
    objs = tokenize("foo ")
    assert objs == [Symbol("foo")]


def test_lex_strings():
    """Make sure that strings are valid expressions"""
    objs = tokenize('"foo"')
    assert objs == [String("foo")]
    # Make sure backslash-escaped newlines work (see issue #831)
    objs = tokenize(
        r"""
"a\
bc"
"""
    )
    assert objs == [String("abc")]


def test_lex_strings_exception():
    """Make sure tokenize throws when codec can't decode some bytes"""
    with lexe() as execinfo:
        tokenize('"\\x8"')
    check_ex(
        execinfo,
        [
            '  File "<string>", line 1',
            '    "\\x8"',
            "        ^",
            "hy.reader.exceptions.LexException:"
            " 'unicodeescape' codec can't decode bytes in position 0-2:"
            " truncated \\xXX escape",
        ],
    )


def test_lex_bracket_strings():

    objs = tokenize("#[my delim[hello world]my delim]")
    assert objs == [String("hello world")]
    assert objs[0].brackets == "my delim"

    objs = tokenize("#[[squid]]")
    assert objs == [String("squid")]
    assert objs[0].brackets == ""


def test_lex_integers():
    assert tokenize("42") == [Integer(42)]
    assert tokenize("0x80") == [Integer(128)]
    assert tokenize("0o1232") == [Integer(666)]
    assert tokenize("0b1011101") == [Integer(93)]


def test_lex_expression_float():
    """Make sure expressions can produce floats"""
    objs = tokenize("(foo 2.)")
    assert objs == [Expression([Symbol("foo"), Float(2.0)])]
    objs = tokenize("(foo -0.5)")
    assert objs == [Expression([Symbol("foo"), Float(-0.5)])]
    objs = tokenize("(foo 1.e7)")
    assert objs == [Expression([Symbol("foo"), Float(1.0e7)])]


def test_lex_big_float():
    # https://github.com/hylang/hy/issues/1448
    assert tokenize("1e900") == [Float(1e900)]
    assert tokenize("1e900-1e900j") == [Complex(1e900, -1e900)]


def test_lex_nan_and_inf():

    assert isnan(tokenize("NaN")[0])
    assert tokenize("Nan") == [Symbol("Nan")]
    assert tokenize("nan") == [Symbol("nan")]
    assert tokenize("NAN") == [Symbol("NAN")]

    assert tokenize("Inf") == [Float(float("inf"))]
    assert tokenize("inf") == [Symbol("inf")]
    assert tokenize("INF") == [Symbol("INF")]

    assert tokenize("-Inf") == [Float(float("-inf"))]
    assert tokenize("-inf") == [Symbol("-inf")]
    assert tokenize("-INF") == [Symbol("-INF")]


def test_lex_expression_complex():
    """Make sure expressions can produce complex"""

    def t(x):
        return tokenize("(foo {})".format(x))

    def f(x):
        return [Expression([Symbol("foo"), x])]

    assert t("2j") == f(Complex(2.0j))
    assert t("2J") == f(Complex(2.0j))
    assert t("2.j") == f(Complex(2.0j))
    assert t("2.J") == f(Complex(2.0j))
    assert t("-0.5j") == f(Complex(-0.5j))
    assert t("1.e7j") == f(Complex(1e7j))
    assert t("1.e7J") == f(Complex(1e7j))
    assert t("j") == f(Symbol("j"))
    assert t("J") == f(Symbol("J"))
    assert isnan(t("NaNj")[0][1].imag)
    assert t("nanj") == f(Symbol("nanj"))
    assert t("Inf+Infj") == f(Complex(complex(float("inf"), float("inf"))))
    assert t("Inf-Infj") == f(Complex(complex(float("inf"), float("-inf"))))
    assert t("Inf-INFj") == f(Symbol("Inf-INFj"))

    # https://github.com/hylang/hy/issues/2521
    assert isnan(t("NaNJ")[0][1].imag)
    assert t("nanJ") == f(Symbol("nanJ"))
    assert t("InfJ") == f(Complex(complex(0, float("inf"))))
    assert t("iNfJ") == f(Symbol("iNfJ"))
    assert t("Inf-INFJ") == f(Symbol("Inf-INFJ"))


def test_lex_digit_separators():

    assert tokenize("1_000_000") == [Integer(1000000)]
    assert tokenize("1,000,000") == [Integer(1000000)]
    assert tokenize("1,000_000") == [Integer(1000000)]
    assert tokenize("1_000,000") == [Integer(1000000)]
    # https://github.com/hylang/hy/issues/1340
    assert tokenize("_42") == [Symbol("_42")]

    assert tokenize("0x_af") == [Integer(0xAF)]
    assert tokenize("0x,af") == [Integer(0xAF)]
    assert tokenize("0_xaf") == [Integer(0xAF)]
    assert tokenize("0b_010") == [Integer(0b010)]
    assert tokenize("0b,010") == [Integer(0b010)]
    assert tokenize("0o_373") == [Integer(0o373)]
    assert tokenize("0o,373") == [Integer(0o373)]

    assert tokenize("1_2._3,4") == [Float(12.34)]
    assert tokenize("1_2e_3,4") == [Float(12e34)]
    assert tokenize("1,0_00j,") == [Complex(1000j)]

    assert tokenize("1,,,,___,____,,__,,2__,,,__") == [Integer(12)]
    assert tokenize("_1,,,,___,____,,__,,2__,,,__") == [
        Symbol("_1,,,,___,____,,__,,2__,,,__")
    ]
    assert tokenize("1,,,,___,____,,__,,2__,q,__") == [
        Symbol("1,,,,___,____,,__,,2__,q,__")
    ]


def test_leading_zero():
    assert tokenize("0") == [Integer(0)]
    assert tokenize("0000") == [Integer(0)]
    assert tokenize("010") == [Integer(10)]
    assert tokenize("000010") == [Integer(10)]
    assert tokenize("000010.00") == [Float(10)]
    assert tokenize("010+000010j") == [Complex(10 + 10j)]


def test_dotted_identifiers():
    t = tokenize

    assert t("foo.bar") == t("(. foo bar)")
    assert t("foo.bar.baz") == t("(. foo bar baz)")
    assert t(".foo") == t("(. None foo)")
    assert t(".foo.bar.baz") == t("(. None foo bar baz)")
    assert t("..foo") == t("(.. None foo)")
    assert t("..foo.bar.baz") == t("(.. None foo bar baz)")


def test_lex_bad_attrs():
    with lexe() as execinfo:
        tokenize("1.foo")
    check_ex(
        execinfo,
        [
            '  File "<string>", line 1',
            "    1.foo",
            "        ^",
            "hy.reader.exceptions.LexException: The parts of a dotted identifier must be symbols",
        ],
    )

    with lexe():
        tokenize("0.foo")
    with lexe():
        tokenize("1.5.foo")
    with lexe():
        tokenize("1e3.foo")
    with lexe():
        tokenize("5j.foo")
    with lexe():
        tokenize("3+5j.foo")
    with lexe():
        tokenize("3.1+5.1j.foo")
    assert tokenize("j.foo")
    with lexe():
        tokenize(":hello.foo")


def test_lists():
    assert tokenize("[1 2 3 4]") == [List(map(Integer, (1, 2, 3, 4)))]


def test_dicts():
    assert tokenize("{1 2  3 4}") == [Dict(map(Integer, (1, 2, 3, 4)))]
    assert tokenize("{1 (+ 1 1) 3 (+ 2 2)}") == [
        Dict(
            (
                Integer(1),
                Expression((Symbol("+"), Integer(1), Integer(1))),
                Integer(3),
                Expression((Symbol("+"), Integer(2), Integer(2))),
            )
        )
    ]


def test_lex_column_counting():
    entry = tokenize("(foo (one two))")[0]
    assert entry.start_line == 1
    assert entry.start_column == 1
    assert entry.end_line == 1
    assert entry.end_column == 15

    symbol = entry[0]
    assert symbol.start_line == 1
    assert symbol.start_column == 2
    assert symbol.end_line == 1
    assert symbol.end_column == 4

    inner_expr = entry[1]
    assert inner_expr.start_line == 1
    assert inner_expr.start_column == 6
    assert inner_expr.end_line == 1
    assert inner_expr.end_column == 14


def test_lex_column_counting_with_literal_newline():
    string, symbol = tokenize('"apple\nblueberry" abc')

    assert string.start_line == 1
    assert string.start_column == 1
    assert string.end_line == 2
    assert string.end_column == 10

    assert symbol.start_line == 2
    assert symbol.start_column == 12
    assert symbol.end_line == 2
    assert symbol.end_column == 14


def test_lex_line_counting_multi():
    """Make sure we can do multi-line tokenization"""
    entries = tokenize(
        """
(foo (one two))
(foo bar)
"""
    )

    entry = entries[0]

    assert entry.start_line == 2
    assert entry.start_column == 1

    assert entry.end_line == 2
    assert entry.end_column == 15

    entry = entries[1]
    assert entry.start_line == 3
    assert entry.start_column == 1

    assert entry.end_line == 3
    assert entry.end_column == 9


def test_lex_line_counting_multi_inner():
    """Make sure we can do multi-line tokenization (inner)"""
    entry = tokenize(
        """(foo
    bar)"""
    )[0]
    inner = entry[0]

    assert inner.start_line == 1
    assert inner.start_column == 2

    inner = entry[1]

    assert inner.start_line == 2
    assert inner.start_column == 5


def test_line_counting_dotted():
    # https://github.com/hylang/hy/issues/2422
    x, = tokenize(";;;;;\na.b")
    for e in (x, *x):
        assert e.start_line == 2


def test_dicts():
    """Ensure that we can tokenize a dict."""
    objs = tokenize("{foo bar bar baz}")
    assert objs == [Dict([Symbol("foo"), Symbol("bar"), Symbol("bar"), Symbol("baz")])]

    objs = tokenize("(bar {foo bar bar baz})")
    assert objs == [
        Expression(
            [
                Symbol("bar"),
                Dict([Symbol("foo"), Symbol("bar"), Symbol("bar"), Symbol("baz")]),
            ]
        )
    ]

    objs = tokenize("{(foo bar) (baz quux)}")
    assert objs == [
        Dict(
            [
                Expression([Symbol("foo"), Symbol("bar")]),
                Expression([Symbol("baz"), Symbol("quux")]),
            ]
        )
    ]


def test_sets():
    """Ensure that we can tokenize a set."""
    objs = tokenize("#{1 2}")
    assert objs == [Set([Integer(1), Integer(2)])]
    objs = tokenize("(bar #{foo bar baz})")
    assert objs == [
        Expression([Symbol("bar"), Set([Symbol("foo"), Symbol("bar"), Symbol("baz")])])
    ]

    objs = tokenize("#{(foo bar) (baz quux)}")
    assert objs == [
        Set(
            [
                Expression([Symbol("foo"), Symbol("bar")]),
                Expression([Symbol("baz"), Symbol("quux")]),
            ]
        )
    ]

    # Duplicate items in a literal set should be okay (and should
    # be preserved).
    objs = tokenize("#{1 2 1 1 2 1}")
    assert objs == [Set([Integer(n) for n in [1, 2, 1, 1, 2, 1]])]
    assert len(objs[0]) == 6

    # https://github.com/hylang/hy/issues/1120
    objs = tokenize("#{a 1}")
    assert objs == [Set([Symbol("a"), Integer(1)])]


def test_nospace():
    """Ensure we can tokenize without spaces if we have to"""
    entry = tokenize("(foo(one two))")[0]

    assert entry.start_line == 1
    assert entry.start_column == 1

    assert entry.end_line == 1
    assert entry.end_column == 14

    entry = entry[1]
    assert entry.start_line == 1
    assert entry.start_column == 5

    assert entry.end_line == 1
    assert entry.end_column == 13


def test_string_prefixes():
    s = lambda x: tokenize(x)[0]

    assert s(r'b"hello"') == Bytes(b"hello")
    assert s(r'rb"hello"') == Bytes(b"hello")
    assert s(r'fr"hello"') == FString([String("hello")])

    for bad in list("zRBFu") + ["bf", "rr", "rbr"]:
        with lexe():
            s(bad + '"hello"')


def test_escapes():
    s = lambda x: tokenize(x)[0]

    # A valid escape sequence
    assert s(r'"foo\x5a"') == String("fooZ")
    assert s(r'b"foo\x5a"') == Bytes(b"fooZ")
    # In a raw string
    assert s(r'r"foo\x5a"') == String("foo\\x5a")
    assert s(r'rb"foo\x5a"') == Bytes(b"foo\\x5a")
    # An invalid escape sequence
    with lexe():
        s(r'"foo\s"')
    with lexe():
        s(r'b"foo\s"')
    # In a raw string
    assert s(r'r"foo\s"') == String("foo\\s")
    assert s(r'rb"foo\s"') == Bytes(b"foo\\s")
    # An escape sequence that's valid in strings, but not bytes.
    assert s(r'"foo\u005a"') == String("fooZ")
    with lexe():
        s(r'b"foo\u005a"')


def test_unicode_escapes():
    """Ensure unicode escapes are handled correctly"""
    s = r'"a\xac\u1234\u20ac\U00008000"'
    assert len(s) == 29
    entry = tokenize(s)[0]
    assert len(entry) == 5
    assert [ord(x) for x in entry] == [97, 172, 4660, 8364, 32768]


def test_complex():
    """Ensure we tokenize complex numbers properly"""
    # This is a regression test for #143
    entry = tokenize("(1j)")[0][0]
    assert entry == Complex("1.0j")
    entry = tokenize("(1J)")[0][0]
    assert entry == Complex("1.0j")
    entry = tokenize("(j)")[0][0]
    assert entry == Symbol("j")
    entry = tokenize("(J)")[0][0]
    assert entry == Symbol("J")


def test_lex_comment_382():
    """Ensure that we can tokenize sources with a comment at the end"""
    entry = tokenize("foo ;bar\n;baz")
    assert entry == [Symbol("foo")]


def test_discard():
    """Check that discarded terms are removed properly."""
    # empty
    assert tokenize("") == []
    # single
    assert tokenize("#_ 1") == []
    # multiple
    assert tokenize("#_ 1 #_ 2") == []
    assert tokenize("#_ 1 #_ 2 #_ 3") == []
    # nested discard
    assert tokenize("#_ #_ 1 2") == []
    assert tokenize("#_ #_ #_ 1 2 3") == []
    # trailing
    assert tokenize("0") == [Integer(0)]
    assert tokenize("0 #_ 1") == [Integer(0)]
    assert tokenize("0 #_ 1 #_ 2") == [Integer(0)]
    # leading
    assert tokenize("2") == [Integer(2)]
    assert tokenize("#_ 1 2") == [Integer(2)]
    assert tokenize("#_ 0 #_ 1 2") == [Integer(2)]
    assert tokenize("#_ #_ 0 1 2") == [Integer(2)]
    # both
    assert tokenize("#_ 1 2 #_ 3") == [Integer(2)]
    assert tokenize("#_ 0 #_ 1 2 #_ #_ 3 4") == [Integer(2)]
    # inside
    assert tokenize("0 #_ 1 2") == [Integer(0), Integer(2)]
    assert tokenize("0 #_ 1 #_ 2 3") == [Integer(0), Integer(3)]
    assert tokenize("0 #_ #_ 1 2 3") == [Integer(0), Integer(3)]
    # in List
    assert tokenize("[]") == [List([])]
    assert tokenize("[#_ 1]") == [List([])]
    assert tokenize("[#_ 1 #_ 2]") == [List([])]
    assert tokenize("[#_ #_ 1 2]") == [List([])]
    assert tokenize("[0]") == [List([Integer(0)])]
    assert tokenize("[0 #_ 1]") == [List([Integer(0)])]
    assert tokenize("[0 #_ 1 #_ 2]") == [List([Integer(0)])]
    assert tokenize("[2]") == [List([Integer(2)])]
    assert tokenize("[#_ 1 2]") == [List([Integer(2)])]
    assert tokenize("[#_ 0 #_ 1 2]") == [List([Integer(2)])]
    assert tokenize("[#_ #_ 0 1 2]") == [List([Integer(2)])]
    # in Set
    assert tokenize("#{}") == [Set()]
    assert tokenize("#{#_ 1}") == [Set()]
    assert tokenize("#{0 #_ 1}") == [Set([Integer(0)])]
    assert tokenize("#{#_ 1 0}") == [Set([Integer(0)])]
    # in Dict
    assert tokenize("{}") == [Dict()]
    assert tokenize("{#_ 1}") == [Dict()]
    assert tokenize("{#_ 0 1 2}") == [Dict([Integer(1), Integer(2)])]
    assert tokenize("{1 #_ 0 2}") == [Dict([Integer(1), Integer(2)])]
    assert tokenize("{1 2 #_ 0}") == [Dict([Integer(1), Integer(2)])]
    # in Expression
    assert tokenize("()") == [Expression()]
    assert tokenize("(#_ foo)") == [Expression()]
    assert tokenize("(#_ foo bar)") == [Expression([Symbol("bar")])]
    assert tokenize("(foo #_ bar)") == [Expression([Symbol("foo")])]
    assert tokenize("(foo :bar 1)") == [
        Expression([Symbol("foo"), Keyword("bar"), Integer(1)])
    ]
    assert tokenize("(foo #_ :bar 1)") == [Expression([Symbol("foo"), Integer(1)])]
    assert tokenize("(foo :bar #_ 1)") == [Expression([Symbol("foo"), Keyword("bar")])]
    # discard term with nesting
    assert tokenize("[1 2 #_ [a b c [d e [f g] h]] 3 4]") == [
        List([Integer(1), Integer(2), Integer(3), Integer(4)])
    ]
    # discard with other prefix syntax
    assert tokenize("a #_ 'b c") == [Symbol("a"), Symbol("c")]
    assert tokenize("a '#_ b c") == [
        Symbol("a"),
        Expression([Symbol("quote"), Symbol("c")]),
    ]
    assert tokenize("a '#_ b #_ c d") == [
        Symbol("a"),
        Expression([Symbol("quote"), Symbol("d")]),
    ]
    assert tokenize("a '#_ #_ b c d") == [
        Symbol("a"),
        Expression([Symbol("quote"), Symbol("d")]),
    ]


def test_lex_exception_filtering(capsys):
    """Confirm that the exception filtering works for lexer errors."""

    # First, test for PrematureEndOfInput
    with peoi() as execinfo:
        tokenize(" \n (foo\n       \n")
    check_trace_output(
        capsys,
        execinfo,
        [
            '  File "<string>", line 2',
            "    (foo",
            "hy.PrematureEndOfInput: Premature end of input while attempting to parse one form",
        ],
    )

    # Now, for a generic LexException
    with lexe() as execinfo:
        tokenize("  \n\n  1.foo   ")
    check_trace_output(
        capsys,
        execinfo,
        [
            '  File "<string>", line 3',
            "    1.foo",
            "hy.reader.exceptions.LexException: The parts of a dotted identifier must be symbols",
        ],
    )


def test_read_error():
    """Compilation errors from code that was parsed with `hy.read` should have an arrow
    pointing to the source position where the error arose."""

    import traceback
    import hy
    from hy.errors import HySyntaxError, hy_exc_handler

    with pytest.raises(HySyntaxError) as e:
        hy.eval(hy.read("(do (defn))"))

    assert "".join(traceback.format_exception_only(e.type, e.value)).startswith(
        '  File "<string>", line 1\n    (do (defn))\n         ^'
    )


def test_shebang():
    from hy.errors import HySyntaxError

    with pytest.raises(HySyntaxError):
        # By default, `read_many` doesn't allow a shebang.
        assert tokenize('#!/usr/bin/env hy\n5')
    assert (tokenize('#!/usr/bin/env hy\n5', skip_shebang = True) ==
        [Integer(5)])


def test_reader_class_reprs():
    "Don't show internal modules in which these classes are defined."
    assert repr(hy.Reader) == "<class 'hy.Reader'>"
    assert repr(hy.HyReader) == "<class 'hy.HyReader'>"