# Copyright 2019 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Tests for attribute_checker.py."""

import unittest
from compiler.front_end import attribute_checker
from compiler.front_end import glue
from compiler.front_end import test_util
from compiler.util import ir_pb2
from compiler.util import error
from compiler.util import ir_util

# These are not shared with attribute_checker.py because their values are part
# of the contract with back ends.
_BYTE_ORDER = "byte_order"
_FIXED_SIZE = "fixed_size_in_bits"


def _make_ir_from_emb(emb_text, name="m.emb"):
  ir, unused_debug_info, errors = glue.parse_emboss_file(
      name,
      test_util.dict_file_reader({name: emb_text}),
      stop_before_step="normalize_and_verify")
  assert not errors
  return ir


class NormalizeIrTest(unittest.TestCase):

  def test_rejects_may_be_used_as_integer(self):
    enum_ir = _make_ir_from_emb("enum Foo:\n"
                                "  [may_be_used_as_integer: false]\n"
                                "  VALUE = 1\n")
    enum_type_ir = enum_ir.module[0].type[0]
    self.assertEqual([[
        error.error(
            "m.emb", enum_type_ir.attribute[0].name.source_location,
            "Unknown attribute 'may_be_used_as_integer' on enum 'Foo'.")
    ]], attribute_checker.normalize_and_verify(enum_ir))

  def test_adds_fixed_size_attribute_to_struct(self):
    # field2 is intentionally after field3, in order to trigger certain code
    # paths in attribute_checker.py.
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  4 [+4]  UInt  field2\n"
                                  "  2 [+2]  UInt  field3\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    size_attr = ir_util.get_attribute(struct_ir.module[0].type[0].attribute,
                                      _FIXED_SIZE)
    self.assertEqual(64, ir_util.constant_value(size_attr.expression))
    self.assertEqual(struct_ir.module[0].type[0].source_location,
                     size_attr.source_location)

  def test_adds_fixed_size_attribute_to_struct_with_virtual_field(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  let field2 = field1\n"
                                  "  2 [+2]  UInt  field3\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    size_attr = ir_util.get_attribute(struct_ir.module[0].type[0].attribute,
                                      _FIXED_SIZE)
    self.assertEqual(32, ir_util.constant_value(size_attr.expression))
    self.assertEqual(struct_ir.module[0].type[0].source_location,
                     size_attr.source_location)

  def test_adds_fixed_size_attribute_to_anonymous_bits(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  0 [+4]  bits:\n"
                                  "    0 [+8]  UInt  field\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    size_attr = ir_util.get_attribute(struct_ir.module[0].type[0].attribute,
                                      _FIXED_SIZE)
    self.assertEqual(32, ir_util.constant_value(size_attr.expression))
    bits_size_attr = ir_util.get_attribute(
        struct_ir.module[0].type[0].subtype[0].attribute, _FIXED_SIZE)
    self.assertEqual(8, ir_util.constant_value(bits_size_attr.expression))
    self.assertEqual(struct_ir.module[0].type[0].source_location,
                     size_attr.source_location)

  def test_does_not_add_fixed_size_attribute_to_variable_size_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  0 [+4]  UInt      n\n"
                                  "  4 [+n]  UInt:8[]  payload\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    self.assertIsNone(ir_util.get_attribute(
        struct_ir.module[0].type[0].attribute, _FIXED_SIZE))

  def test_accepts_correct_fixed_size_and_size_attributes_on_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  [fixed_size_in_bits: 64]\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  2 [+2]  UInt  field2\n"
                                  "  4 [+4]  UInt  field3\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    size_attr = ir_util.get_attribute(struct_ir.module[0].type[0].attribute,
                                      _FIXED_SIZE)
    self.assertTrue(size_attr)
    self.assertEqual(64, ir_util.constant_value(size_attr.expression))

  def test_accepts_correct_size_attribute_on_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  [fixed_size_in_bits: 64]\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  4 [+4]  UInt  field3\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(struct_ir))
    size_attr = ir_util.get_attribute(struct_ir.module[0].type[0].attribute,
                                      _FIXED_SIZE)
    self.assertTrue(size_attr.expression)
    self.assertEqual(64, ir_util.constant_value(size_attr.expression))

  def test_rejects_incorrect_fixed_size_attribute_on_variable_size_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  [fixed_size_in_bits: 8]\n"
                                  "  0 [+4]  UInt      n\n"
                                  "  4 [+n]  UInt:8[]  payload\n")
    struct_type_ir = struct_ir.module[0].type[0]
    self.assertEqual([[error.error(
        "m.emb", struct_type_ir.attribute[0].value.source_location,
        "Struct is marked as fixed size, but contains variable-location "
        "fields.")]], attribute_checker.normalize_and_verify(struct_ir))

  def test_rejects_size_attribute_with_wrong_large_value_on_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  [fixed_size_in_bits: 80]\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  2 [+2]  UInt  field2\n"
                                  "  4 [+4]  UInt  field3\n")
    struct_type_ir = struct_ir.module[0].type[0]
    self.assertEqual([
        [error.error("m.emb", struct_type_ir.attribute[0].value.source_location,
                     "Struct is 64 bits, but is marked as 80 bits.")]
    ], attribute_checker.normalize_and_verify(struct_ir))

  def test_rejects_size_attribute_with_wrong_small_value_on_struct(self):
    struct_ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                                  "struct Foo:\n"
                                  "  [fixed_size_in_bits: 40]\n"
                                  "  0 [+2]  UInt  field1\n"
                                  "  2 [+2]  UInt  field2\n"
                                  "  4 [+4]  UInt  field3\n")
    struct_type_ir = struct_ir.module[0].type[0]
    self.assertEqual([
        [error.error("m.emb", struct_type_ir.attribute[0].value.source_location,
                     "Struct is 64 bits, but is marked as 40 bits.")]
    ], attribute_checker.normalize_and_verify(struct_ir))

  def test_accepts_variable_size_external(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [addressable_unit_size: 1]\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(external_ir))

  def test_accepts_fixed_size_external(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [fixed_size_in_bits: 32]\n"
                                    "  [addressable_unit_size: 1]\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(external_ir))

  def test_rejects_external_with_no_addressable_unit_size_attribute(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [is_integer: false]\n")
    external_type_ir = external_ir.module[0].type[0]
    self.assertEqual([
        [error.error(
            "m.emb", external_type_ir.source_location,
            "Expected 'addressable_unit_size' attribute for external type.")]
    ], attribute_checker.normalize_and_verify(external_ir))

  def test_rejects_is_integer_with_non_constant_value(self):
    external_ir = _make_ir_from_emb(
        "external Foo:\n"
        "  [is_integer: $static_size_in_bits == 1]\n"
        "  [addressable_unit_size: 1]\n")
    external_type_ir = external_ir.module[0].type[0]
    self.assertEqual([
        [error.error(
            "m.emb", external_type_ir.attribute[0].value.source_location,
            "Attribute 'is_integer' must have a constant boolean value.")]
    ], attribute_checker.normalize_and_verify(external_ir))

  def test_rejects_addressable_unit_size_with_non_constant_value(self):
    external_ir = _make_ir_from_emb(
        "external Foo:\n"
        "  [is_integer: true]\n"
        "  [addressable_unit_size: $static_size_in_bits]\n")
    external_type_ir = external_ir.module[0].type[0]
    self.assertEqual([
        [error.error(
            "m.emb", external_type_ir.attribute[1].value.source_location,
            "Attribute 'addressable_unit_size' must have a constant value.")]
    ], attribute_checker.normalize_and_verify(external_ir))

  def test_rejects_external_with_wrong_addressable_unit_size_attribute(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [addressable_unit_size: 4]\n")
    external_type_ir = external_ir.module[0].type[0]
    self.assertEqual([
        [error.error(
            "m.emb", external_type_ir.source_location,
            "Only values '1' (bit) and '8' (byte) are allowed for the "
            "'addressable_unit_size' attribute")]
    ], attribute_checker.normalize_and_verify(external_ir))

  def test_rejects_duplicate_attribute(self):
    ir = _make_ir_from_emb("external Foo:\n"
                           "  [is_integer: true]\n"
                           "  [is_integer: true]\n")
    self.assertEqual([[
        error.error("m.emb", ir.module[0].type[0].attribute[1].source_location,
                    "Duplicate attribute 'is_integer'."),
        error.note("m.emb", ir.module[0].type[0].attribute[0].source_location,
                   "Original attribute"),
    ]], attribute_checker.normalize_and_verify(ir))

  def test_rejects_duplicate_default_attribute(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           '[$default byte_order: "LittleEndian"]\n')
    self.assertEqual(
        [[
            error.error("m.emb", ir.module[0].attribute[1].source_location,
                        "Duplicate attribute 'byte_order'."),
            error.note("m.emb", ir.module[0].attribute[0].source_location,
                       "Original attribute"),
        ]], attribute_checker.normalize_and_verify(ir))

  def test_rejects_unknown_attribute(self):
    ir = _make_ir_from_emb("[gibberish: true]\n")
    attr = ir.module[0].attribute[0]
    self.assertEqual([[
        error.error("m.emb", attr.name.source_location,
                    "Unknown attribute 'gibberish' on module 'm.emb'.")
    ]], attribute_checker.normalize_and_verify(ir))

  def test_rejects_non_constant_attribute(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           "struct Foo:\n"
                           "  [fixed_size_in_bits: field1]\n"
                           "  0 [+2]  UInt  field1\n")
    attr = ir.module[0].type[0].attribute[0]
    self.assertEqual(
        [[
            error.error(
                "m.emb", attr.value.source_location,
                "Attribute 'fixed_size_in_bits' must have a constant value.")
        ]],
        attribute_checker.normalize_and_verify(ir))

  def test_accepts_string_attribute(self):
    ir = _make_ir_from_emb('[(cpp) namespace: "foo"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))

  def test_rejects_wrong_type_for_string_attribute(self):
    ir = _make_ir_from_emb("[(cpp) namespace: 9]\n")
    attr = ir.module[0].attribute[0]
    self.assertEqual([[
        error.error("m.emb", attr.value.source_location,
                    "Attribute 'namespace' must have a string value.")
    ]], attribute_checker.normalize_and_verify(ir))

  def test_accepts_back_end_qualified_attribute(self):
    ir = _make_ir_from_emb('[(cpp) namespace: "abc"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))

  def test_rejects_attribute_missing_required_back_end_specifier(self):
    ir = _make_ir_from_emb('[namespace: "abc"]\n')
    attr = ir.module[0].attribute[0]
    self.assertEqual([[
        error.error("m.emb", attr.name.source_location,
                    "Unknown attribute 'namespace' on module 'm.emb'.")
    ]], attribute_checker.normalize_and_verify(ir))

  def test_rejects_attribute_with_wrong_back_end_specifier(self):
    ir = _make_ir_from_emb('[(c) namespace: "abc"]\n')
    attr = ir.module[0].attribute[0]
    self.assertEqual([[
        error.error("m.emb", attr.name.source_location,
                    "Unknown attribute '(c) namespace' on module 'm.emb'.")
    ]], attribute_checker.normalize_and_verify(ir))

  def test_rejects_emboss_internal_attribute_with_back_end_specifier(self):
    ir = _make_ir_from_emb('[(cpp) byte_order: "LittleEndian"]\n')
    attr = ir.module[0].attribute[0]
    self.assertEqual([[
        error.error("m.emb", attr.name.source_location,
                    "Unknown attribute '(cpp) byte_order' on module 'm.emb'.")
    ]], attribute_checker.normalize_and_verify(ir))

  def test_adds_byte_order_attributes_from_default(self):
    ir = _make_ir_from_emb('[$default byte_order: "BigEndian"]\n'
                           "struct Foo:\n"
                           "  0 [+2]  UInt  bar\n"
                           "  2 [+2]  UInt  baz\n"
                           '    [byte_order: "LittleEndian"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))
    byte_order_attr = ir_util.get_attribute(
        ir.module[0].type[0].structure.field[0].attribute, _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("BigEndian", byte_order_attr.string_constant.text)
    byte_order_attr = ir_util.get_attribute(
        ir.module[0].type[0].structure.field[1].attribute, _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("LittleEndian", byte_order_attr.string_constant.text)

  def test_adds_null_byte_order_attributes(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+1]  UInt      bar\n"
                           "  1 [+1]  UInt      baz\n"
                           '    [byte_order: "LittleEndian"]\n'
                           "  2 [+2]  UInt:8[]  baseball\n"
                           "  4 [+2]  UInt:8[]  bat\n"
                           '    [byte_order: "LittleEndian"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))
    structure = ir.module[0].type[0].structure
    byte_order_attr = ir_util.get_attribute(
        structure.field[0].attribute, _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("Null", byte_order_attr.string_constant.text)
    self.assertEqual(structure.field[0].source_location,
                     byte_order_attr.source_location)
    byte_order_attr = ir_util.get_attribute(structure.field[1].attribute,
                                            _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("LittleEndian", byte_order_attr.string_constant.text)
    byte_order_attr = ir_util.get_attribute(structure.field[2].attribute,
                                            _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("Null", byte_order_attr.string_constant.text)
    self.assertEqual(structure.field[2].source_location,
                     byte_order_attr.source_location)
    byte_order_attr = ir_util.get_attribute(structure.field[3].attribute,
                                            _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("LittleEndian", byte_order_attr.string_constant.text)

  def test_disallows_default_byte_order_on_field(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           "struct Foo:\n"
                           "  0 [+2]  UInt  bar\n"
                           '    [$default byte_order: "LittleEndian"]\n')
    default_byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", default_byte_order.name.source_location,
            "Attribute 'byte_order' may not be defaulted on struct field 'bar'."
        )]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_default_byte_order_on_bits(self):
    ir = _make_ir_from_emb("bits Foo:\n"
                           '  [$default byte_order: "LittleEndian"]\n'
                           "  0 [+2]  UInt  bar\n")
    default_byte_order = ir.module[0].type[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", default_byte_order.name.source_location,
            "Attribute 'byte_order' may not be defaulted on bits 'Foo'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_default_byte_order_on_enum(self):
    ir = _make_ir_from_emb("enum Foo:\n"
                           '  [$default byte_order: "LittleEndian"]\n'
                           "  BAR = 1\n")
    default_byte_order = ir.module[0].type[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", default_byte_order.name.source_location,
            "Attribute 'byte_order' may not be defaulted on enum 'Foo'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_adds_byte_order_from_scoped_default(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           "struct Foo:\n"
                           '  [$default byte_order: "BigEndian"]\n'
                           "  0 [+2]  UInt  bar\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))
    byte_order_attr = ir_util.get_attribute(
        ir.module[0].type[0].structure.field[0].attribute, _BYTE_ORDER)
    self.assertTrue(byte_order_attr.HasField("string_constant"))
    self.assertEqual("BigEndian", byte_order_attr.string_constant.text)

  def test_disallows_unknown_byte_order(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+2]  UInt  bar\n"
                           '    [byte_order: "NoEndian"]\n')
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'byte_order' must be 'BigEndian' or 'LittleEndian' or "
            "'Null'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_unknown_default_byte_order(self):
    ir = _make_ir_from_emb('[$default byte_order: "NoEndian"]\n')
    default_byte_order = ir.module[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", default_byte_order.value.source_location,
            "Attribute 'byte_order' must be 'BigEndian' or 'LittleEndian' or "
            "'Null'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_byte_order_on_non_byte_order_dependent_fields(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           '  [$default byte_order: "LittleEndian"]\n'
                           "  0 [+2]  UInt  uint\n"
                           "struct Bar:\n"
                           "  0 [+2]  Foo  foo\n"
                           '    [byte_order: "LittleEndian"]\n')
    byte_order = ir.module[0].type[1].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'byte_order' not allowed on field which is not byte "
            "order dependent.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_byte_order_on_virtual_field(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  let x = 10\n"
                           '    [byte_order: "LittleEndian"]\n')
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.name.source_location,
            "Unknown attribute 'byte_order' on virtual struct field 'x'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_null_byte_order_on_multibyte_fields(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+2]  UInt  uint\n"
                           '    [byte_order: "Null"]\n')
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'byte_order' may only be 'Null' for one-byte fields.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_null_byte_order_on_multibyte_array_elements(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+4]  UInt:16[]  uint\n"
                           '    [byte_order: "Null"]\n')
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'byte_order' may only be 'Null' for one-byte fields.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_requires_byte_order_on_byte_order_dependent_fields(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+2]  UInt  uint\n")
    field = ir.module[0].type[0].structure.field[0]
    self.assertEqual(
        [[error.error(
            "m.emb", field.source_location,
            "Attribute 'byte_order' required on field which is byte order "
            "dependent.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_unknown_text_output_attribute(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+2]  UInt  bar\n"
                           '    [text_output: "None"]\n')
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'text_output' must be 'Emit' or 'Skip'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_disallows_non_string_text_output_attribute(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+2]  UInt  bar\n"
                           "    [text_output: 0]\n")
    byte_order = ir.module[0].type[0].structure.field[0].attribute[0]
    self.assertEqual(
        [[error.error(
            "m.emb", byte_order.value.source_location,
            "Attribute 'text_output' must be 'Emit' or 'Skip'.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_allows_skip_text_output_attribute_on_physical_field(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+1]  UInt  bar\n"
                           '    [text_output: "Skip"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))

  def test_allows_skip_text_output_attribute_on_virtual_field(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  let x = 10\n"
                           '    [text_output: "Skip"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))

  def test_allows_emit_text_output_attribute_on_physical_field(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+1]  UInt  bar\n"
                           '    [text_output: "Emit"]\n')
    self.assertEqual([], attribute_checker.normalize_and_verify(ir))

  def test_adds_bit_addressable_unit_to_external(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [addressable_unit_size: 1]\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(external_ir))
    self.assertEqual(ir_pb2.TypeDefinition.BIT,
                     external_ir.module[0].type[0].addressable_unit)

  def test_adds_byte_addressable_unit_to_external(self):
    external_ir = _make_ir_from_emb("external Foo:\n"
                                    "  [addressable_unit_size: 8]\n")
    self.assertEqual([], attribute_checker.normalize_and_verify(external_ir))
    self.assertEqual(ir_pb2.TypeDefinition.BYTE,
                     external_ir.module[0].type[0].addressable_unit)

  def test_rejects_requires_using_array(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+4]  UInt:8[]  array\n"
                           "    [requires: this]\n")
    field_ir = ir.module[0].type[0].structure.field[0]
    self.assertEqual(
        [[error.error("m.emb", field_ir.attribute[0].value.source_location,
                      "Attribute 'requires' must have a boolean value.")]],
        attribute_checker.normalize_and_verify(ir))

  def test_rejects_requires_on_array(self):
    ir = _make_ir_from_emb("struct Foo:\n"
                           "  0 [+4]  UInt:8[]  array\n"
                           "    [requires: false]\n")
    field_ir = ir.module[0].type[0].structure.field[0]
    self.assertEqual(
        [[
            error.error("m.emb", field_ir.attribute[0].value.source_location,
                        "Attribute 'requires' is only allowed on integer, "
                        "enumeration, or boolean fields, not arrays."),
            error.note("m.emb", field_ir.type.source_location,
                       "Field type."),
        ]],
        error.filter_errors(attribute_checker.normalize_and_verify(ir)))

  def test_rejects_requires_on_struct(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           "struct Foo:\n"
                           "  0 [+4]  Bar  bar\n"
                           "    [requires: false]\n"
                           "struct Bar:\n"
                           "  0 [+4]  UInt  uint\n")
    field_ir = ir.module[0].type[0].structure.field[0]
    self.assertEqual(
        [[error.error("m.emb", field_ir.attribute[0].value.source_location,
                      "Attribute 'requires' is only allowed on integer, "
                      "enumeration, or boolean fields.")]],
        error.filter_errors(attribute_checker.normalize_and_verify(ir)))

  def test_rejects_requires_on_float(self):
    ir = _make_ir_from_emb('[$default byte_order: "LittleEndian"]\n'
                           "struct Foo:\n"
                           "  0 [+4]  Float  float\n"
                           "    [requires: false]\n")
    field_ir = ir.module[0].type[0].structure.field[0]
    self.assertEqual(
        [[error.error("m.emb", field_ir.attribute[0].value.source_location,
                      "Attribute 'requires' is only allowed on integer, "
                      "enumeration, or boolean fields.")]],
        error.filter_errors(attribute_checker.normalize_and_verify(ir)))


if __name__ == "__main__":
  unittest.main()