| """Helper library to traverse data emitted for Rust enums """ |
| from lldbsuite.test.lldbtest import * |
| |
| DISCRIMINANT_MEMBER_NAME = "$discr$" |
| VALUE_MEMBER_NAME = "value" |
| |
| |
| class RustEnumValue: |
| def __init__(self, value: lldb.SBValue): |
| self.value = value |
| |
| def getAllVariantTypes(self): |
| result = [] |
| for i in range(self._inner().GetNumChildren()): |
| result.append(self.getVariantByIndex(i).GetDisplayTypeName()) |
| return result |
| |
| def _inner(self) -> lldb.SBValue: |
| return self.value.GetChildAtIndex(0) |
| |
| def getVariantByIndex(self, index): |
| return ( |
| self._inner() |
| .GetChildAtIndex(index) |
| .GetChildMemberWithName(VALUE_MEMBER_NAME) |
| ) |
| |
| @staticmethod |
| def _getDiscriminantValueAsUnsigned(discr_sbvalue: lldb.SBValue): |
| byte_size = discr_sbvalue.GetType().GetByteSize() |
| error = lldb.SBError() |
| |
| # when discriminant is u16 Clang emits 'unsigned char' |
| # and LLDB seems to treat it as character type disalowing to call GetValueAsUnsigned |
| if byte_size == 1: |
| return discr_sbvalue.GetData().GetUnsignedInt8(error, 0) |
| elif byte_size == 2: |
| return discr_sbvalue.GetData().GetUnsignedInt16(error, 0) |
| elif byte_size == 4: |
| return discr_sbvalue.GetData().GetUnsignedInt32(error, 0) |
| elif byte_size == 8: |
| return discr_sbvalue.GetData().GetUnsignedInt64(error, 0) |
| else: |
| return discr_sbvalue.GetValueAsUnsigned() |
| |
| def getCurrentVariantIndex(self): |
| default_index = 0 |
| for i in range(self._inner().GetNumChildren()): |
| variant: lldb.SBValue = self._inner().GetChildAtIndex(i) |
| discr = variant.GetChildMemberWithName(DISCRIMINANT_MEMBER_NAME) |
| if discr.IsValid(): |
| discr_unsigned_value = RustEnumValue._getDiscriminantValueAsUnsigned( |
| discr |
| ) |
| if variant.GetName() == f"$variant${discr_unsigned_value}": |
| return discr_unsigned_value |
| else: |
| default_index = i |
| return default_index |
| |
| def getFields(self): |
| result = [] |
| for i in range(self._inner().GetNumChildren()): |
| type: lldb.SBType = self._inner().GetType() |
| result.append(type.GetFieldAtIndex(i).GetName()) |
| return result |
| |
| def getCurrentValue(self) -> lldb.SBValue: |
| return self.getVariantByIndex(self.getCurrentVariantIndex()) |
