private static ExpressionSyntax CreateEnumMemberValue(EnumDeclarationSyntax destinationOpt, IFieldSymbol enumMember)
{
if (!enumMember.HasConstantValue)
{
return(null);
}
if (enumMember.ConstantValue is not byte and
not sbyte and
not ushort and
not short and
not int and
not uint and
not long and
not ulong)
{
return(null);
}
var value = IntegerUtilities.ToInt64(enumMember.ConstantValue);
if (destinationOpt != null)
{
if (destinationOpt.Members.Count == 0)
{
if (value == 0)
{
return(null);
}
}
else
{
// Don't generate an initializer if no other members have them, and our value
// would be correctly inferred from our position.
if (destinationOpt.Members.Count == value &&
destinationOpt.Members.All(m => m.EqualsValue == null))
{
return(null);
}
// Existing members, try to stay consistent with their style.
var lastMember = destinationOpt.Members.LastOrDefault(m => m.EqualsValue != null);
if (lastMember != null)
{
var lastExpression = lastMember.EqualsValue.Value;
if (lastExpression.Kind() == SyntaxKind.LeftShiftExpression &&
IntegerUtilities.HasOneBitSet(value))
{
var binaryExpression = (BinaryExpressionSyntax)lastExpression;
if (binaryExpression.Left.Kind() == SyntaxKind.NumericLiteralExpression)
{
var numericLiteral = (LiteralExpressionSyntax)binaryExpression.Left;
if (numericLiteral.Token.ValueText == "1")
{
// The user is left shifting ones, stick with that pattern
var shiftValue = IntegerUtilities.LogBase2(value);
// Re-use the numericLiteral text so type suffixes match too
return(SyntaxFactory.BinaryExpression(
SyntaxKind.LeftShiftExpression,
SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression, SyntaxFactory.Literal(numericLiteral.Token.Text, 1)),
SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression, SyntaxFactory.Literal(shiftValue.ToString(), shiftValue))));
}
}
}
else if (lastExpression.IsKind(SyntaxKind.NumericLiteralExpression, out LiteralExpressionSyntax numericLiteral))
{
var numericToken = numericLiteral.Token;
var numericText = numericToken.ToString();
if (numericText.StartsWith("0x", StringComparison.OrdinalIgnoreCase))
{
// Hex
return(SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression,
SyntaxFactory.Literal(numericText.Substring(0, 2) + value.ToString("X"), value)));
}
else if (numericText.StartsWith("0b", StringComparison.OrdinalIgnoreCase))
{
return(SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression,
SyntaxFactory.Literal(numericText.Substring(0, 2) + Convert.ToString(value, 2), value)));
}
}
}
}
}
var namedType = enumMember.Type as INamedTypeSymbol;
var underlyingType = namedType?.EnumUnderlyingType;
return(ExpressionGenerator.GenerateNonEnumValueExpression(
underlyingType,
enumMember.ConstantValue,
canUseFieldReference: true));
}
private static ExpressionSyntax CreateEnumMemberValue(EnumDeclarationSyntax destinationOpt, IFieldSymbol enumMember)
{
var valueOpt = enumMember.ConstantValue is IConvertible
? (long?)IntegerUtilities.ToInt64(enumMember.ConstantValue)
: null;
if (valueOpt == null)
{
return(null);
}
var value = valueOpt.Value;
if (destinationOpt != null)
{
if (destinationOpt.Members.Count == 0)
{
if (value == 0)
{
return(null);
}
}
else
{
// Don't generate an initializer if no other members have them, and our value
// would be correctly inferred from our position.
if (destinationOpt.Members.Count == value &&
destinationOpt.Members.All(m => m.EqualsValue == null))
{
return(null);
}
// Existing members, try to stay consistent with their style.
var lastMember = destinationOpt.Members.LastOrDefault(m => m.EqualsValue != null);
if (lastMember != null)
{
var lastExpression = lastMember.EqualsValue.Value;
if (lastExpression.CSharpKind() == SyntaxKind.LeftShiftExpression &&
IntegerUtilities.HasOneBitSet(value))
{
var binaryExpression = (BinaryExpressionSyntax)lastExpression;
if (binaryExpression.Left.CSharpKind() == SyntaxKind.NumericLiteralExpression)
{
var numericLiteral = (LiteralExpressionSyntax)binaryExpression.Left;
if (numericLiteral.Token.ValueText == "1")
{
// The user is left shifting ones, stick with that pattern
var shiftValue = IntegerUtilities.LogBase2(value);
return(SyntaxFactory.BinaryExpression(
SyntaxKind.LeftShiftExpression,
SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression, SyntaxFactory.Literal("1", 1)),
SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression, SyntaxFactory.Literal(shiftValue.ToString(), shiftValue))));
}
}
}
else if (lastExpression.CSharpKind() == SyntaxKind.NumericLiteralExpression)
{
var numericLiteral = (LiteralExpressionSyntax)lastExpression;
var numericToken = numericLiteral.Token;
var numericText = numericToken.ToString();
if (numericText.StartsWith("0x") || numericText.StartsWith("0X"))
{
// Hex
return(SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression,
SyntaxFactory.Literal(numericText.Substring(0, 2) + value.ToString("X"), value)));
}
}
}
}
}
var namedType = enumMember.Type as INamedTypeSymbol;
var underlyingType = namedType != null ? namedType.EnumUnderlyingType : null;
return(ExpressionGenerator.GenerateNonEnumValueExpression(
underlyingType,
enumMember.ConstantValue,
canUseFieldReference: true));
}