/// <summary>
/// Get the individual words in the parameter name. This way we can generate
/// appropriate field/property names based on the user's preference.
/// </summary>
private List <string> GetParameterWordParts(IParameterSymbol parameter)
{
using (var breaks = StringBreaker.BreakIntoWordParts(parameter.Name))
{
return(CreateWords(breaks, parameter.Name));
}
}
internal static ImmutableArray <IEnumerable <string> > GetBaseNames(ITypeSymbol type)
{
var baseName = TryRemoveInterfacePrefix(type);
var breaks = StringBreaker.BreakIntoWordParts(baseName);
return(GetInterleavedPatterns(breaks, baseName));
}
public static string GetLocalName(this INamedTypeSymbol containingType)
{
var parts = StringBreaker.BreakIntoWordParts(containingType.Name);
for (var i = parts.Count - 1; i >= 0; i--)
{
var p = parts[i];
if (char.IsLetter(containingType.Name[p.Start]))
{
return(containingType.Name.Substring(p.Start, p.Length).ToCamelCase());
}
}
return("v");
}
private static ImmutableArray <SyntaxNode> CreateEqualsMethodStatements(
SyntaxGenerator factory,
Compilation compilation,
INamedTypeSymbol containingType,
IEnumerable <ISymbol> members,
CancellationToken cancellationToken)
{
var iequatableType = compilation.GetTypeByMetadataName("System.IEquatable`1");
var statements = ArrayBuilder <SyntaxNode> .GetInstance();
// Come up with a good name for the local variable we're going to compare against.
// For example, if the class name is "CustomerOrder" then we'll generate:
//
// var order = obj as CustomerOrder;
var parts = StringBreaker.BreakIntoWordParts(containingType.Name);
var localName = "v";
for (var i = parts.Count - 1; i >= 0; i--)
{
var p = parts[i];
if (char.IsLetter(containingType.Name[p.Start]))
{
localName = containingType.Name.Substring(p.Start, p.Length).ToCamelCase();
break;
}
}
var localNameExpression = factory.IdentifierName(localName);
var objNameExpression = factory.IdentifierName(ObjName);
// These will be all the expressions that we'll '&&' together inside the final
// return statement of 'Equals'.
var expressions = new List <SyntaxNode>();
if (containingType.IsValueType)
{
// If we're a value type, then we need an is-check first to make sure
// the object is our type:
//
// if (!(obj is MyType))
// {
// return false;
// }
var ifStatement = factory.IfStatement(
factory.LogicalNotExpression(
factory.IsTypeExpression(
objNameExpression,
containingType)),
new[] { factory.ReturnStatement(factory.FalseLiteralExpression()) });
// Next, we cast the argument to our type:
//
// var myType = (MyType)obj;
var localDeclaration = factory.LocalDeclarationStatement(localName, factory.CastExpression(containingType, objNameExpression));
statements.Add(ifStatement);
statements.Add(localDeclaration);
}
else
{
// It's not a value type, we can just use "as" to test the parameter is the right type:
//
// var myType = obj as MyType;
var localDeclaration = factory.LocalDeclarationStatement(localName, factory.TryCastExpression(objNameExpression, containingType));
statements.Add(localDeclaration);
// Ensure that the parameter we got was not null (which also ensures the 'as' test
// succeeded):
//
// myType != null
expressions.Add(factory.ReferenceNotEqualsExpression(localNameExpression, factory.NullLiteralExpression()));
if (HasExistingBaseEqualsMethod(containingType, cancellationToken))
{
// If we're overriding something that also provided an overridden 'Equals',
// then ensure the base type thinks it is equals as well.
//
// base.Equals(obj)
expressions.Add(factory.InvocationExpression(
factory.MemberAccessExpression(
factory.BaseExpression(),
factory.IdentifierName(EqualsName)),
objNameExpression));
}
}
// Now, iterate over all the supplied members and ensure that our instance
// and the parameter think they are equals. Specialize how we do this for
// common types. Fall-back to EqualityComparer<SType>.Default.Equals for
// everything else.
foreach (var member in members)
{
var symbolNameExpression = factory.IdentifierName(member.Name);
var thisSymbol = factory.MemberAccessExpression(factory.ThisExpression(), symbolNameExpression)
.WithAdditionalAnnotations(Simplification.Simplifier.Annotation);
var otherSymbol = factory.MemberAccessExpression(localNameExpression, symbolNameExpression);
var memberType = member.GetSymbolType();
if (IsPrimitiveValueType(memberType))
{
// If we have one of the well known primitive types, then just use '==' to compare
// the values.
//
// this.a == other.a
expressions.Add(factory.ValueEqualsExpression(thisSymbol, otherSymbol));
continue;
}
var valueIEquatable = memberType?.IsValueType == true && ImplementsIEquatable(memberType, iequatableType);
if (valueIEquatable || memberType?.IsTupleType == true)
{
// If it's a value type and implements IEquatable<T>, Or if it's a tuple, then
// just call directly into .Equals. This keeps the code simple and avoids an
// unnecessary null check.
//
// this.a.Equals(other.a)
expressions.Add(factory.InvocationExpression(
factory.MemberAccessExpression(thisSymbol, nameof(object.Equals)),
otherSymbol));
continue;
}
// Otherwise call EqualityComparer<SType>.Default.Equals(this.a, other.a).
// This will do the appropriate null checks as well as calling directly
// into IEquatable<T>.Equals implementations if available.
expressions.Add(factory.InvocationExpression(
factory.MemberAccessExpression(
GetDefaultEqualityComparer(factory, compilation, member),
factory.IdentifierName(EqualsName)),
thisSymbol,
otherSymbol));
}
// Now combine all the comparison expressions together into one final statement like:
//
// return myType != null &&
// base.Equals(obj) &&
// this.S1 == myType.S1;
statements.Add(factory.ReturnStatement(
expressions.Aggregate(factory.LogicalAndExpression)));
return(statements.ToImmutableAndFree());
}
private static IList <SyntaxNode> CreateEqualsMethodStatements(
ISyntaxFactoryService factory,
Compilation compilation,
INamedTypeSymbol containingType,
IEnumerable <ISymbol> members,
CancellationToken cancellationToken)
{
var statements = new List <SyntaxNode>();
var parts = StringBreaker.BreakIntoWordParts(containingType.Name);
string localName = "v";
for (int i = parts.Count - 1; i >= 0; i--)
{
var p = parts[i];
if (char.IsLetter(containingType.Name[p.Start]))
{
localName = containingType.Name.Substring(p.Start, p.Length).ToCamelCase();
break;
}
}
var localNameExpression = factory.CreateIdentifierName(localName);
var objNameExpression = factory.CreateIdentifierName(ObjName);
var expressions = new List <SyntaxNode>();
if (containingType.IsValueType)
{
#if false
if (!(obj is MyType))
{
return(false);
}
#endif
var ifStatement = factory.CreateIfStatement(
factory.CreateLogicalNotExpression(
factory.CreateIsExpression(
objNameExpression,
containingType)),
new[] { factory.CreateReturnStatement(factory.CreateFalseExpression()) });
#if false
var myType = (MyType)obj;
#endif
var localDeclaration = factory.CreateLocalDeclarationStatement(
factory.CreateVariableDeclarator(localName, factory.CreateCastExpression(containingType, objNameExpression)));
statements.Add(ifStatement);
statements.Add(localDeclaration);
}
else
{
#if false
var myType = obj as MyType;
#endif
var localDeclaration = factory.CreateLocalDeclarationStatement(
factory.CreateVariableDeclarator(localName, factory.CreateAsExpression(objNameExpression, containingType)));
statements.Add(localDeclaration);
#if false
myType != null
#endif
expressions.Add(factory.CreateReferenceNotEqualsExpression(localNameExpression, factory.CreateNullExpression()));
if (HasExistingBaseEqualsMethod(containingType, cancellationToken))
{
#if false
base.Equals(obj)
#endif
expressions.Add(factory.CreateInvocationExpression(
factory.CreateMemberAccessExpression(
factory.CreateBaseExpression(),
factory.CreateIdentifierName(EqualsName)),
objNameExpression));
}
}
foreach (var member in members)
{
var symbolNameExpression = factory.CreateIdentifierName(member.Name);
var thisSymbol = factory.CreateMemberAccessExpression(factory.CreateThisExpression(), symbolNameExpression).WithAdditionalAnnotations(Simplification.Simplifier.Annotation);
var otherSymbol = factory.CreateMemberAccessExpression(localNameExpression, symbolNameExpression);
#if false
EqualityComparer <SType> .Default.Equals(this.S1, myType.S1)
#endif
var expression =
factory.CreateInvocationExpression(
factory.CreateMemberAccessExpression(
GetDefaultEqualityComparer(factory, compilation, member),
factory.CreateIdentifierName(EqualsName)),
thisSymbol,
otherSymbol);
expressions.Add(expression);
}
#if false
return(myType != null && base.Equals(obj) && EqualityComparer <int> .Default.Equals(this.S1, myType.S1) &&...);
#endif
statements.Add(factory.CreateReturnStatement(
expressions.Aggregate(factory.CreateLogicalAndExpression)));
return(statements);
}
private static IList <string> BreakIntoWordParts(string identifier)
{
return(PartListToSubstrings(identifier, StringBreaker.BreakIntoWordParts(identifier)));
}
/// <summary> /// Get the individual words in the parameter name. This way we can generate /// appropriate field/property names based on the user's preference. /// </summary> private List <string> GetParameterWordParts(IParameterSymbol parameter) => CreateWords(StringBreaker.BreakIntoWordParts(parameter.Name), parameter.Name);