protected BoundExpression ConvertCaseExpression(CSharpSyntaxNode node, BoundExpression caseExpression, Binder sectionBinder, out ConstantValue constantValueOpt, BindingDiagnosticBag diagnostics, bool isGotoCaseExpr = false)
{
bool hasErrors = false;
if (isGotoCaseExpr)
{
// SPEC VIOLATION for Dev10 COMPATIBILITY:
// Dev10 compiler violates the SPEC comment below:
// "if the constant-expression is not implicitly convertible (§6.1) to
// the governing type of the nearest enclosing switch statement,
// a compile-time error occurs"
// If there is no implicit conversion from gotoCaseExpression to switchGoverningType,
// but there exists an explicit conversion, Dev10 compiler generates a warning "WRN_GotoCaseShouldConvert"
// instead of an error. See test "CS0469_NoImplicitConversionWarning".
CompoundUseSiteInfo <AssemblySymbol> useSiteInfo = GetNewCompoundUseSiteInfo(diagnostics);
Conversion conversion = Conversions.ClassifyConversionFromExpression(caseExpression, SwitchGoverningType, ref useSiteInfo);
diagnostics.Add(node, useSiteInfo);
if (!conversion.IsValid)
{
GenerateImplicitConversionError(diagnostics, node, conversion, caseExpression, SwitchGoverningType);
hasErrors = true;
}
else if (!conversion.IsImplicit)
{
diagnostics.Add(ErrorCode.WRN_GotoCaseShouldConvert, node.Location, SwitchGoverningType);
hasErrors = true;
}
caseExpression = CreateConversion(caseExpression, conversion, SwitchGoverningType, diagnostics);
}
return(ConvertPatternExpression(SwitchGoverningType, node, caseExpression, out constantValueOpt, hasErrors, diagnostics));
}
internal static bool CheckFeatureAvailability(
this MessageID feature,
BindingDiagnosticBag diagnostics,
SyntaxNode syntax,
Location?location = null)
{
var diag = GetFeatureAvailabilityDiagnosticInfo(feature, (CSharpParseOptions)syntax.SyntaxTree.Options);
if (diag is object)
{
diagnostics.Add(diag, location ?? syntax.GetLocation());
return(false);
}
return(true);
}
internal static bool CheckFeatureAvailability(
this MessageID feature,
BindingDiagnosticBag diagnostics,
Compilation compilation,
Location location
)
{
if (
GetFeatureAvailabilityDiagnosticInfo(feature, (CSharpCompilation)compilation) is
{ } diagInfo
)
{
diagnostics.Add(diagInfo, location);
return(false);
}
return(true);
}
/// <summary>
/// Checks that the Awaiter implements System.Runtime.CompilerServices.INotifyCompletion.
/// </summary>
/// <remarks>
/// Spec 7.7.7.1:
/// An Awaiter A implements the interface System.Runtime.CompilerServices.INotifyCompletion.
/// </remarks>
private bool AwaiterImplementsINotifyCompletion(TypeSymbol awaiterType, SyntaxNode node, BindingDiagnosticBag diagnostics)
{
var INotifyCompletion = GetWellKnownType(WellKnownType.System_Runtime_CompilerServices_INotifyCompletion, diagnostics, node);
CompoundUseSiteInfo <AssemblySymbol> useSiteInfo = GetNewCompoundUseSiteInfo(diagnostics);
var conversion = this.Conversions.ClassifyImplicitConversionFromType(awaiterType, INotifyCompletion, ref useSiteInfo);
if (!conversion.IsImplicit)
{
diagnostics.Add(node, useSiteInfo);
Error(diagnostics, ErrorCode.ERR_DoesntImplementAwaitInterface, node, awaiterType, INotifyCompletion);
return(false);
}
Debug.Assert(conversion.IsValid);
return(true);
}
private static bool ReportQueryInferenceFailedSelectMany(
FromClauseSyntax fromClause,
string methodName,
BoundExpression receiver,
AnalyzedArguments arguments,
ImmutableArray <Symbol> symbols,
BindingDiagnosticBag diagnostics
)
{
Debug.Assert(methodName == "SelectMany");
// Estimate the return type of Select's lambda argument
BoundExpression arg = arguments.Argument(arguments.IsExtensionMethodInvocation ? 1 : 0);
TypeSymbol type = null;
if (arg.Kind == BoundKind.UnboundLambda)
{
var unbound = (UnboundLambda)arg;
foreach (var t in unbound.Data.InferredReturnTypes())
{
if (!t.IsErrorType())
{
type = t;
break;
}
}
}
if ((object)type == null || type.IsErrorType())
{
return(false);
}
TypeSymbol receiverType = receiver?.Type;
diagnostics.Add(
new DiagnosticInfoWithSymbols(
ErrorCode.ERR_QueryTypeInferenceFailedSelectMany,
new object[] { type, receiverType, methodName },
symbols
),
fromClause.Expression.Location
);
return(true);
}
private ImmutableArray <Symbol> BindTypeCref(TypeCrefSyntax syntax, out Symbol?ambiguityWinner, BindingDiagnosticBag diagnostics)
{
NamespaceOrTypeSymbol result = BindNamespaceOrTypeSymbolInCref(syntax.Type);
// NOTE: we don't have to worry about the case where a non-error type is constructed
// with erroneous type arguments, because only MemberCrefs have type arguments -
// all other crefs only have type parameters.
if (result.Kind == SymbolKind.ErrorType)
{
var noTrivia = syntax.WithLeadingTrivia(null).WithTrailingTrivia(null);
diagnostics.Add(ErrorCode.WRN_BadXMLRef, syntax.Location, noTrivia.ToFullString());
}
// We'll never have more than one type, but it is conceivable that result could
// be an ExtendedErrorTypeSymbol with multiple candidates.
ambiguityWinner = null;
return(ImmutableArray.Create <Symbol>(result));
}
internal override BoundStatement BindSwitchStatementCore(SwitchStatementSyntax node, Binder originalBinder, BindingDiagnosticBag diagnostics)
{
Debug.Assert(SwitchSyntax.Equals(node));
if (node.Sections.Count == 0)
{
diagnostics.Add(ErrorCode.WRN_EmptySwitch, node.OpenBraceToken.GetLocation());
}
// Bind switch expression and set the switch governing type.
BoundExpression boundSwitchGoverningExpression = SwitchGoverningExpression;
diagnostics.AddRange(SwitchGoverningDiagnostics, allowMismatchInDependencyAccumulation: true);
ImmutableArray <BoundSwitchSection> switchSections = BindSwitchSections(originalBinder, diagnostics, out BoundSwitchLabel defaultLabel);
ImmutableArray <LocalSymbol> locals = GetDeclaredLocalsForScope(node);
ImmutableArray <LocalFunctionSymbol> functions = GetDeclaredLocalFunctionsForScope(node);
BoundDecisionDag decisionDag = DecisionDagBuilder.CreateDecisionDagForSwitchStatement(
compilation: this.Compilation,
syntax: node,
switchGoverningExpression: boundSwitchGoverningExpression,
switchSections: switchSections,
// If there is no explicit default label, the default action is to break out of the switch
defaultLabel: defaultLabel?.Label ?? BreakLabel,
diagnostics);
// Report subsumption errors, but ignore the input's constant value for that.
CheckSwitchErrors(node, boundSwitchGoverningExpression, ref switchSections, decisionDag, diagnostics);
// When the input is constant, we use that to reshape the decision dag that is returned
// so that flow analysis will see that some of the cases may be unreachable.
decisionDag = decisionDag.SimplifyDecisionDagIfConstantInput(boundSwitchGoverningExpression);
return(new BoundSwitchStatement(
syntax: node,
expression: boundSwitchGoverningExpression,
innerLocals: locals,
innerLocalFunctions: functions,
switchSections: switchSections,
defaultLabel: defaultLabel,
breakLabel: this.BreakLabel,
reachabilityDecisionDag: decisionDag));
}
internal bool ReportUnsafeIfNotAllowed(
SyntaxNode node,
BindingDiagnosticBag diagnostics,
TypeSymbol sizeOfTypeOpt = null
)
{
Debug.Assert(
(node.Kind() == SyntaxKind.SizeOfExpression) == ((object)sizeOfTypeOpt != null),
"Should have a type for (only) sizeof expressions."
);
var diagnosticInfo = GetUnsafeDiagnosticInfo(sizeOfTypeOpt);
if (diagnosticInfo == null)
{
return(false);
}
diagnostics.Add(new CSDiagnostic(diagnosticInfo, node.Location));
return(true);
}
private TypeSymbol InferResultType(ImmutableArray <BoundSwitchExpressionArm> switchCases, BindingDiagnosticBag diagnostics)
{
var seenTypes = Symbols.SpecializedSymbolCollections.GetPooledSymbolHashSetInstance <TypeSymbol>();
var typesInOrder = ArrayBuilder <TypeSymbol> .GetInstance();
foreach (var @case in switchCases)
{
var type = @case.Value.Type;
if (type is object && seenTypes.Add(type))
{
typesInOrder.Add(type);
}
}
seenTypes.Free();
CompoundUseSiteInfo <AssemblySymbol> useSiteInfo = GetNewCompoundUseSiteInfo(diagnostics);
var commonType = BestTypeInferrer.GetBestType(typesInOrder, Conversions, ref useSiteInfo);
typesInOrder.Free();
// We've found a candidate common type among those arms that have a type. Also check that every arm's
// expression (even those without a type) can be converted to that type.
if (commonType is object)
{
foreach (var @case in switchCases)
{
if (!this.Conversions.ClassifyImplicitConversionFromExpression(@case.Value, commonType, ref useSiteInfo).Exists)
{
commonType = null;
break;
}
}
}
diagnostics.Add(SwitchExpressionSyntax, useSiteInfo);
return(commonType);
}
internal RangeVariableSymbol AddRangeVariable(
Binder binder,
SyntaxToken identifier,
BindingDiagnosticBag diagnostics
)
{
string name = identifier.ValueText;
var result = new RangeVariableSymbol(
name,
binder.ContainingMemberOrLambda,
identifier.GetLocation()
);
bool error = false;
foreach (var existingRangeVariable in allRangeVariables.Keys)
{
if (existingRangeVariable.Name == name)
{
diagnostics.Add(
ErrorCode.ERR_QueryDuplicateRangeVariable,
identifier.GetLocation(),
name
);
error = true;
}
}
if (!error)
{
var collisionDetector = new LocalScopeBinder(binder);
collisionDetector.ValidateDeclarationNameConflictsInScope(result, diagnostics);
}
allRangeVariables.Add(result, ArrayBuilder <string> .GetInstance());
return(result);
}
private bool CheckSwitchExpressionExhaustive(
SwitchExpressionSyntax node,
BoundExpression boundInputExpression,
ImmutableArray <BoundSwitchExpressionArm> switchArms,
out BoundDecisionDag decisionDag,
out LabelSymbol defaultLabel,
BindingDiagnosticBag diagnostics)
{
defaultLabel = new GeneratedLabelSymbol("default");
decisionDag = DecisionDagBuilder.CreateDecisionDagForSwitchExpression(this.Compilation, node, boundInputExpression, switchArms, defaultLabel, diagnostics);
var reachableLabels = decisionDag.ReachableLabels;
bool hasErrors = false;
foreach (BoundSwitchExpressionArm arm in switchArms)
{
hasErrors |= arm.HasErrors;
if (!hasErrors && !reachableLabels.Contains(arm.Label))
{
diagnostics.Add(ErrorCode.ERR_SwitchArmSubsumed, arm.Pattern.Syntax.Location);
}
}
if (!reachableLabels.Contains(defaultLabel))
{
// switch expression is exhaustive; no default label needed.
defaultLabel = null;
return(false);
}
if (hasErrors)
{
return(true);
}
// We only report exhaustive warnings when the default label is reachable through some series of
// tests that do not include a test in which the value is known to be null. Handling paths with
// nulls is the job of the nullable walker.
bool wasAcyclic = TopologicalSort.TryIterativeSort <BoundDecisionDagNode>(new[] { decisionDag.RootNode }, nonNullSuccessors, out var nodes);
// Since decisionDag.RootNode is acyclic by construction, its subset of nodes sorted here cannot be cyclic
Debug.Assert(wasAcyclic);
foreach (var n in nodes)
{
if (n is BoundLeafDecisionDagNode leaf && leaf.Label == defaultLabel)
{
var samplePattern = PatternExplainer.SamplePatternForPathToDagNode(
BoundDagTemp.ForOriginalInput(boundInputExpression), nodes, n, nullPaths: false, out bool requiresFalseWhenClause, out bool unnamedEnumValue);
ErrorCode warningCode =
requiresFalseWhenClause ? ErrorCode.WRN_SwitchExpressionNotExhaustiveWithWhen :
unnamedEnumValue ? ErrorCode.WRN_SwitchExpressionNotExhaustiveWithUnnamedEnumValue :
ErrorCode.WRN_SwitchExpressionNotExhaustive;
diagnostics.Add(
warningCode,
node.SwitchKeyword.GetLocation(),
samplePattern);
return(true);
}
}
return(false);
ImmutableArray <BoundDecisionDagNode> nonNullSuccessors(BoundDecisionDagNode n)
{
switch (n)
{
case BoundTestDecisionDagNode p:
switch (p.Test)
{
case BoundDagNonNullTest t: // checks that the input is not null
return(ImmutableArray.Create(p.WhenTrue));
case BoundDagExplicitNullTest t: // checks that the input is null
return(ImmutableArray.Create(p.WhenFalse));
default:
return(BoundDecisionDag.Successors(n));
}
default:
return(BoundDecisionDag.Successors(n));
}
}
}
private BoundExpression BindAnonymousObjectCreation(AnonymousObjectCreationExpressionSyntax node, BindingDiagnosticBag diagnostics)
{
// prepare
var initializers = node.Initializers;
int fieldCount = initializers.Count;
bool hasError = false;
// bind field initializers
BoundExpression[] boundExpressions = new BoundExpression[fieldCount];
AnonymousTypeField[] fields = new AnonymousTypeField[fieldCount];
CSharpSyntaxNode[] fieldSyntaxNodes = new CSharpSyntaxNode[fieldCount];
// WARNING: Note that SemanticModel.GetDeclaredSymbol for field initializer node relies on
// the fact that the order of properties in anonymous type template corresponds
// 1-to-1 to the appropriate filed initializer syntax nodes; This means such
// correspondence must be preserved all the time including erroneous scenarios
// set of names already used
var uniqueFieldNames = PooledHashSet <string> .GetInstance();
for (int i = 0; i < fieldCount; i++)
{
AnonymousObjectMemberDeclaratorSyntax fieldInitializer = initializers[i];
NameEqualsSyntax?nameEquals = fieldInitializer.NameEquals;
ExpressionSyntax expression = fieldInitializer.Expression;
SyntaxToken nameToken = default(SyntaxToken);
if (nameEquals != null)
{
nameToken = nameEquals.Name.Identifier;
}
else
{
if (!IsAnonymousTypeMemberExpression(expression))
{
hasError = true;
diagnostics.Add(ErrorCode.ERR_InvalidAnonymousTypeMemberDeclarator, expression.GetLocation());
}
nameToken = expression.ExtractAnonymousTypeMemberName();
}
hasError |= expression.HasErrors;
boundExpressions[i] = BindRValueWithoutTargetType(expression, diagnostics);
// check the name to be unique
string?fieldName = null;
if (nameToken.Kind() == SyntaxKind.IdentifierToken)
{
fieldName = nameToken.ValueText;
if (!uniqueFieldNames.Add(fieldName !))
{
// name duplication
Error(diagnostics, ErrorCode.ERR_AnonymousTypeDuplicatePropertyName, fieldInitializer);
hasError = true;
fieldName = null;
}
}
else
{
// there is something wrong with field's name
hasError = true;
}
// calculate the expression's type and report errors if needed
TypeSymbol fieldType = GetAnonymousTypeFieldType(boundExpressions[i], fieldInitializer, diagnostics, ref hasError);
// build anonymous type field descriptor
fieldSyntaxNodes[i] = (nameToken.Kind() == SyntaxKind.IdentifierToken) ? (CSharpSyntaxNode)nameToken.Parent ! : fieldInitializer;
fields[i] = new AnonymousTypeField(
fieldName == null ? "$" + i.ToString() : fieldName,
fieldSyntaxNodes[i].Location,
TypeWithAnnotations.Create(fieldType),
RefKind.None,
DeclarationScope.Unscoped);
// NOTE: ERR_InvalidAnonymousTypeMemberDeclarator (CS0746) would be generated by parser if needed
}
uniqueFieldNames.Free();
// Create anonymous type
AnonymousTypeManager manager = this.Compilation.AnonymousTypeManager;
AnonymousTypeDescriptor descriptor = new AnonymousTypeDescriptor(fields.AsImmutableOrNull(), node.NewKeyword.GetLocation());
NamedTypeSymbol anonymousType = manager.ConstructAnonymousTypeSymbol(descriptor);
// declarators - bound nodes created for providing semantic info
// on anonymous type fields having explicitly specified name
ArrayBuilder <BoundAnonymousPropertyDeclaration> declarators =
ArrayBuilder <BoundAnonymousPropertyDeclaration> .GetInstance();
for (int i = 0; i < fieldCount; i++)
{
NameEqualsSyntax?explicitName = initializers[i].NameEquals;
if (explicitName != null)
{
AnonymousTypeField field = fields[i];
if (field.Name != null)
{
// get property symbol and create a bound property declaration node
foreach (var symbol in anonymousType.GetMembers(field.Name))
{
if (symbol.Kind == SymbolKind.Property)
{
declarators.Add(new BoundAnonymousPropertyDeclaration(fieldSyntaxNodes[i], (PropertySymbol)symbol, field.Type));
break;
}
}
}
}
}
// check if anonymous object creation is allowed in this context
if (!this.IsAnonymousTypesAllowed())
{
Error(diagnostics, ErrorCode.ERR_AnonymousTypeNotAvailable, node.NewKeyword);
hasError = true;
}
// Finally create a bound node
return(new BoundAnonymousObjectCreationExpression(
node,
anonymousType.InstanceConstructors[0],
boundExpressions.AsImmutableOrNull(),
declarators.ToImmutableAndFree(),
anonymousType,
hasError));
}
private BoundExpression SelectField(
SimpleNameSyntax node,
BoundExpression receiver,
string name,
BindingDiagnosticBag diagnostics
)
{
var receiverType = receiver.Type as NamedTypeSymbol;
if ((object)receiverType == null || !receiverType.IsAnonymousType)
{
// We only construct transparent query variables using anonymous types, so if we're trying to navigate through
// some other type, we must have some query API where the types don't match up as expected.
var info = new CSDiagnosticInfo(
ErrorCode.ERR_UnsupportedTransparentIdentifierAccess,
name,
receiver.ExpressionSymbol ?? receiverType
);
if (receiver.Type?.IsErrorType() != true)
{
Error(diagnostics, info, node);
}
return(new BoundBadExpression(
node,
LookupResultKind.Empty,
ImmutableArray.Create <Symbol>(receiver.ExpressionSymbol),
ImmutableArray.Create(BindToTypeForErrorRecovery(receiver)),
new ExtendedErrorTypeSymbol(this.Compilation, "", 0, info)
));
}
LookupResult lookupResult = LookupResult.GetInstance();
LookupOptions options = LookupOptions.MustBeInstance;
CompoundUseSiteInfo <AssemblySymbol> useSiteInfo = GetNewCompoundUseSiteInfo(
diagnostics
);
LookupMembersWithFallback(
lookupResult,
receiver.Type,
name,
0,
ref useSiteInfo,
basesBeingResolved: null,
options: options
);
diagnostics.Add(node, useSiteInfo);
var result = BindMemberOfType(
node,
node,
name,
0,
indexed: false,
receiver,
default(SeparatedSyntaxList <TypeSyntax>),
default(ImmutableArray <TypeWithAnnotations>),
lookupResult,
BoundMethodGroupFlags.None,
diagnostics
);
lookupResult.Free();
return(result);
}
/// <summary>
/// Given a list of viable lookup results (based on the name, arity, and containing symbol),
/// attempt to select one.
/// </summary>
private ImmutableArray <Symbol> ProcessCrefMemberLookupResults(
ImmutableArray <Symbol> symbols,
int arity,
MemberCrefSyntax memberSyntax,
TypeArgumentListSyntax?typeArgumentListSyntax,
BaseCrefParameterListSyntax?parameterListSyntax,
out Symbol?ambiguityWinner,
BindingDiagnosticBag diagnostics)
{
Debug.Assert(!symbols.IsEmpty);
if (parameterListSyntax == null)
{
return(ProcessParameterlessCrefMemberLookupResults(symbols, arity, memberSyntax, typeArgumentListSyntax, out ambiguityWinner, diagnostics));
}
ArrayBuilder <Symbol> candidates = ArrayBuilder <Symbol> .GetInstance();
GetCrefOverloadResolutionCandidates(symbols, arity, typeArgumentListSyntax, candidates);
ImmutableArray <ParameterSymbol> parameterSymbols = BindCrefParameters(parameterListSyntax, diagnostics);
ImmutableArray <Symbol> results = PerformCrefOverloadResolution(candidates, parameterSymbols, arity, memberSyntax, out ambiguityWinner, diagnostics);
candidates.Free();
// NOTE: This diagnostic is just a hint that might help fix a broken cref, so don't do
// any work unless there are no viable candidates.
if (results.Length == 0)
{
for (int i = 0; i < parameterSymbols.Length; i++)
{
if (ContainsNestedTypeOfUnconstructedGenericType(parameterSymbols[i].Type))
{
// This warning is new in Roslyn, because our better-defined semantics for
// cref lookup disallow some things that were possible in dev12.
//
// Consider the following code:
//
// public class C<T>
// {
// public class Inner { }
//
// public void M(Inner i) { }
//
// /// <see cref="M"/>
// /// <see cref="C{T}.M"/>
// /// <see cref="C{Q}.M"/>
// /// <see cref="C{Q}.M(C{Q}.Inner)"/>
// /// <see cref="C{Q}.M(Inner)"/> // WRN_UnqualifiedNestedTypeInCref
// public void N() { }
// }
//
// Dev12 binds all of the crefs as "M:C`1.M(C{`0}.Inner)".
// Roslyn accepts all but the last. The issue is that the context for performing
// the lookup is not C<Q>, but C<T>. Consequently, Inner binds to C<T>.Inner and
// then overload resolution fails because C<T>.Inner does not match C<Q>.Inner,
// the parameter type of C<Q>.M. Since we could not agree that the old behavior
// was desirable (other than for backwards compatibility) and since mimicking it
// would have been expensive, we settled on introducing a new warning that at
// least hints to the user how then can work around the issue (i.e. by qualifying
// Inner as C{Q}.Inner). Additional details are available in DevDiv #743425.
//
// CONSIDER: We could actually put the qualified form in the warning message,
// but that would probably just make it more frustrating (i.e. if the compiler
// knows exactly what I mean, why do I have to type it).
//
// NOTE: This is not a great location (whole parameter instead of problematic type),
// but it's better than nothing.
diagnostics.Add(ErrorCode.WRN_UnqualifiedNestedTypeInCref, parameterListSyntax.Parameters[i].Location);
break;
}
}
}
return(results);
}
/// <summary>
/// At this point, we have a list of viable symbols and no parameter list with which to perform
/// overload resolution. We'll just return the first symbol, giving a diagnostic if there are
/// others.
/// Caveat: If there are multiple candidates and only one is from source, then the source symbol
/// wins and no diagnostic is reported.
/// </summary>
private ImmutableArray <Symbol> ProcessParameterlessCrefMemberLookupResults(
ImmutableArray <Symbol> symbols,
int arity,
MemberCrefSyntax memberSyntax,
TypeArgumentListSyntax?typeArgumentListSyntax,
out Symbol?ambiguityWinner,
BindingDiagnosticBag diagnostics)
{
// If the syntax indicates arity zero, then we match methods of any arity.
// However, if there are both generic and non-generic methods, then the
// generic methods should be ignored.
if (symbols.Length > 1 && arity == 0)
{
bool hasNonGenericMethod = false;
bool hasGenericMethod = false;
foreach (Symbol s in symbols)
{
if (s.Kind != SymbolKind.Method)
{
continue;
}
if (((MethodSymbol)s).Arity == 0)
{
hasNonGenericMethod = true;
}
else
{
hasGenericMethod = true;
}
if (hasGenericMethod && hasNonGenericMethod)
{
break; //Nothing else to be learned.
}
}
if (hasNonGenericMethod && hasGenericMethod)
{
symbols = symbols.WhereAsArray(s =>
s.Kind != SymbolKind.Method || ((MethodSymbol)s).Arity == 0);
}
}
Debug.Assert(!symbols.IsEmpty);
Symbol symbol = symbols[0];
// If there's ambiguity, prefer source symbols.
// Logic is similar to ResultSymbol, but separate because the error handling is totally different.
if (symbols.Length > 1)
{
// Size is known, but IndexOfSymbolFromCurrentCompilation expects a builder.
ArrayBuilder <Symbol> unwrappedSymbols = ArrayBuilder <Symbol> .GetInstance(symbols.Length);
foreach (Symbol wrapped in symbols)
{
unwrappedSymbols.Add(UnwrapAliasNoDiagnostics(wrapped));
}
BestSymbolInfo secondBest;
BestSymbolInfo best = GetBestSymbolInfo(unwrappedSymbols, out secondBest);
Debug.Assert(!best.IsNone);
Debug.Assert(!secondBest.IsNone);
unwrappedSymbols.Free();
int symbolIndex = 0;
if (best.IsFromCompilation)
{
symbolIndex = best.Index;
symbol = symbols[symbolIndex]; // NOTE: symbols, not unwrappedSymbols.
}
if (symbol.Kind == SymbolKind.TypeParameter)
{
CrefSyntax crefSyntax = GetRootCrefSyntax(memberSyntax);
diagnostics.Add(ErrorCode.WRN_BadXMLRefTypeVar, crefSyntax.Location, crefSyntax.ToString());
}
else if (secondBest.IsFromCompilation == best.IsFromCompilation)
{
CrefSyntax crefSyntax = GetRootCrefSyntax(memberSyntax);
int otherIndex = symbolIndex == 0 ? 1 : 0;
diagnostics.Add(ErrorCode.WRN_AmbiguousXMLReference, crefSyntax.Location, crefSyntax.ToString(), symbol, symbols[otherIndex]);
ambiguityWinner = ConstructWithCrefTypeParameters(arity, typeArgumentListSyntax, symbol);
return(symbols.SelectAsArray(sym => ConstructWithCrefTypeParameters(arity, typeArgumentListSyntax, sym)));
}
}
else if (symbol.Kind == SymbolKind.TypeParameter)
{
CrefSyntax crefSyntax = GetRootCrefSyntax(memberSyntax);
diagnostics.Add(ErrorCode.WRN_BadXMLRefTypeVar, crefSyntax.Location, crefSyntax.ToString());
}
ambiguityWinner = null;
return(ImmutableArray.Create <Symbol>(ConstructWithCrefTypeParameters(arity, typeArgumentListSyntax, symbol)));
}
internal static BoundBlock ConstructFieldLikeEventAccessorBody_Regular(SourceEventSymbol eventSymbol, bool isAddMethod, CSharpCompilation compilation, BindingDiagnosticBag diagnostics)
{
CSharpSyntaxNode syntax = eventSymbol.CSharpSyntaxNode;
TypeSymbol delegateType = eventSymbol.Type;
MethodSymbol accessor = isAddMethod ? eventSymbol.AddMethod : eventSymbol.RemoveMethod;
ParameterSymbol thisParameter = accessor.ThisParameter;
TypeSymbol boolType = compilation.GetSpecialType(SpecialType.System_Boolean);
SpecialMember updateMethodId = isAddMethod ? SpecialMember.System_Delegate__Combine : SpecialMember.System_Delegate__Remove;
MethodSymbol updateMethod = (MethodSymbol)compilation.GetSpecialTypeMember(updateMethodId);
BoundStatement @return = new BoundReturnStatement(syntax,
refKind: RefKind.None,
expressionOpt: null,
@checked: false)
{
WasCompilerGenerated = true
};
if (updateMethod == null)
{
MemberDescriptor memberDescriptor = SpecialMembers.GetDescriptor(updateMethodId);
diagnostics.Add(new CSDiagnostic(new CSDiagnosticInfo(ErrorCode.ERR_MissingPredefinedMember,
memberDescriptor.DeclaringTypeMetadataName,
memberDescriptor.Name),
syntax.Location));
return(BoundBlock.SynthesizedNoLocals(syntax, @return));
}
Binder.ReportUseSite(updateMethod, diagnostics, syntax);
BoundThisReference fieldReceiver = eventSymbol.IsStatic ?
null :
new BoundThisReference(syntax, thisParameter.Type)
{
WasCompilerGenerated = true
};
BoundFieldAccess boundBackingField = new BoundFieldAccess(syntax,
receiver: fieldReceiver,
fieldSymbol: eventSymbol.AssociatedField,
constantValueOpt: null)
{
WasCompilerGenerated = true
};
BoundParameter boundParameter = new BoundParameter(syntax,
parameterSymbol: accessor.Parameters[0])
{
WasCompilerGenerated = true
};
BoundExpression delegateUpdate;
MethodSymbol compareExchangeMethod = (MethodSymbol)compilation.GetWellKnownTypeMember(WellKnownMember.System_Threading_Interlocked__CompareExchange_T);
if ((object)compareExchangeMethod == null)
{
// (DelegateType)Delegate.Combine(_event, value)
delegateUpdate = BoundConversion.SynthesizedNonUserDefined(syntax,
operand: BoundCall.Synthesized(syntax,
receiverOpt: null,
method: updateMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundBackingField, boundParameter)),
conversion: Conversion.ExplicitReference,
type: delegateType);
// _event = (DelegateType)Delegate.Combine(_event, value);
BoundStatement eventUpdate = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundBackingField,
right: delegateUpdate,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
return(BoundBlock.SynthesizedNoLocals(syntax,
statements: ImmutableArray.Create <BoundStatement>(
eventUpdate,
@return)));
}
compareExchangeMethod = compareExchangeMethod.Construct(ImmutableArray.Create <TypeSymbol>(delegateType));
Binder.ReportUseSite(compareExchangeMethod, diagnostics, syntax);
GeneratedLabelSymbol loopLabel = new GeneratedLabelSymbol("loop");
const int numTemps = 3;
LocalSymbol[] tmps = new LocalSymbol[numTemps];
BoundLocal[] boundTmps = new BoundLocal[numTemps];
for (int i = 0; i < numTemps; i++)
{
tmps[i] = new SynthesizedLocal(accessor, TypeWithAnnotations.Create(delegateType), SynthesizedLocalKind.LoweringTemp);
boundTmps[i] = new BoundLocal(syntax, tmps[i], null, delegateType)
{
WasCompilerGenerated = true
};
}
// tmp0 = _event;
BoundStatement tmp0Init = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[0],
right: boundBackingField,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// LOOP:
BoundStatement loopStart = new BoundLabelStatement(syntax,
label: loopLabel)
{
WasCompilerGenerated = true
};
// tmp1 = tmp0;
BoundStatement tmp1Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[1],
right: boundTmps[0],
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// (DelegateType)Delegate.Combine(tmp1, value)
delegateUpdate = BoundConversion.SynthesizedNonUserDefined(syntax,
operand: BoundCall.Synthesized(syntax,
receiverOpt: null,
method: updateMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundTmps[1], boundParameter)),
conversion: Conversion.ExplicitReference,
type: delegateType);
// tmp2 = (DelegateType)Delegate.Combine(tmp1, value);
BoundStatement tmp2Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[2],
right: delegateUpdate,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// Interlocked.CompareExchange<DelegateType>(ref _event, tmp2, tmp1)
BoundExpression compareExchange = BoundCall.Synthesized(syntax,
receiverOpt: null,
method: compareExchangeMethod,
arguments: ImmutableArray.Create <BoundExpression>(boundBackingField, boundTmps[2], boundTmps[1]));
// tmp0 = Interlocked.CompareExchange<DelegateType>(ref _event, tmp2, tmp1);
BoundStatement tmp0Update = new BoundExpressionStatement(syntax,
expression: new BoundAssignmentOperator(syntax,
left: boundTmps[0],
right: compareExchange,
type: delegateType)
{
WasCompilerGenerated = true
})
{
WasCompilerGenerated = true
};
// tmp0 == tmp1 // i.e. exit when they are equal, jump to start otherwise
BoundExpression loopExitCondition = new BoundBinaryOperator(syntax,
operatorKind: BinaryOperatorKind.ObjectEqual,
left: boundTmps[0],
right: boundTmps[1],
constantValueOpt: null,
methodOpt: null,
constrainedToTypeOpt: null,
resultKind: LookupResultKind.Viable,
type: boolType)
{
WasCompilerGenerated = true
};
// branchfalse (tmp0 == tmp1) LOOP
BoundStatement loopEnd = new BoundConditionalGoto(syntax,
condition: loopExitCondition,
jumpIfTrue: false,
label: loopLabel)
{
WasCompilerGenerated = true
};
return(new BoundBlock(syntax,
locals: tmps.AsImmutable(),
statements: ImmutableArray.Create <BoundStatement>(
tmp0Init,
loopStart,
tmp1Update,
tmp2Update,
tmp0Update,
loopEnd,
@return))
{
WasCompilerGenerated = true
});
}
public static BoundBlock Rewrite(
MethodSymbol method,
BoundBlock block,
TypeCompilationState compilationState,
BindingDiagnosticBag diagnostics,
bool hasTrailingExpression,
bool originalBodyNested)
{
#if DEBUG
// We should only see a trailingExpression if we're in a Script initializer.
Debug.Assert(!hasTrailingExpression || method.IsScriptInitializer);
var initialDiagnosticCount = diagnostics.ToReadOnly().Diagnostics.Length;
#endif
var compilation = method.DeclaringCompilation;
if (method.ReturnsVoid || method.IsIterator || method.IsAsyncEffectivelyReturningTask(compilation))
{
ImmutableArray <FieldSymbol> implicitlyInitializedFields = default;
bool needsImplicitReturn = true;
// we don't analyze synthesized void methods.
if ((method.IsImplicitlyDeclared && !method.IsScriptInitializer) ||
Analyze(compilation, method, block, diagnostics.DiagnosticBag, out needsImplicitReturn, out implicitlyInitializedFields))
{
if (!implicitlyInitializedFields.IsDefault)
{
Debug.Assert(!implicitlyInitializedFields.IsEmpty);
block = PrependImplicitInitializations(block, method, implicitlyInitializedFields, compilationState, diagnostics);
}
if (needsImplicitReturn)
{
block = AppendImplicitReturn(block, method, originalBodyNested);
}
}
}
else if (Analyze(compilation, method, block, diagnostics.DiagnosticBag, out var needsImplicitReturn, out var unusedImplicitlyInitializedFields))
{
Debug.Assert(unusedImplicitlyInitializedFields.IsDefault);
Debug.Assert(needsImplicitReturn);
// If the method is a lambda expression being converted to a non-void delegate type
// and the end point is reachable then suppress the error here; a special error
// will be reported by the lambda binder.
Debug.Assert(method.MethodKind != MethodKind.AnonymousFunction);
// Add implicit "return default(T)" if this is a submission that does not have a trailing expression.
var submissionResultType = (method as SynthesizedInteractiveInitializerMethod)?.ResultType;
if (!hasTrailingExpression && ((object)submissionResultType != null))
{
Debug.Assert(!submissionResultType.IsVoidType());
var trailingExpression = new BoundDefaultExpression(method.GetNonNullSyntaxNode(), submissionResultType);
var newStatements = block.Statements.Add(new BoundReturnStatement(trailingExpression.Syntax, RefKind.None, trailingExpression, @checked: false));
block = new BoundBlock(block.Syntax, ImmutableArray <LocalSymbol> .Empty, newStatements)
{
WasCompilerGenerated = true
};
#if DEBUG
// It should not be necessary to repeat analysis after adding this node, because adding a trailing
// return in cases where one was missing should never produce different Diagnostics.
IEnumerable <Diagnostic> getErrorsOnly(IEnumerable <Diagnostic> diags) => diags.Where(d => d.Severity == DiagnosticSeverity.Error);
var flowAnalysisDiagnostics = DiagnosticBag.GetInstance();
Debug.Assert(!Analyze(compilation, method, block, flowAnalysisDiagnostics, needsImplicitReturn: out _, out unusedImplicitlyInitializedFields));
Debug.Assert(unusedImplicitlyInitializedFields.IsDefault);
// Ignore warnings since flow analysis reports nullability mismatches.
Debug.Assert(getErrorsOnly(flowAnalysisDiagnostics.ToReadOnly()).SequenceEqual(getErrorsOnly(diagnostics.ToReadOnly().Diagnostics.Skip(initialDiagnosticCount))));
flowAnalysisDiagnostics.Free();
#endif
}
// If there's more than one location, then the method is partial and we
// have already reported a non-void partial method error.
else if (method.Locations.Length == 1)
{
diagnostics.Add(ErrorCode.ERR_ReturnExpected, method.Locations[0], method);
}
}
return(block);
}
internal void ValidateParameterNameConflicts(
ImmutableArray <TypeParameterSymbol> typeParameters,
ImmutableArray <ParameterSymbol> parameters,
bool allowShadowingNames,
BindingDiagnosticBag diagnostics)
{
PooledHashSet <string>?tpNames = null;
if (!typeParameters.IsDefaultOrEmpty)
{
tpNames = PooledHashSet <string> .GetInstance();
foreach (var tp in typeParameters)
{
var name = tp.Name;
if (string.IsNullOrEmpty(name))
{
continue;
}
if (!tpNames.Add(name))
{
// Type parameter declaration name conflicts are detected elsewhere
}
else if (!allowShadowingNames)
{
ValidateDeclarationNameConflictsInScope(tp, diagnostics);
}
}
}
PooledHashSet <string>?pNames = null;
if (!parameters.IsDefaultOrEmpty)
{
pNames = PooledHashSet <string> .GetInstance();
foreach (var p in parameters)
{
var name = p.Name;
if (string.IsNullOrEmpty(name))
{
continue;
}
if (tpNames != null && tpNames.Contains(name))
{
// CS0412: 'X': a parameter or local variable cannot have the same name as a method type parameter
diagnostics.Add(ErrorCode.ERR_LocalSameNameAsTypeParam, GetLocation(p), name);
}
if (!pNames.Add(name))
{
// The parameter name '{0}' is a duplicate
diagnostics.Add(ErrorCode.ERR_DuplicateParamName, GetLocation(p), name);
}
else if (!allowShadowingNames)
{
ValidateDeclarationNameConflictsInScope(p, diagnostics);
}
}
}
tpNames?.Free();
pNames?.Free();
}
public void AddAnError(BindingDiagnosticBag diagnostics)
{
diagnostics.Add(ErrorCode.ERR_InsufficientStack, GetTooLongOrComplexExpressionErrorLocation(Node));
}
private static void ReportNamesMismatchesIfAny(
BoundExpression left,
BoundExpression right,
ImmutableArray <string> leftNames,
ImmutableArray <string> rightNames,
BindingDiagnosticBag diagnostics
)
{
bool leftIsTupleLiteral = left is BoundTupleExpression;
bool rightIsTupleLiteral = right is BoundTupleExpression;
if (!leftIsTupleLiteral && !rightIsTupleLiteral)
{
return;
}
bool leftNoNames = leftNames.IsDefault;
bool rightNoNames = rightNames.IsDefault;
if (leftNoNames && rightNoNames)
{
return;
}
Debug.Assert(leftNoNames || rightNoNames || leftNames.Length == rightNames.Length);
ImmutableArray <bool> leftInferred = leftIsTupleLiteral
? ((BoundTupleExpression)left).InferredNamesOpt
: default;
bool leftNoInferredNames = leftInferred.IsDefault;
ImmutableArray <bool> rightInferred = rightIsTupleLiteral
? ((BoundTupleExpression)right).InferredNamesOpt
: default;
bool rightNoInferredNames = rightInferred.IsDefault;
int length = leftNoNames ? rightNames.Length : leftNames.Length;
for (int i = 0; i < length; i++)
{
string leftName = leftNoNames ? null : leftNames[i];
string rightName = rightNoNames ? null : rightNames[i];
bool different = string.CompareOrdinal(rightName, leftName) != 0;
if (!different)
{
continue;
}
bool leftWasInferred = leftNoInferredNames ? false : leftInferred[i];
bool rightWasInferred = rightNoInferredNames ? false : rightInferred[i];
bool leftComplaint = leftIsTupleLiteral && leftName != null && !leftWasInferred;
bool rightComplaint = rightIsTupleLiteral && rightName != null && !rightWasInferred;
if (!leftComplaint && !rightComplaint)
{
// No complaints, let's move on
continue;
}
// When in doubt, we'll complain on the right side if it's a literal
bool useRight =
(leftComplaint && rightComplaint) ? rightIsTupleLiteral : rightComplaint;
Location location =
((BoundTupleExpression)(useRight ? right : left)).Arguments[
i
].Syntax.Parent.Location;
string complaintName = useRight ? rightName : leftName;
diagnostics.Add(
ErrorCode.WRN_TupleBinopLiteralNameMismatch,
location,
complaintName
);
}
}
private BoundExpression BindInterpolatedString(InterpolatedStringExpressionSyntax node, BindingDiagnosticBag diagnostics)
{
var builder = ArrayBuilder <BoundExpression> .GetInstance();
var stringType = GetSpecialType(SpecialType.System_String, diagnostics, node);
ConstantValue?resultConstant = null;
bool isResultConstant = true;
if (node.Contents.Count == 0)
{
resultConstant = ConstantValue.Create(string.Empty);
}
else
{
var objectType = GetSpecialType(SpecialType.System_Object, diagnostics, node);
var intType = GetSpecialType(SpecialType.System_Int32, diagnostics, node);
foreach (var content in node.Contents)
{
switch (content.Kind())
{
case SyntaxKind.Interpolation:
{
var interpolation = (InterpolationSyntax)content;
var value = BindValue(interpolation.Expression, diagnostics, BindValueKind.RValue);
if (value.Type is null)
{
value = GenerateConversionForAssignment(objectType, value, diagnostics);
}
else
{
value = BindToNaturalType(value, diagnostics);
_ = GenerateConversionForAssignment(objectType, value, diagnostics);
}
// We need to ensure the argument is not a lambda, method group, etc. It isn't nice to wait until lowering,
// when we perform overload resolution, to report a problem. So we do that check by calling
// GenerateConversionForAssignment with objectType. However we want to preserve the original expression's
// natural type so that overload resolution may select a specialized implementation of string.Format,
// so we discard the result of that call and only preserve its diagnostics.
BoundExpression?alignment = null;
BoundLiteral? format = null;
if (interpolation.AlignmentClause != null)
{
alignment = GenerateConversionForAssignment(intType, BindValue(interpolation.AlignmentClause.Value, diagnostics, Binder.BindValueKind.RValue), diagnostics);
var alignmentConstant = alignment.ConstantValue;
if (alignmentConstant != null && !alignmentConstant.IsBad)
{
const int magnitudeLimit = 32767;
// check that the magnitude of the alignment is "in range".
int alignmentValue = alignmentConstant.Int32Value;
// We do the arithmetic using negative numbers because the largest negative int has no corresponding positive (absolute) value.
alignmentValue = (alignmentValue > 0) ? -alignmentValue : alignmentValue;
if (alignmentValue < -magnitudeLimit)
{
diagnostics.Add(ErrorCode.WRN_AlignmentMagnitude, alignment.Syntax.Location, alignmentConstant.Int32Value, magnitudeLimit);
}
}
else if (!alignment.HasErrors)
{
diagnostics.Add(ErrorCode.ERR_ConstantExpected, interpolation.AlignmentClause.Value.Location);
}
}
if (interpolation.FormatClause != null)
{
var text = interpolation.FormatClause.FormatStringToken.ValueText;
char lastChar;
bool hasErrors = false;
if (text.Length == 0)
{
diagnostics.Add(ErrorCode.ERR_EmptyFormatSpecifier, interpolation.FormatClause.Location);
hasErrors = true;
}
else if (SyntaxFacts.IsWhitespace(lastChar = text[text.Length - 1]) || SyntaxFacts.IsNewLine(lastChar))
{
diagnostics.Add(ErrorCode.ERR_TrailingWhitespaceInFormatSpecifier, interpolation.FormatClause.Location);
hasErrors = true;
}
format = new BoundLiteral(interpolation.FormatClause, ConstantValue.Create(text), stringType, hasErrors);
}
builder.Add(new BoundStringInsert(interpolation, value, alignment, format, null));
if (!isResultConstant ||
value.ConstantValue == null ||
!(interpolation is { FormatClause: null, AlignmentClause: null }) ||
!(value.ConstantValue is { IsString: true, IsBad: false }))
/// <summary>
/// Bind and return a single type parameter constraint clause along with syntax nodes corresponding to type constraints.
/// </summary>
private (TypeParameterConstraintClause, ArrayBuilder <TypeConstraintSyntax>?) BindTypeParameterConstraints(TypeParameterSyntax typeParameterSyntax, TypeParameterConstraintClauseSyntax constraintClauseSyntax, bool isForOverride, BindingDiagnosticBag diagnostics)
{
var constraints = TypeParameterConstraintKind.None;
ArrayBuilder <TypeWithAnnotations>? constraintTypes = null;
ArrayBuilder <TypeConstraintSyntax>?syntaxBuilder = null;
SeparatedSyntaxList <TypeParameterConstraintSyntax> constraintsSyntax = constraintClauseSyntax.Constraints;
Debug.Assert(!InExecutableBinder); // Cannot eagerly report diagnostics handled by LazyMissingNonNullTypesContextDiagnosticInfo
bool hasTypeLikeConstraint = false;
bool reportedOverrideWithConstraints = false;
for (int i = 0, n = constraintsSyntax.Count; i < n; i++)
{
var syntax = constraintsSyntax[i];
switch (syntax.Kind())
{
case SyntaxKind.ClassConstraint:
hasTypeLikeConstraint = true;
if (i != 0)
{
if (!reportedOverrideWithConstraints)
{
reportTypeConstraintsMustBeUniqueAndFirst(syntax, diagnostics);
}
if (isForOverride && (constraints & (TypeParameterConstraintKind.ValueType | TypeParameterConstraintKind.ReferenceType)) != 0)
{
continue;
}
}
var constraintSyntax = (ClassOrStructConstraintSyntax)syntax;
SyntaxToken questionToken = constraintSyntax.QuestionToken;
if (questionToken.IsKind(SyntaxKind.QuestionToken))
{
constraints |= TypeParameterConstraintKind.NullableReferenceType;
if (isForOverride)
{
reportOverrideWithConstraints(ref reportedOverrideWithConstraints, syntax, diagnostics);
}
else if (diagnostics.DiagnosticBag is DiagnosticBag diagnosticBag)
{
LazyMissingNonNullTypesContextDiagnosticInfo.AddAll(this, questionToken, type: null, diagnosticBag);
}
}
else if (isForOverride || AreNullableAnnotationsEnabled(constraintSyntax.ClassOrStructKeyword))
{
constraints |= TypeParameterConstraintKind.NotNullableReferenceType;
}
else
{
constraints |= TypeParameterConstraintKind.ReferenceType;
}
continue;
case SyntaxKind.StructConstraint:
hasTypeLikeConstraint = true;
if (i != 0)
{
if (!reportedOverrideWithConstraints)
{
reportTypeConstraintsMustBeUniqueAndFirst(syntax, diagnostics);
}
if (isForOverride && (constraints & (TypeParameterConstraintKind.ValueType | TypeParameterConstraintKind.ReferenceType)) != 0)
{
continue;
}
}
constraints |= TypeParameterConstraintKind.ValueType;
continue;
case SyntaxKind.ConstructorConstraint:
if (isForOverride)
{
reportOverrideWithConstraints(ref reportedOverrideWithConstraints, syntax, diagnostics);
continue;
}
if ((constraints & TypeParameterConstraintKind.ValueType) != 0)
{
diagnostics.Add(ErrorCode.ERR_NewBoundWithVal, syntax.GetFirstToken().GetLocation());
}
if ((constraints & TypeParameterConstraintKind.Unmanaged) != 0)
{
diagnostics.Add(ErrorCode.ERR_NewBoundWithUnmanaged, syntax.GetFirstToken().GetLocation());
}
if (i != n - 1)
{
diagnostics.Add(ErrorCode.ERR_NewBoundMustBeLast, syntax.GetFirstToken().GetLocation());
}
constraints |= TypeParameterConstraintKind.Constructor;
continue;
case SyntaxKind.DefaultConstraint:
if (!isForOverride)
{
diagnostics.Add(ErrorCode.ERR_DefaultConstraintOverrideOnly, syntax.GetLocation());
}
if (i != 0)
{
if (!reportedOverrideWithConstraints)
{
reportTypeConstraintsMustBeUniqueAndFirst(syntax, diagnostics);
}
if (isForOverride && (constraints & (TypeParameterConstraintKind.ValueType | TypeParameterConstraintKind.ReferenceType)) != 0)
{
continue;
}
}
constraints |= TypeParameterConstraintKind.Default;
continue;
case SyntaxKind.TypeConstraint:
if (isForOverride)
{
reportOverrideWithConstraints(ref reportedOverrideWithConstraints, syntax, diagnostics);
}
else
{
hasTypeLikeConstraint = true;
if (constraintTypes == null)
{
constraintTypes = ArrayBuilder <TypeWithAnnotations> .GetInstance();
syntaxBuilder = ArrayBuilder <TypeConstraintSyntax> .GetInstance();
}
var typeConstraintSyntax = (TypeConstraintSyntax)syntax;
var typeSyntax = typeConstraintSyntax.Type;
var type = BindTypeOrConstraintKeyword(typeSyntax, diagnostics, out ConstraintContextualKeyword keyword);
switch (keyword)
{
case ConstraintContextualKeyword.Unmanaged:
if (i != 0)
{
reportTypeConstraintsMustBeUniqueAndFirst(typeSyntax, diagnostics);
continue;
}
// This should produce diagnostics if the types are missing
GetWellKnownType(WellKnownType.System_Runtime_InteropServices_UnmanagedType, diagnostics, typeSyntax);
GetSpecialType(SpecialType.System_ValueType, diagnostics, typeSyntax);
constraints |= TypeParameterConstraintKind.Unmanaged;
continue;
case ConstraintContextualKeyword.NotNull:
if (i != 0)
{
reportTypeConstraintsMustBeUniqueAndFirst(typeSyntax, diagnostics);
}
constraints |= TypeParameterConstraintKind.NotNull;
continue;
case ConstraintContextualKeyword.None:
break;
default:
throw ExceptionUtilities.UnexpectedValue(keyword);
}
constraintTypes.Add(type);
syntaxBuilder !.Add(typeConstraintSyntax);
}
continue;
default:
throw ExceptionUtilities.UnexpectedValue(syntax.Kind());
}
}
if (!isForOverride && !hasTypeLikeConstraint && !AreNullableAnnotationsEnabled(typeParameterSyntax.Identifier))
{
constraints |= TypeParameterConstraintKind.ObliviousNullabilityIfReferenceType;
}
Debug.Assert(!isForOverride ||
(constraints & (TypeParameterConstraintKind.ReferenceType | TypeParameterConstraintKind.ValueType)) != (TypeParameterConstraintKind.ReferenceType | TypeParameterConstraintKind.ValueType));
return(TypeParameterConstraintClause.Create(constraints, constraintTypes?.ToImmutableAndFree() ?? ImmutableArray <TypeWithAnnotations> .Empty), syntaxBuilder);
private bool ValidateAttributeUsage(
CSharpAttributeData attribute,
AttributeSyntax node,
CSharpCompilation compilation,
AttributeLocation symbolPart,
BindingDiagnosticBag diagnostics,
HashSet <NamedTypeSymbol> uniqueAttributeTypes
)
{
Debug.Assert(!attribute.HasErrors);
NamedTypeSymbol attributeType = attribute.AttributeClass;
AttributeUsageInfo attributeUsageInfo = attributeType.GetAttributeUsageInfo();
// Given attribute can't be specified more than once if AllowMultiple is false.
if (!uniqueAttributeTypes.Add(attributeType) && !attributeUsageInfo.AllowMultiple)
{
diagnostics.Add(
ErrorCode.ERR_DuplicateAttribute,
node.Name.Location,
node.GetErrorDisplayName()
);
return(false);
}
// Verify if the attribute type can be applied to given owner symbol.
AttributeTargets attributeTarget;
if (symbolPart == AttributeLocation.Return)
{
// attribute on return type
Debug.Assert(this.Kind == SymbolKind.Method);
attributeTarget = AttributeTargets.ReturnValue;
}
else
{
attributeTarget = this.GetAttributeTarget();
}
if ((attributeTarget & attributeUsageInfo.ValidTargets) == 0)
{
// generate error
diagnostics.Add(
ErrorCode.ERR_AttributeOnBadSymbolType,
node.Name.Location,
node.GetErrorDisplayName(),
attributeUsageInfo.GetValidTargetsErrorArgument()
);
return(false);
}
if (attribute.IsSecurityAttribute(compilation))
{
switch (this.Kind)
{
case SymbolKind.Assembly:
case SymbolKind.NamedType:
case SymbolKind.Method:
break;
default:
// CS7070: Security attribute '{0}' is not valid on this declaration type. Security attributes are only valid on assembly, type and method declarations.
diagnostics.Add(
ErrorCode.ERR_SecurityAttributeInvalidTarget,
node.Name.Location,
node.GetErrorDisplayName()
);
return(false);
}
}
return(true);
}
private static bool MatchAttributeTarget(
IAttributeTargetSymbol attributeTarget,
AttributeLocation symbolPart,
AttributeTargetSpecifierSyntax targetOpt,
BindingDiagnosticBag diagnostics
)
{
IAttributeTargetSymbol attributesOwner = attributeTarget.AttributesOwner;
// Determine if the target symbol owns the attribute declaration.
// We need to report diagnostics only once, so do it when visiting attributes for the owner.
bool isOwner =
symbolPart == AttributeLocation.None &&
ReferenceEquals(attributesOwner, attributeTarget);
if (targetOpt == null)
{
// only attributes with an explicit target match if the symbol doesn't own the attributes:
return(isOwner);
}
AttributeLocation allowedTargets = attributesOwner.AllowedAttributeLocations;
AttributeLocation explicitTarget = targetOpt.GetAttributeLocation();
if (explicitTarget == AttributeLocation.None)
{
// error: unknown attribute location
if (isOwner)
{
//NOTE: ValueText so that we accept targets like "@return", to match dev10 (DevDiv #2591).
diagnostics.Add(
ErrorCode.WRN_InvalidAttributeLocation,
targetOpt.Identifier.GetLocation(),
targetOpt.Identifier.ValueText,
allowedTargets.ToDisplayString()
);
}
return(false);
}
if ((explicitTarget & allowedTargets) == 0)
{
// error: invalid target for symbol
if (isOwner)
{
if (allowedTargets == AttributeLocation.None)
{
switch (attributeTarget.DefaultAttributeLocation)
{
case AttributeLocation.Assembly:
case AttributeLocation.Module:
// global attributes are disallowed in interactive code:
diagnostics.Add(
ErrorCode.ERR_GlobalAttributesNotAllowed,
targetOpt.Identifier.GetLocation()
);
break;
default:
// currently this can't happen
throw ExceptionUtilities.UnexpectedValue(
attributeTarget.DefaultAttributeLocation
);
}
}
else
{
diagnostics.Add(
ErrorCode.WRN_AttributeLocationOnBadDeclaration,
targetOpt.Identifier.GetLocation(),
targetOpt.Identifier.ToString(),
allowedTargets.ToDisplayString()
);
}
}
return(false);
}
if (symbolPart == AttributeLocation.None)
{
return(explicitTarget == attributeTarget.DefaultAttributeLocation);
}
else
{
return(explicitTarget == symbolPart);
}
}
internal static BoundStatement Rewrite(
BoundStatement bodyWithAwaitLifted,
MethodSymbol method,
int methodOrdinal,
VariableSlotAllocator slotAllocatorOpt,
TypeCompilationState compilationState,
BindingDiagnosticBag diagnostics,
out AsyncStateMachine stateMachineType
)
{
if (!method.IsAsync)
{
stateMachineType = null;
return(bodyWithAwaitLifted);
}
CSharpCompilation compilation = method.DeclaringCompilation;
bool isAsyncEnumerableOrEnumerator =
method.IsAsyncReturningIAsyncEnumerable(compilation) ||
method.IsAsyncReturningIAsyncEnumerator(compilation);
if (isAsyncEnumerableOrEnumerator && !method.IsIterator)
{
bool containsAwait = AwaitDetector.ContainsAwait(bodyWithAwaitLifted);
diagnostics.Add(
containsAwait
? ErrorCode.ERR_PossibleAsyncIteratorWithoutYield
: ErrorCode.ERR_PossibleAsyncIteratorWithoutYieldOrAwait,
method.Locations[0],
method.ReturnTypeWithAnnotations
);
stateMachineType = null;
return(bodyWithAwaitLifted);
}
// The CLR doesn't support adding fields to structs, so in order to enable EnC in an async method we need to generate a class.
// For async-iterators, we also need to generate a class.
var typeKind =
(compilationState.Compilation.Options.EnableEditAndContinue || method.IsIterator)
? TypeKind.Class
: TypeKind.Struct;
stateMachineType = new AsyncStateMachine(
slotAllocatorOpt,
compilationState,
method,
methodOrdinal,
typeKind
);
compilationState.ModuleBuilderOpt.CompilationState.SetStateMachineType(
method,
stateMachineType
);
AsyncRewriter rewriter = isAsyncEnumerableOrEnumerator
? new AsyncIteratorRewriter(
bodyWithAwaitLifted,
method,
methodOrdinal,
stateMachineType,
slotAllocatorOpt,
compilationState,
diagnostics
)
: new AsyncRewriter(
bodyWithAwaitLifted,
method,
methodOrdinal,
stateMachineType,
slotAllocatorOpt,
compilationState,
diagnostics
);
if (!rewriter.VerifyPresenceOfRequiredAPIs())
{
return(bodyWithAwaitLifted);
}
try
{
return(rewriter.Rewrite());
}
catch (SyntheticBoundNodeFactory.MissingPredefinedMember ex)
{
diagnostics.Add(ex.Diagnostic);
return(new BoundBadStatement(
bodyWithAwaitLifted.Syntax,
ImmutableArray.Create <BoundNode>(bodyWithAwaitLifted),
hasErrors: true
));
}
}
internal BoundExpression BindQuery(QueryExpressionSyntax node, BindingDiagnosticBag diagnostics)
{
var fromClause = node.FromClause;
var boundFromExpression = BindLeftOfPotentialColorColorMemberAccess(fromClause.Expression, diagnostics);
// If the from expression is of the type dynamic we can't infer the types for any lambdas that occur in the query.
// Only if there are none we could bind the query but we report an error regardless since such queries are not useful.
if (boundFromExpression.HasDynamicType())
{
diagnostics.Add(ErrorCode.ERR_BadDynamicQuery, fromClause.Expression.Location);
boundFromExpression = BadExpression(fromClause.Expression, boundFromExpression);
}
else
{
boundFromExpression = BindToNaturalType(boundFromExpression, diagnostics);
}
QueryTranslationState state = new QueryTranslationState();
state.fromExpression = MakeMemberAccessValue(boundFromExpression, diagnostics);
var x = state.rangeVariable = state.AddRangeVariable(this, fromClause.Identifier, diagnostics);
for (int i = node.Body.Clauses.Count - 1; i >= 0; i--)
{
state.clauses.Push(node.Body.Clauses[i]);
}
state.selectOrGroup = node.Body.SelectOrGroup;
// A from clause that explicitly specifies a range variable type
// from T x in e
// is translated into
// from x in ( e ) . Cast < T > ( )
BoundExpression?cast = null;
if (fromClause.Type != null)
{
var typeRestriction = BindTypeArgument(fromClause.Type, diagnostics);
cast = MakeQueryInvocation(fromClause, state.fromExpression, "Cast", fromClause.Type, typeRestriction, diagnostics);
state.fromExpression = cast;
}
state.fromExpression = MakeQueryClause(fromClause, state.fromExpression, x, castInvocation: cast);
BoundExpression result = BindQueryInternal1(state, diagnostics);
for (QueryContinuationSyntax?continuation = node.Body.Continuation; continuation != null; continuation = continuation.Body.Continuation)
{
// A query expression with a continuation
// from ... into x ...
// is translated into
// from x in ( from ... ) ...
state.Clear();
state.fromExpression = result;
x = state.rangeVariable = state.AddRangeVariable(this, continuation.Identifier, diagnostics);
Debug.Assert(state.clauses.IsEmpty());
var clauses = continuation.Body.Clauses;
for (int i = clauses.Count - 1; i >= 0; i--)
{
state.clauses.Push(clauses[i]);
}
state.selectOrGroup = continuation.Body.SelectOrGroup;
result = BindQueryInternal1(state, diagnostics);
result = MakeQueryClause(continuation.Body, result, x);
result = MakeQueryClause(continuation, result, x);
}
state.Free();
return(MakeQueryClause(node, result));
}
private XNode[] RewriteIncludeElement(XElement includeElement, string currentXmlFilePath, CSharpSyntaxNode originatingSyntax, out string commentMessage)
{
Location location = GetIncludeElementLocation(includeElement, ref currentXmlFilePath, ref originatingSyntax);
Debug.Assert(originatingSyntax != null);
bool diagnose = originatingSyntax.SyntaxTree.ReportDocumentationCommentDiagnostics();
if (!EnterIncludeElement(location))
{
// NOTE: these must exist since we're already processed this node elsewhere in the call stack.
XAttribute fileAttr = includeElement.Attribute(XName.Get(DocumentationCommentXmlNames.FileAttributeName));
XAttribute pathAttr = includeElement.Attribute(XName.Get(DocumentationCommentXmlNames.PathAttributeName));
string filePathValue = fileAttr.Value;
string xpathValue = pathAttr.Value;
if (diagnose)
{
_diagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, new LocalizableErrorArgument(MessageID.IDS_OperationCausedStackOverflow));
}
commentMessage = ErrorFacts.GetMessage(MessageID.IDS_XMLNOINCLUDE, CultureInfo.CurrentUICulture);
// Don't inspect the children - we're already in a cycle.
return(new XNode[] { new XComment(commentMessage), includeElement.Copy(copyAttributeAnnotations: false) });
}
DiagnosticBag includeDiagnostics = DiagnosticBag.GetInstance();
try
{
XAttribute fileAttr = includeElement.Attribute(XName.Get(DocumentationCommentXmlNames.FileAttributeName));
XAttribute pathAttr = includeElement.Attribute(XName.Get(DocumentationCommentXmlNames.PathAttributeName));
bool hasFileAttribute = fileAttr != null;
bool hasPathAttribute = pathAttr != null;
if (!hasFileAttribute || !hasPathAttribute)
{
var subMessage = hasFileAttribute ? MessageID.IDS_XMLMISSINGINCLUDEPATH.Localize() : MessageID.IDS_XMLMISSINGINCLUDEFILE.Localize();
includeDiagnostics.Add(ErrorCode.WRN_InvalidInclude, location, subMessage);
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLBADINCLUDE);
return(null);
}
string xpathValue = pathAttr.Value;
string filePathValue = fileAttr.Value;
var resolver = _compilation.Options.XmlReferenceResolver;
if (resolver == null)
{
includeDiagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, new CodeAnalysisResourcesLocalizableErrorArgument(nameof(CodeAnalysisResources.XmlReferencesNotSupported)));
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE);
return(null);
}
string resolvedFilePath = resolver.ResolveReference(filePathValue, currentXmlFilePath);
if (resolvedFilePath == null)
{
// NOTE: same behavior as IOException.
includeDiagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, new CodeAnalysisResourcesLocalizableErrorArgument(nameof(CodeAnalysisResources.FileNotFound)));
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE);
return(null);
}
if (_includedFileCache == null)
{
_includedFileCache = new DocumentationCommentIncludeCache(resolver);
}
try
{
XDocument doc;
try
{
doc = _includedFileCache.GetOrMakeDocument(resolvedFilePath);
}
catch (IOException e)
{
// NOTE: same behavior as resolvedFilePath == null.
includeDiagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, e.Message);
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE);
return(null);
}
Debug.Assert(doc != null);
string errorMessage;
bool invalidXPath;
XElement[] loadedElements = XmlUtilities.TrySelectElements(doc, xpathValue, out errorMessage, out invalidXPath);
if (loadedElements == null)
{
includeDiagnostics.Add(ErrorCode.WRN_FailedInclude, location, filePathValue, xpathValue, errorMessage);
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLFAILEDINCLUDE);
if (invalidXPath)
{
// leave the include node as is
return(null);
}
if (location.IsInSource)
{
// As in Dev11, return only the comment - drop the include element.
return(new XNode[] { new XComment(commentMessage) });
}
else
{
commentMessage = null;
return(Array.Empty <XNode>());
}
}
if (loadedElements != null && loadedElements.Length > 0)
{
// change the current XML file path for nodes contained in the document:
XNode[] result = RewriteMany(loadedElements, resolvedFilePath, originatingSyntax);
// The elements could be rewritten away if they are includes that refer to invalid
// (but existing and accessible) XML files. If this occurs, behave as if we
// had failed to find any XPath results (as in Dev11).
if (result.Length > 0)
{
// NOTE: in this case, we do NOT visit the children of the include element -
// they are dropped.
commentMessage = null;
return(result);
}
}
commentMessage = MakeCommentMessage(location, MessageID.IDS_XMLNOINCLUDE);
return(null);
}
catch (XmlException e)
{
// NOTE: invalid XML is handled differently from other errors - we don't include the include element
// in the results and the location is in the included (vs includING) file.
Location errorLocation = XmlLocation.Create(e, resolvedFilePath);
includeDiagnostics.Add(ErrorCode.WRN_XMLParseIncludeError, errorLocation, GetDescription(e)); //NOTE: location is in included file.
if (location.IsInSource)
{
commentMessage = string.Format(ErrorFacts.GetMessage(MessageID.IDS_XMLIGNORED2, CultureInfo.CurrentUICulture), resolvedFilePath);
// As in Dev11, return only the comment - drop the include element.
return(new XNode[] { new XComment(commentMessage) });
}
else
{
commentMessage = null;
return(Array.Empty <XNode>());
}
}
}
finally
{
if (diagnose)
{
_diagnostics.AddRange(includeDiagnostics);
}
includeDiagnostics.Free();
LeaveIncludeElement(location);
}
}
static void reportTypeConstraintsMustBeUniqueAndFirst(CSharpSyntaxNode syntax, BindingDiagnosticBag diagnostics)
{
diagnostics.Add(ErrorCode.ERR_TypeConstraintsMustBeUniqueAndFirst, syntax.GetLocation());
}
/// <summary>
/// Return a collection of bound constraint clauses indexed by type parameter
/// ordinal. All constraint clauses are bound, even if there are multiple constraints
/// for the same type parameter, or constraints for unrecognized type parameters.
/// Extra constraints are not included in the returned collection however.
/// </summary>
internal ImmutableArray <TypeParameterConstraintClause> BindTypeParameterConstraintClauses(
Symbol containingSymbol,
ImmutableArray <TypeParameterSymbol> typeParameters,
TypeParameterListSyntax typeParameterList,
SyntaxList <TypeParameterConstraintClauseSyntax> clauses,
BindingDiagnosticBag diagnostics,
bool performOnlyCycleSafeValidation,
bool isForOverride = false)
{
Debug.Assert(this.Flags.Includes(BinderFlags.GenericConstraintsClause));
RoslynDebug.Assert((object)containingSymbol != null);
Debug.Assert((containingSymbol.Kind == SymbolKind.NamedType) || (containingSymbol.Kind == SymbolKind.Method));
Debug.Assert(typeParameters.Length > 0);
Debug.Assert(clauses.Count > 0);
int n = typeParameters.Length;
// Create a map from type parameter name to ordinal.
// No need to report duplicate names since duplicates
// are reported when the type parameters are bound.
var names = new Dictionary <string, int>(n, StringOrdinalComparer.Instance);
foreach (var typeParameter in typeParameters)
{
var name = typeParameter.Name;
if (!names.ContainsKey(name))
{
names.Add(name, names.Count);
}
}
// An array of constraint clauses, one for each type parameter, indexed by ordinal.
var results = ArrayBuilder <TypeParameterConstraintClause?> .GetInstance(n, fillWithValue : null);
var syntaxNodes = ArrayBuilder <ArrayBuilder <TypeConstraintSyntax>?> .GetInstance(n, fillWithValue : null);
// Bind each clause and add to the results.
foreach (var clause in clauses)
{
var name = clause.Name.Identifier.ValueText;
RoslynDebug.Assert(name is object);
int ordinal;
if (names.TryGetValue(name, out ordinal))
{
Debug.Assert(ordinal >= 0);
Debug.Assert(ordinal < n);
(TypeParameterConstraintClause constraintClause, ArrayBuilder <TypeConstraintSyntax>?typeConstraintNodes) = this.BindTypeParameterConstraints(typeParameterList.Parameters[ordinal], clause, isForOverride, diagnostics);
if (results[ordinal] == null)
{
results[ordinal] = constraintClause;
syntaxNodes[ordinal] = typeConstraintNodes;
}
else
{
// "A constraint clause has already been specified for type parameter '{0}'. ..."
diagnostics.Add(ErrorCode.ERR_DuplicateConstraintClause, clause.Name.Location, name);
typeConstraintNodes?.Free();
}
}
else
{
// Unrecognized type parameter. Don't bother binding the constraints
// (the ": I<U>" in "where U : I<U>") since that will lead to additional
// errors ("type or namespace 'U' could not be found") if the type
// parameter is referenced in the constraints.
// "'{1}' does not define type parameter '{0}'"
diagnostics.Add(ErrorCode.ERR_TyVarNotFoundInConstraint, clause.Name.Location, name, containingSymbol.ConstructedFrom());
}
}
// Add default values for type parameters without constraint clauses.
for (int i = 0; i < n; i++)
{
if (results[i] == null)
{
results[i] = GetDefaultTypeParameterConstraintClause(typeParameterList.Parameters[i], isForOverride);
}
}
RemoveInvalidConstraints(typeParameters, results !, syntaxNodes, performOnlyCycleSafeValidation, diagnostics);
foreach (var typeConstraintsSyntaxes in syntaxNodes)
{
typeConstraintsSyntaxes?.Free();
}
syntaxNodes.Free();
return(results.ToImmutableAndFree() !);
}
private void Error(ErrorCode code, BoundNode node, params object[] args)
{
_diagnostics.Add(code, node.Syntax.Location, args);
}
