/// <summary>
/// Handles the case of:
/// function myFunction(args: "A" | "B" | "C");
/// const myVar = myFunc({completion happens here});
/// </summary>
/// <remarks>
/// The type is based on the expected type of the initializer. So we ask the type checker for
/// that type. We then expand all union types and then return the unique set
/// of possibilities.
/// </remarks>
internal static IEnumerable <CompletionItem> CreateCompletionFromCallExperssion(CompletionState completionState, INode completionNode)
{
var callExpression = completionNode.Cast <ICallExpression>();
// The user can type a random function that looks like a call expresion:
// const myVar == fooBar();
// In which case we have nothing to resolve
var callSymbol = completionState.TypeChecker.GetSymbolAtLocation(callExpression.Expression);
if (callSymbol == null)
{
return(null);
}
var typeOfExpression = completionState.TypeChecker.GetTypeAtLocation(callExpression.Expression);
if (typeOfExpression == null)
{
return(null);
}
var signature = completionState.TypeChecker.GetSignaturesOfType(typeOfExpression, SignatureKind.Call).FirstOrDefault();
var parameterIndex = DScriptFunctionSignature.GetActiveParameterIndex(callExpression, completionState.StartingNode);
var parameterCount = signature?.Parameters?.Count ?? 0;
if (parameterIndex >= 0 && parameterIndex < parameterCount)
{
var parameter = signature.Parameters[parameterIndex];
var type = completionState.TypeChecker.GetTypeAtLocation(parameter.GetFirstDeclarationOrDefault());
if (type != null)
{
var results = AddStringLiteralSymbolsFromType(type, completionState.TypeChecker);
return(CreateCompletionItemsFromStrings(results));
}
}
return(null);
}
/// <nodoc/>
public Result <SignatureHelp, ResponseError> SignatureHelp(TextDocumentPositionParams positionParams, CancellationToken token)
{
// TODO: support cancellation
if (!TryFindNode(positionParams, out var nodeAtPosition))
{
return(Result <SignatureHelp, ResponseError> .Success(new SignatureHelp()));
}
ICallExpression callExpression = GetContainingCallExpression(nodeAtPosition);
if (callExpression == null)
{
Logger.LanguageServerNonCriticalInternalIssue(LoggingContext, FormattableStringEx.I($"Couldn't find call expression containing {nodeAtPosition.GetFormattedText()}"));
return(Result <SignatureHelp, ResponseError> .Success(new SignatureHelp()));
}
var callSymbol = TypeChecker.GetSymbolAtLocation(callExpression.Expression);
// If the user has typed a call expresion to a symbol (function) that doesn't exist (i.e. "foo.bar()")
// Then just issue a debug writeline and a success instead of crashing.
// There is going to be a red-line squiggle under it anyway.
if (callSymbol == null)
{
Logger.LanguageServerNonCriticalInternalIssue(LoggingContext, FormattableStringEx.I($"Couldn't find symbol for call expression containing {nodeAtPosition.GetFormattedText()}"));
return(Result <SignatureHelp, ResponseError> .Success(new SignatureHelp()));
}
var signature = TypeChecker.GetSignaturesOfType(TypeChecker.GetTypeAtLocation(callExpression.Expression), SignatureKind.Call).FirstOrDefault();
if (signature == null)
{
Logger.LanguageServerNonCriticalInternalIssue(LoggingContext, FormattableStringEx.I($"Couldn't find call signature for call expression containing {nodeAtPosition.GetFormattedText()}"));
return(Result <SignatureHelp, ResponseError> .Success(new SignatureHelp()));
}
var functionDeclaration = DScriptFunctionSignature.FromSignature(callSymbol.Name, signature);
var parameterInformations = functionDeclaration.FormattedParameterNames.Select(formattedParameterName => new ParameterInformation()
{
Label = formattedParameterName,
});
int activeParameterIndex = DScriptFunctionSignature.GetActiveParameterIndex(callExpression, nodeAtPosition);
var signatureHelp = new SignatureHelp()
{
Signatures = new SignatureInformation[]
{
new SignatureInformation()
{
Label = functionDeclaration.FormattedFullFunctionSignature,
Parameters = parameterInformations.ToArray(),
Documentation = DocumentationUtilities.GetDocumentationForSymbolAsString(callSymbol),
},
},
ActiveParameter = activeParameterIndex,
ActiveSignature = 0,
};
return(Result <SignatureHelp, ResponseError> .Success(signatureHelp));
}