static void AddItems(ImmutableArray <CompletionItem> items, CompletionContext completionContext, HashSet <string> namespacesInScope, TelemetryCounter counter)
{
foreach (var item in items)
{
var containingNamespace = ImportCompletionItem.GetContainingNamespace(item);
if (!namespacesInScope.Contains(containingNamespace))
{
// We can return cached item directly, item's span will be fixed by completion service.
// On the other hand, because of this (i.e. mutating the span of cached item for each run),
// the provider can not be used as a service by components that might be run in parallel
// with completion, which would be a race.
completionContext.AddItem(item);
counter.ItemsCount++;;
}
}
}
public override async Task <CompletionChange> GetChangeAsync(
Document document, CompletionItem completionItem, char?commitKey, CancellationToken cancellationToken)
{
var containingNamespace = ImportCompletionItem.GetContainingNamespace(completionItem);
var provideParenthesisCompletion = await ShouldProvideParenthesisCompletionAsync(
document,
completionItem,
commitKey,
cancellationToken).ConfigureAwait(false);
var insertText = completionItem.DisplayText;
if (provideParenthesisCompletion)
{
insertText += "()";
CompletionProvidersLogger.LogCustomizedCommitToAddParenthesis(commitKey);
}
if (await ShouldCompleteWithFullyQualifyTypeName().ConfigureAwait(false))
{
var completionText = $"{containingNamespace}.{insertText}";
return(CompletionChange.Create(new TextChange(completionItem.Span, completionText)));
}
// Find context node so we can use it to decide where to insert using/imports.
var tree = await document.GetRequiredSyntaxTreeAsync(cancellationToken).ConfigureAwait(false);
var root = await tree.GetRootAsync(cancellationToken).ConfigureAwait(false);
var addImportContextNode = root.FindToken(completionItem.Span.Start, findInsideTrivia: true).Parent;
// Add required using/imports directive.
var addImportService = document.GetRequiredLanguageService <IAddImportsService>();
var generator = document.GetRequiredLanguageService <SyntaxGenerator>();
var addImportsOptions = await AddImportPlacementOptions.FromDocumentAsync(document, cancellationToken).ConfigureAwait(false);
var formattingOptions = await SyntaxFormattingOptions.FromDocumentAsync(document, cancellationToken).ConfigureAwait(false);
var importNode = CreateImport(document, containingNamespace);
var compilation = await document.Project.GetRequiredCompilationAsync(cancellationToken).ConfigureAwait(false);
var rootWithImport = addImportService.AddImport(compilation, root, addImportContextNode !, importNode, generator, addImportsOptions, cancellationToken);
var documentWithImport = document.WithSyntaxRoot(rootWithImport);
// This only formats the annotated import we just added, not the entire document.
var formattedDocumentWithImport = await Formatter.FormatAsync(documentWithImport, Formatter.Annotation, formattingOptions, cancellationToken).ConfigureAwait(false);
using var _ = ArrayBuilder <TextChange> .GetInstance(out var builder);
// Get text change for add import
var importChanges = await formattedDocumentWithImport.GetTextChangesAsync(document, cancellationToken).ConfigureAwait(false);
builder.AddRange(importChanges);
// Create text change for complete type name.
//
// Note: Don't try to obtain TextChange for completed type name by replacing the text directly,
// then use Document.GetTextChangesAsync on document created from the changed text. This is
// because it will do a diff and return TextChanges with minimum span instead of actual
// replacement span.
//
// For example: If I'm typing "asd", the completion provider could be triggered after "a"
// is typed. Then if I selected type "AsnEncodedData" to commit, by using the approach described
// above, we will get a TextChange of "AsnEncodedDat" with 0 length span, instead of a change of
// the full display text with a span of length 1. This will later mess up span-tracking and end up
// with "AsnEncodedDatasd" in the code.
builder.Add(new TextChange(completionItem.Span, insertText));
// Then get the combined change
var text = await document.GetTextAsync(cancellationToken).ConfigureAwait(false);
var newText = text.WithChanges(builder);
var changes = builder.ToImmutable();
var change = Utilities.Collapse(newText, changes);
return(CompletionChange.Create(change, changes));
async Task <bool> ShouldCompleteWithFullyQualifyTypeName()
{
if (!IsAddingImportsSupported(document))
{
return(true);
}
// We might need to qualify unimported types to use them in an import directive, because they only affect members of the containing
// import container (e.g. namespace/class/etc. declarations).
//
// For example, `List` and `StringBuilder` both need to be fully qualified below:
//
// using CollectionOfStringBuilders = System.Collections.Generic.List<System.Text.StringBuilder>;
//
// However, if we are typing in an C# using directive that is inside a nested import container (i.e. inside a namespace declaration block),
// then we can add an using in the outer import container instead (this is not allowed in VB).
//
// For example:
//
// using System.Collections.Generic;
// using System.Text;
//
// namespace Foo
// {
// using CollectionOfStringBuilders = List<StringBuilder>;
// }
//
// Here we will always choose to qualify the unimported type, just to be consistent and keeps things simple.
return(await IsInImportsDirectiveAsync(document, completionItem.Span.Start, cancellationToken).ConfigureAwait(false));
}
}
