/// <summary>
/// Return an enumerable of suitable edits to add open directives for all given namespaces for which no open directive already exists.
/// Returns an edit for opening a given namespace even if an alias is already defined for that namespace.
/// Returns an empty enumerable if suitable edits could not be determined.
/// </summary>
private static IEnumerable <TextEdit> OpenDirectiveSuggestions(this FileContentManager file, int lineNr, IEnumerable <string> namespaces)
{
// determine the first fragment in the containing namespace
var nsElements = file?.NamespaceDeclarationTokens()
.TakeWhile(t => t.Line <= lineNr).LastOrDefault() // going by line here is fine - inaccuracies if someone has multiple namespace and callable declarations on the same line seem acceptable...
?.GetChildren(deep: false);
var firstInNs = nsElements?.FirstOrDefault()?.GetFragment();
if (file is null || nsElements is null || firstInNs?.Kind == null)
{
return(Enumerable.Empty <TextEdit>());
}
// determine what open directives already exist
var insertOpenDirAt = firstInNs.Range.Start;
var openDirs = nsElements.SelectNotNull(t => t.GetFragment().Kind?.OpenedNamespace())
.TakeWhile(opened => opened.IsValue)
.Select(opened => (
opened.Item.Item1.Symbol.AsDeclarationName(null),
opened.Item.Item2.IsValue ? opened.Item.Item2.Item.Symbol.AsDeclarationName("") : null))
.Where(opened => opened.Item1 != null)
.GroupBy(opened => opened.Item1, opened => opened.Item2) // in case there are duplicate open directives...
.ToImmutableDictionary(opened => opened.Key, opened => opened.First());
// range and whitespace info for inserting open directives
var additionalLinesAfterOpenDir = firstInNs.Kind.OpenedNamespace().IsNull ? $"{Environment.NewLine}{Environment.NewLine}" : "";
var indentationAfterOpenDir = file.GetLine(insertOpenDirAt.Line).Text.Substring(0, insertOpenDirAt.Column);
var whitespaceAfterOpenDir = $"{Environment.NewLine}{additionalLinesAfterOpenDir}{(string.IsNullOrWhiteSpace(indentationAfterOpenDir) ? indentationAfterOpenDir : " ")}";
// construct a suitable edit
return(namespaces.Distinct().Where(ns => !openDirs.Contains(ns, null)).Select(suggestedNS => // filter all namespaces that are already open
{
var directive = $"{Keywords.importDirectiveHeader.id} {suggestedNS}";
return new TextEdit
{
Range = new Lsp.Range {
Start = insertOpenDirAt.ToLsp(), End = insertOpenDirAt.ToLsp()
},
NewText = $"{directive};{whitespaceAfterOpenDir}"
};
}));
}
