private static async Task <TextEdit[]> GetFormattedCSharpEditsAsync(
RazorCodeDocument codeDocument,
char typedChar,
int position,
bool insertSpaces,
int tabSize)
{
var generatedCode = codeDocument.GetCSharpDocument().GeneratedCode;
var csharpSourceText = SourceText.From(generatedCode);
var document = GenerateRoslynCSharpDocument(csharpSourceText);
var documentOptions = await GetDocumentOptionsAsync(document, insertSpaces, tabSize);
var formattingChanges = await RazorCSharpFormattingInteractionService.GetFormattingChangesAsync(
document, typedChar, position, documentOptions, CancellationToken.None).ConfigureAwait(false);
var textEdits = formattingChanges.Select(change => change.AsTextEdit(csharpSourceText)).ToArray();
return(textEdits);
Document GenerateRoslynCSharpDocument(SourceText csharpSourceText)
{
var workspace = TestWorkspace.Create();
var project = workspace.CurrentSolution.AddProject("TestProject", "TestAssembly", LanguageNames.CSharp);
var document = project.AddDocument("TestDocument", csharpSourceText);
return(document);
}
async Task <DocumentOptionSet> GetDocumentOptionsAsync(Document document, bool insertSpaces, int tabSize)
{
var documentOptions = await document.GetOptionsAsync().ConfigureAwait(false);
documentOptions = documentOptions.WithChangedOption(CodeAnalysis.Formatting.FormattingOptions.TabSize, tabSize)
.WithChangedOption(CodeAnalysis.Formatting.FormattingOptions.IndentationSize, tabSize)
.WithChangedOption(CodeAnalysis.Formatting.FormattingOptions.UseTabs, !insertSpaces);
return(documentOptions);
}
}
public async override Task <FormattingResult> ExecuteAsync(FormattingContext context, FormattingResult result, CancellationToken cancellationToken)
{
if (!context.IsFormatOnType || result.Kind != RazorLanguageKind.CSharp)
{
// We don't want to handle regular formatting or non-C# on type formatting here.
return(result);
}
// Normalize and re-map the C# edits.
var codeDocument = context.CodeDocument;
var csharpText = codeDocument.GetCSharpSourceText();
var textEdits = result.Edits;
if (textEdits.Length == 0)
{
if (!DocumentMappingService.TryMapToProjectedDocumentPosition(codeDocument, context.HostDocumentIndex, out _, out var projectedIndex))
{
_logger.LogWarning($"Failed to map to projected position for document {context.Uri}.");
return(result);
}
// Ask C# for formatting changes.
var indentationOptions = new RazorIndentationOptions(
UseTabs: !context.Options.InsertSpaces,
TabSize: context.Options.TabSize,
IndentationSize: context.Options.TabSize);
var autoFormattingOptions = new RazorAutoFormattingOptions(
formatOnReturn: true, formatOnTyping: true, formatOnSemicolon: true, formatOnCloseBrace: true);
var formattingChanges = await RazorCSharpFormattingInteractionService.GetFormattingChangesAsync(
context.CSharpWorkspaceDocument,
typedChar : context.TriggerCharacter,
projectedIndex,
indentationOptions,
autoFormattingOptions,
indentStyle : CodeAnalysis.Formatting.FormattingOptions.IndentStyle.Smart,
cancellationToken).ConfigureAwait(false);
if (formattingChanges.IsEmpty)
{
_logger.LogInformation("Received no results.");
return(result);
}
textEdits = formattingChanges.Select(change => change.AsTextEdit(csharpText)).ToArray();
_logger.LogInformation($"Received {textEdits.Length} results from C#.");
}
var normalizedEdits = NormalizeTextEdits(csharpText, textEdits, out var originalTextWithChanges);
var mappedEdits = RemapTextEdits(codeDocument, normalizedEdits, result.Kind);
var filteredEdits = FilterCSharpTextEdits(context, mappedEdits);
if (filteredEdits.Length == 0)
{
// There are no CSharp edits for us to apply. No op.
return(new FormattingResult(filteredEdits));
}
// Find the lines that were affected by these edits.
var originalText = codeDocument.GetSourceText();
var changes = filteredEdits.Select(e => e.AsTextChange(originalText));
// Apply the format on type edits sent over by the client.
var formattedText = ApplyChangesAndTrackChange(originalText, changes, out _, out var spanAfterFormatting);
var changedContext = await context.WithTextAsync(formattedText);
var rangeAfterFormatting = spanAfterFormatting.AsRange(formattedText);
cancellationToken.ThrowIfCancellationRequested();
// We make an optimistic attempt at fixing corner cases.
var cleanupChanges = CleanupDocument(changedContext, rangeAfterFormatting);
var cleanedText = formattedText.WithChanges(cleanupChanges);
changedContext = await changedContext.WithTextAsync(cleanedText);
cancellationToken.ThrowIfCancellationRequested();
// At this point we should have applied all edits that adds/removes newlines.
// Let's now ensure the indentation of each of those lines is correct.
// We only want to adjust the range that was affected.
// We need to take into account the lines affected by formatting as well as cleanup.
var lineDelta = LineDelta(formattedText, cleanupChanges, out var firstPosition, out var lastPosition);
// Okay hear me out, I know this looks lazy, but it totally makes sense.
// This method is called with edits that the C# formatter wants to make, and from those edits we work out which
// other edits to apply etc. Fine, all good so far. BUT its totally possible that the user typed a closing brace
// in the same position as the C# formatter thought it should be, on the line _after_ the code that the C# formatter
// reformatted.
//
// For example, given:
// if (true){
// }
//
// If the C# formatter is happy with the placement of that close brace then this method will get two edits:
// * On line 1 to indent the if by 4 spaces
// * On line 1 to add a newline and 4 spaces in front of the opening brace
//
// We'll happy format lines 1 and 2, and ignore the closing brace altogether. So, by looking one line further
// we won't have that problem.
if (rangeAfterFormatting.End.Line + lineDelta < cleanedText.Lines.Count)
{
lineDelta++;
}
// Now we know how many lines were affected by the cleanup and formatting, but we don't know where those lines are. For example, given:
//
// @if (true)
// {
// }
// else
// {
// $$}
//
// When typing that close brace, the changes would fix the previous close brace, but the line delta would be 0, so
// we'd format line 6 and call it a day, even though the formatter made an edit on line 3. To fix this we use the
// first and last position of edits made above, and make sure our range encompasses them as well. For convenience
// we calculate these positions in the LineDelta method called above.
// This is essentially: rangeToAdjust = new Range(Math.Min(firstFormattingEdit, userEdit), Math.Max(lastFormattingEdit, userEdit))
var start = rangeAfterFormatting.Start;
if (firstPosition is not null && firstPosition < start)
{
start = firstPosition;
}
var end = new Position(rangeAfterFormatting.End.Line + lineDelta, 0);
if (lastPosition is not null && lastPosition < start)
{
end = lastPosition;
}
var rangeToAdjust = new Range(start, end);
Debug.Assert(rangeToAdjust.End.IsValid(cleanedText), "Invalid range. This is unexpected.");
var indentationChanges = await AdjustIndentationAsync(changedContext, cancellationToken, rangeToAdjust);
if (indentationChanges.Count > 0)
{
// Apply the edits that modify indentation.
cleanedText = cleanedText.WithChanges(indentationChanges);
}
// Now that we have made all the necessary changes to the document. Let's diff the original vs final version and return the diff.
var finalChanges = cleanedText.GetTextChanges(originalText);
var finalEdits = finalChanges.Select(f => f.AsTextEdit(originalText)).ToArray();
if (context.AutomaticallyAddUsings)
{
// Because we need to parse the C# code twice for this operation, lets do a quick check to see if its even necessary
if (textEdits.Any(e => e.NewText.IndexOf("using") != -1))
{
finalEdits = await AddUsingStatementEditsAsync(codeDocument, finalEdits, csharpText, originalTextWithChanges, cancellationToken);
}
}
return(new FormattingResult(finalEdits));
}
