private static List <TextChange> AdjustRazorIndentation(FormattingContext context)
{
// Assume HTML formatter has already run at this point and HTML is relatively indented correctly.
// But HTML doesn't know about Razor blocks.
// Our goal here is to indent each line according to the surrounding Razor blocks.
var sourceText = context.SourceText;
var editsToApply = new List <TextChange>();
var indentations = context.GetIndentations();
for (var i = 0; i < sourceText.Lines.Count; i++)
{
var line = sourceText.Lines[i];
if (line.Span.Length == 0)
{
// Empty line.
continue;
}
if (indentations[i].StartsInCSharpContext)
{
// Normally we don't do HTML things in C# contexts but there is one
// edge case when including render fragments in a C# code block, eg:
//
// @code {
// void Foo()
// {
// Render(@<SurveyPrompt />);
// {
// }
//
// This is popular in some libraries, like bUnit. The issue here is that
// the HTML formatter sees ~~~~~<SurveyPrompt /> and puts a newline before
// the tag, but obviously that breaks things.
//
// It's straight forward enough to just check for this situation and special case
// it by removing the newline again.
// There needs to be at least one more line, and the current line needs to end with
// an @ sign, and have an open angle bracket at the start of the next line.
if (sourceText.Lines.Count >= i + 1 &&
line.Text?.Length > 1 &&
line.Text?[line.End - 1] == '@')
{
var nextLine = sourceText.Lines[i + 1];
var firstChar = nextLine.GetFirstNonWhitespaceOffset().GetValueOrDefault();
// When the HTML formatter inserts the newline in this scenario, it doesn't
// indent the component tag, so we use that as another signal that this is
// the scenario we think it is.
if (firstChar == 0 &&
nextLine.Text?[nextLine.Start] == '<')
{
var lineBreakLength = line.EndIncludingLineBreak - line.End;
var spanToReplace = new TextSpan(line.End, lineBreakLength);
var change = new TextChange(spanToReplace, string.Empty);
editsToApply.Add(change);
// Skip the next line because we've essentially just removed it.
i++;
}
}
continue;
}
var razorDesiredIndentationLevel = indentations[i].RazorIndentationLevel;
if (razorDesiredIndentationLevel == 0)
{
// This line isn't under any Razor specific constructs. Trust the HTML formatter.
continue;
}
var htmlDesiredIndentationLevel = indentations[i].HtmlIndentationLevel;
if (htmlDesiredIndentationLevel == 0 && !IsPartOfHtmlTag(context, indentations[i].FirstSpan.Span.Start))
{
// This line is under some Razor specific constructs but not under any HTML tag.
// E.g,
// @{
// @* comment *@ <----
// }
//
// In this case, the HTML formatter wouldn't touch it but we should format it correctly.
// So, let's use our syntax understanding to rewrite the indentation.
// Note: This case doesn't apply for HTML tags (HTML formatter will touch it even if it is in the root).
// Hence the second part of the if condition.
//
var desiredIndentationLevel = indentations[i].IndentationLevel;
var desiredIndentationString = context.GetIndentationLevelString(desiredIndentationLevel);
var spanToReplace = new TextSpan(line.Start, indentations[i].ExistingIndentation);
var change = new TextChange(spanToReplace, desiredIndentationString);
editsToApply.Add(change);
}
else
{
// This line is under some Razor specific constructs and HTML tags.
// E.g,
// @{
// <div class="foo"
// id="oof"> <----
// </div>
// }
//
// In this case, the HTML formatter would've formatted it correctly. Let's not use our syntax understanding.
// Instead, we should just add to the existing indentation.
//
var razorDesiredIndentationString = context.GetIndentationLevelString(razorDesiredIndentationLevel);
var existingIndentationString = context.GetIndentationString(indentations[i].ExistingIndentationSize);
var desiredIndentationString = existingIndentationString + razorDesiredIndentationString;
var spanToReplace = new TextSpan(line.Start, indentations[i].ExistingIndentation);
var change = new TextChange(spanToReplace, desiredIndentationString);
editsToApply.Add(change);
}
}
return(editsToApply);
}
protected async Task <List <TextChange> > AdjustIndentationAsync(FormattingContext context, CancellationToken cancellationToken, Range?range = null)
{
// In this method, the goal is to make final adjustments to the indentation of each line.
// We will take into account the following,
// 1. The indentation due to nested C# structures
// 2. The indentation due to Razor and HTML constructs
var text = context.SourceText;
range ??= TextSpan.FromBounds(0, text.Length).AsRange(text);
// To help with figuring out the correct indentation, first we will need the indentation
// that the C# formatter wants to apply in the following locations,
// 1. The start and end of each of our source mappings
// 2. The start of every line that starts in C# context
// Due to perf concerns, we only want to invoke the real C# formatter once.
// So, let's collect all the significant locations that we want to obtain the CSharpDesiredIndentations for.
var significantLocations = new HashSet <int>();
// First, collect all the locations at the beginning and end of each source mapping.
var sourceMappingMap = new Dictionary <int, int>();
foreach (var mapping in context.CodeDocument.GetCSharpDocument().SourceMappings)
{
var mappingSpan = new TextSpan(mapping.OriginalSpan.AbsoluteIndex, mapping.OriginalSpan.Length);
if (!ShouldFormat(context, mappingSpan, allowImplicitStatements: true))
{
// We don't care about this range as this can potentially lead to incorrect scopes.
continue;
}
var originalStartLocation = mapping.OriginalSpan.AbsoluteIndex;
var projectedStartLocation = mapping.GeneratedSpan.AbsoluteIndex;
sourceMappingMap[originalStartLocation] = projectedStartLocation;
significantLocations.Add(projectedStartLocation);
var originalEndLocation = mapping.OriginalSpan.AbsoluteIndex + mapping.OriginalSpan.Length + 1;
var projectedEndLocation = mapping.GeneratedSpan.AbsoluteIndex + mapping.GeneratedSpan.Length + 1;
sourceMappingMap[originalEndLocation] = projectedEndLocation;
significantLocations.Add(projectedEndLocation);
}
// Next, collect all the line starts that start in C# context
var indentations = context.GetIndentations();
var lineStartMap = new Dictionary <int, int>();
for (var i = range.Start.Line; i <= range.End.Line; i++)
{
if (indentations[i].EmptyOrWhitespaceLine)
{
// We should remove whitespace on empty lines.
continue;
}
var line = context.SourceText.Lines[i];
var lineStart = line.GetFirstNonWhitespacePosition() ?? line.Start;
var lineStartSpan = new TextSpan(lineStart, 0);
if (!ShouldFormat(context, lineStartSpan, allowImplicitStatements: true))
{
// We don't care about this range as this can potentially lead to incorrect scopes.
continue;
}
if (DocumentMappingService.TryMapToProjectedDocumentPosition(context.CodeDocument, lineStart, out _, out var projectedLineStart))
{
lineStartMap[lineStart] = projectedLineStart;
significantLocations.Add(projectedLineStart);
}
}
// Now, invoke the C# formatter to obtain the CSharpDesiredIndentation for all significant locations.
var significantLocationIndentation = await CSharpFormatter.GetCSharpIndentationAsync(context, significantLocations, cancellationToken);
// Build source mapping indentation scopes.
var sourceMappingIndentations = new SortedDictionary <int, int>();
foreach (var originalLocation in sourceMappingMap.Keys)
{
var significantLocation = sourceMappingMap[originalLocation];
if (!significantLocationIndentation.TryGetValue(significantLocation, out var indentation))
{
// C# formatter didn't return an indentation for this. Skip.
continue;
}
sourceMappingIndentations[originalLocation] = indentation;
}
var sourceMappingIndentationScopes = sourceMappingIndentations.Keys.ToArray();
// Build lineStart indentation map.
var lineStartIndentations = new Dictionary <int, int>();
foreach (var originalLocation in lineStartMap.Keys)
{
var significantLocation = lineStartMap[originalLocation];
if (!significantLocationIndentation.TryGetValue(significantLocation, out var indentation))
{
// C# formatter didn't return an indentation for this. Skip.
continue;
}
lineStartIndentations[originalLocation] = indentation;
}
// Now, let's combine the C# desired indentation with the Razor and HTML indentation for each line.
var newIndentations = new Dictionary <int, int>();
for (var i = range.Start.Line; i <= range.End.Line; i++)
{
if (indentations[i].EmptyOrWhitespaceLine)
{
// We should remove whitespace on empty lines.
newIndentations[i] = 0;
continue;
}
var minCSharpIndentation = context.GetIndentationOffsetForLevel(indentations[i].MinCSharpIndentLevel);
var line = context.SourceText.Lines[i];
var lineStart = line.GetFirstNonWhitespacePosition() ?? line.Start;
var lineStartSpan = new TextSpan(lineStart, 0);
if (!ShouldFormat(context, lineStartSpan, allowImplicitStatements: true))
{
// We don't care about this line as it lies in an area we don't want to format.
continue;
}
if (!lineStartIndentations.TryGetValue(lineStart, out var csharpDesiredIndentation))
{
// Couldn't remap. This is probably a non-C# location.
// Use SourceMapping indentations to locate the C# scope of this line.
// E.g,
//
// @if (true) {
// <div>
// |</div>
// }
//
// We can't find a direct mapping at |, but we can infer its base indentation from the
// indentation of the latest source mapping prior to this line.
// We use binary search to find that spot.
var index = Array.BinarySearch(sourceMappingIndentationScopes, lineStart);
if (index < 0)
{
// Couldn't find the exact value. Find the index of the element to the left of the searched value.
index = (~index) - 1;
}
if (index < 0)
{
// If we _still_ couldn't find the right indentation, then it probably means that the text is
// before the first source mapping location, so we can just place it in the minimum spot (realistically
// at index 0 in the razor file, but we use minCSharpIndentation because we're adjusting based on the
// generated file here)
csharpDesiredIndentation = minCSharpIndentation;
}
else
{
// index will now be set to the same value as the end of the closest source mapping.
var absoluteIndex = sourceMappingIndentationScopes[index];
csharpDesiredIndentation = sourceMappingIndentations[absoluteIndex];
// This means we didn't find an exact match and so we used the indentation of the end of a previous mapping.
// So let's use the MinCSharpIndentation of that same location if possible.
if (context.TryGetFormattingSpan(absoluteIndex, out var span))
{
minCSharpIndentation = context.GetIndentationOffsetForLevel(span.MinCSharpIndentLevel);
}
}
}
// Now let's use that information to figure out the effective C# indentation.
// This should be based on context.
// For instance, lines inside @code/@functions block should be reduced one level
// and lines inside @{} should be reduced by two levels.
if (csharpDesiredIndentation < minCSharpIndentation)
{
// CSharp formatter doesn't want to indent this. Let's not touch it.
continue;
}
var effectiveCSharpDesiredIndentation = csharpDesiredIndentation - minCSharpIndentation;
var razorDesiredIndentation = context.GetIndentationOffsetForLevel(indentations[i].IndentationLevel);
if (indentations[i].StartsInHtmlContext)
{
// This is a non-C# line.
if (context.IsFormatOnType)
{
// HTML formatter doesn't run in the case of format on type.
// Let's stick with our syntax understanding of HTML to figure out the desired indentation.
}
else
{
// Given that the HTML formatter ran before this, we can assume
// HTML is already correctly formatted. So we can use the existing indentation as is.
// We need to make sure to use the indentation size, as this will get passed to
// GetIndentationString eventually.
razorDesiredIndentation = indentations[i].ExistingIndentationSize;
}
}
var effectiveDesiredIndentation = razorDesiredIndentation + effectiveCSharpDesiredIndentation;
// This will now contain the indentation we ultimately want to apply to this line.
newIndentations[i] = effectiveDesiredIndentation;
}
// Now that we have collected all the indentations for each line, let's convert them to text edits.
var changes = new List <TextChange>();
foreach (var item in newIndentations)
{
var line = item.Key;
var indentation = item.Value;
Debug.Assert(indentation >= 0, "Negative indentation. This is unexpected.");
var existingIndentationLength = indentations[line].ExistingIndentation;
var spanToReplace = new TextSpan(context.SourceText.Lines[line].Start, existingIndentationLength);
var effectiveDesiredIndentation = context.GetIndentationString(indentation);
changes.Add(new TextChange(spanToReplace, effectiveDesiredIndentation));
}
return(changes);
}
private static void CleanupSourceMappingEnd(FormattingContext context, Range sourceMappingRange, List <TextChange> changes, bool newLineWasAddedAtStart)
{
//
// We look through every source mapping that intersects with the affected range and
// bring the content after the last line to its own line and adjust its indentation,
//
// E.g,
//
// @{
// if (true)
// { <div></div>
// }
// }
//
// becomes,
//
// @{
// if (true)
// {
// </div></div>
// }
// }
//
var text = context.SourceText;
var sourceMappingSpan = sourceMappingRange.AsTextSpan(text);
var mappingEndLineIndex = sourceMappingRange.End.Line;
var indentations = context.GetIndentations();
var startsInCSharpContext = indentations[mappingEndLineIndex].StartsInCSharpContext;
// If the span is on a single line, and we added a line, then end point is now on a line that does start in a C# context.
if (!startsInCSharpContext && newLineWasAddedAtStart && sourceMappingRange.Start.Line == mappingEndLineIndex)
{
startsInCSharpContext = true;
}
if (!startsInCSharpContext)
{
// For corner cases like (Position marked with |),
// It is already in a separate line. It doesn't need cleaning up.
// @{
// if (true}
// {
// |<div></div>
// }
// }
//
return;
}
var endSpan = TextSpan.FromBounds(sourceMappingSpan.End, sourceMappingSpan.End);
if (!ShouldFormat(context, endSpan, allowImplicitStatements: false))
{
// We don't want to run cleanup on this range.
return;
}
var contentStartOffset = text.Lines[mappingEndLineIndex].GetFirstNonWhitespaceOffset(sourceMappingRange.End.Character);
if (contentStartOffset is null)
{
// There is no content after the end of this source mapping. No need to clean up.
return;
}
var spanToReplace = new TextSpan(sourceMappingSpan.End, 0);
if (!context.TryGetIndentationLevel(spanToReplace.End, out var contentIndentLevel))
{
// Can't find the correct indentation for this content. Leave it alone.
return;
}
// At this point, `contentIndentLevel` should contain the correct indentation level for `}` in the above example.
var replacement = context.NewLineString + context.GetIndentationLevelString(contentIndentLevel);
// After the below change the above example should look like,
// @{
// if (true)
// {
// <div></div>
// }
// }
var change = new TextChange(spanToReplace, replacement);
changes.Add(change);
}
