internal static async Task <SyntaxNode> GetTransformedSyntaxRootAsync(
ISyntaxFacts syntaxFacts,
AbstractFileHeaderHelper fileHeaderHelper,
SyntaxTrivia newLineTrivia,
Document document,
CancellationToken cancellationToken
)
{
var tree = await document
.GetRequiredSyntaxTreeAsync(cancellationToken)
.ConfigureAwait(false);
var root = await tree.GetRootAsync(cancellationToken).ConfigureAwait(false);
if (
!document.Project.AnalyzerOptions.TryGetEditorConfigOption <string>(
CodeStyleOptions2.FileHeaderTemplate,
tree,
out var fileHeaderTemplate
) || string.IsNullOrEmpty(fileHeaderTemplate)
)
{
// This exception would show up as a gold bar, but as indicated we do not believe this is reachable.
throw ExceptionUtilities.Unreachable;
}
var expectedFileHeader = fileHeaderTemplate.Replace(
"{fileName}",
Path.GetFileName(document.FilePath)
);
var fileHeader = fileHeaderHelper.ParseFileHeader(root);
SyntaxNode newSyntaxRoot;
if (fileHeader.IsMissing)
{
newSyntaxRoot = AddHeader(
syntaxFacts,
fileHeaderHelper,
newLineTrivia,
root,
expectedFileHeader
);
}
else
{
newSyntaxRoot = ReplaceHeader(
syntaxFacts,
fileHeaderHelper,
newLineTrivia,
root,
expectedFileHeader
);
}
return(newSyntaxRoot);
}
private static SyntaxNode AddHeader(
ISyntaxFacts syntaxFacts,
AbstractFileHeaderHelper fileHeaderHelper,
SyntaxTrivia newLineTrivia,
SyntaxNode root,
string expectedFileHeader
)
{
var newTrivia = CreateNewHeader(
syntaxFacts,
fileHeaderHelper.CommentPrefix,
expectedFileHeader,
newLineTrivia.ToFullString()
)
.Add(newLineTrivia)
.Add(newLineTrivia);
// Skip blank lines already at the beginning of the document, since we add our own
var leadingTrivia = root.GetLeadingTrivia();
var skipCount = 0;
for (var i = 0; i < leadingTrivia.Count; i++)
{
if (leadingTrivia[i].RawKind == syntaxFacts.SyntaxKinds.EndOfLineTrivia)
{
skipCount = i + 1;
}
else if (leadingTrivia[i].RawKind != syntaxFacts.SyntaxKinds.WhitespaceTrivia)
{
break;
}
}
newTrivia = newTrivia.AddRange(leadingTrivia.Skip(skipCount));
return(root.WithLeadingTrivia(newTrivia));
}
internal static async Task <SyntaxNode> GetTransformedSyntaxRootAsync(ISyntaxFacts syntaxFacts, AbstractFileHeaderHelper fileHeaderHelper, SyntaxTrivia newLineTrivia, Document document, string?fileHeaderTemplate, CancellationToken cancellationToken)
{
var tree = await document.GetRequiredSyntaxTreeAsync(cancellationToken).ConfigureAwait(false);
var root = await tree.GetRootAsync(cancellationToken).ConfigureAwait(false);
// If we weren't given a header lets get the one from editorconfig
if (fileHeaderTemplate is null &&
!document.Project.AnalyzerOptions.AnalyzerConfigOptionsProvider.GetOptions(tree).TryGetEditorConfigOption(CodeStyleOptions2.FileHeaderTemplate, out fileHeaderTemplate))
{
// No header supplied, no editorconfig setting, nothing to do
return(root);
}
if (RoslynString.IsNullOrEmpty(fileHeaderTemplate))
{
// Header template is empty, nothing to do. This shouldn't be possible if this method is called in
// reaction to a diagnostic, but this method is also used when creating new documents so lets be defensive.
return(root);
}
var expectedFileHeader = fileHeaderTemplate.Replace("{fileName}", Path.GetFileName(document.FilePath));
var fileHeader = fileHeaderHelper.ParseFileHeader(root);
SyntaxNode newSyntaxRoot;
if (fileHeader.IsMissing)
{
newSyntaxRoot = AddHeader(syntaxFacts, fileHeaderHelper, newLineTrivia, root, expectedFileHeader);
}
else
{
newSyntaxRoot = ReplaceHeader(syntaxFacts, fileHeaderHelper, newLineTrivia, root, expectedFileHeader);
}
return(newSyntaxRoot);
}
private static SyntaxNode ReplaceHeader(ISyntaxFacts syntaxFacts, AbstractFileHeaderHelper fileHeaderHelper, SyntaxTrivia newLineTrivia, SyntaxNode root, string expectedFileHeader)
{
// Skip single line comments, whitespace, and end of line trivia until a blank line is encountered.
var triviaList = root.GetLeadingTrivia();
// True if the current line is blank so far (empty or whitespace); otherwise, false. The first line is
// assumed to not be blank, which allows the analysis to detect a file header which follows a blank line at
// the top of the file.
var onBlankLine = false;
// The set of indexes to remove from 'triviaList'. After removing these indexes, the remaining trivia (if
// any) will be preserved in the document along with the replacement header.
var removalList = new List <int>();
// The number of spaces to indent the new header. This is expected to match the indentation of the header
// which is being replaced.
var leadingSpaces = string.Empty;
// The number of spaces found so far on the current line. This will become 'leadingSpaces' if the spaces are
// followed by a comment which is considered a header comment.
var possibleLeadingSpaces = string.Empty;
// Need to do this with index so we get the line endings correct.
for (var i = 0; i < triviaList.Count; i++)
{
var triviaLine = triviaList[i];
if (triviaLine.RawKind == syntaxFacts.SyntaxKinds.SingleLineCommentTrivia)
{
if (possibleLeadingSpaces != string.Empty)
{
// One or more spaces precedes the comment. Keep track of these spaces so we can indent the new
// header by the same amount.
leadingSpaces = possibleLeadingSpaces;
}
removalList.Add(i);
onBlankLine = false;
}
else if (triviaLine.RawKind == syntaxFacts.SyntaxKinds.WhitespaceTrivia)
{
if (leadingSpaces == string.Empty)
{
possibleLeadingSpaces = triviaLine.ToFullString();
}
removalList.Add(i);
}
else if (triviaLine.RawKind == syntaxFacts.SyntaxKinds.EndOfLineTrivia)
{
possibleLeadingSpaces = string.Empty;
removalList.Add(i);
if (onBlankLine)
{
break;
}
else
{
onBlankLine = true;
}
}
else
{
break;
}
}
// Remove copyright lines in reverse order.
for (var i = removalList.Count - 1; i >= 0; i--)
{
triviaList = triviaList.RemoveAt(removalList[i]);
}
var newHeaderTrivia = CreateNewHeader(syntaxFacts, leadingSpaces + fileHeaderHelper.CommentPrefix, expectedFileHeader, newLineTrivia.ToFullString());
// Add a blank line and any remaining preserved trivia after the header.
newHeaderTrivia = newHeaderTrivia.Add(newLineTrivia).Add(newLineTrivia).AddRange(triviaList);
// Insert header at top of the file.
return(root.WithLeadingTrivia(newHeaderTrivia));
}