/// <summary>
/// Returns the TokenIndex for the last token in the given file, or null if no such token exists.
/// Throws an ArgumentNullException if file is null.
/// </summary>
internal static CodeFragment.TokenIndex LastToken(this FileContentManager file)
{
if (file == null)
{
throw new ArgumentNullException(nameof(file));
}
var lastNonEmpty = file.NrLines();
while (lastNonEmpty-- > 0 && file.GetTokenizedLine(lastNonEmpty).Length == 0)
{
;
}
return(lastNonEmpty < 0
? null
: new CodeFragment.TokenIndex(file, lastNonEmpty, file.GetTokenizedLine(lastNonEmpty).Length - 1));
}
// the actual update routine
/// <summary>
/// Attempts to perform the necessary updates when replacing the range [start, start + count) by newText for the given file
/// wrapping each step in a QsCompilerError.RaiseOnFailure.
/// </summary>
private static void Update(this FileContentManager file, int start, int count, IEnumerable <string> newText)
{
CodeLine[] replacements = QsCompilerError.RaiseOnFailure(
() => ComputeCodeLines(newText, start > 0 ? file.GetLine(start - 1) : null).ToArray(),
"scope tracking update failed during computing the replacements");
IEnumerable <CodeLine>?updateRemaining = QsCompilerError.RaiseOnFailure(
() => ComputeUpdates(file, start, count, replacements),
"scope tracking update failed during computing the updates");
QsCompilerError.RaiseOnFailure(
() =>
{
if (updateRemaining == null)
{
file.ContentUpdate(start, count, replacements);
}
else
{
file.ContentUpdate(start, file.NrLines() - start, replacements.Concat(updateRemaining).ToArray());
}
},
"the proposed ContentUpdate failed");
QsCompilerError.RaiseOnFailure(
() =>
{
if (updateRemaining == null)
{
file.AddScopeDiagnostics(file.ComputeScopeDiagnostics(start, replacements.Length));
}
else
{
file.AddScopeDiagnostics(file.ComputeScopeDiagnostics(start));
}
file.AddScopeDiagnostics(file.CheckForMissingClosings());
},
"updating the scope diagnostics failed");
}
/// <summary> /// Computes excess bracket errors for the given range of lines in file based on the corresponding CodeLine. /// Throws an ArgumentOutOfRangeException if start is not within file. /// </summary> private static IEnumerable <Diagnostic> ComputeScopeDiagnostics(this FileContentManager file, int start) => ComputeScopeDiagnostics(file, start, file == null ? 0 : file.NrLines() - start);
/// <summary>
/// Computes excess bracket errors for the given range of lines in file based on the corresponding CodeLine.
/// Throws an ArgumentNullException if file is null.
/// Throws an ArgumentOutOfRangeException if start is not within file.
/// </summary>
private static IEnumerable <Diagnostic> ComputeScopeDiagnostics(this FileContentManager file, int start)
{
return(ComputeScopeDiagnostics(file, start, file == null ? 0 : file.NrLines() - start));
} // will raise an exception if file is null
/// <summary>
/// Extracts the code fragments based on the current file content that need to be re-processed due to content changes on the given lines.
/// Ignores any whitespace or comments at the beginning of the file (whether they have changed or not).
/// Ignores any whitespace or comments that occur after the last piece of code in the file.
/// Throws an ArgumentNullException if any of the arguments is null.
/// </summary>
private static IEnumerable <CodeFragment> FragmentsToProcess(this FileContentManager file, SortedSet <int> changedLines)
{
// NOTE: I suggest not to touch this routine unless absolutely necessary...(things *will* break)
if (file == null)
{
throw new ArgumentNullException(nameof(file));
}
if (changedLines == null)
{
throw new ArgumentNullException(nameof(changedLines));
}
var iter = changedLines.GetEnumerator();
var lastInFile = LastInFile(file);
Position processed = new Position(0, 0);
while (iter.MoveNext())
{
QsCompilerError.Verify(iter.Current >= 0 && iter.Current < file.NrLines(), "index out of range for changed line");
if (processed.Line < iter.Current)
{
var statementStart = file.PositionAfterPrevious(new Position(iter.Current, 0));
if (processed.IsSmallerThan(statementStart))
{
processed = statementStart;
}
}
while (processed.Line <= iter.Current && processed.IsSmallerThan(lastInFile))
{
processed = processed.Copy(); // because we don't want to modify the ending of the previous code fragment ...
var nextEnding = file.FragmentEnd(ref processed);
var extractedPiece = file.GetCodeSnippet(new LSP.Range {
Start = processed, End = nextEnding
});
// constructing the CodeFragment -
// NOTE: its Range.End is the position of the delimiting char (if such a char exists), i.e. the position right after Code ends
// length = 0 can occur e.g. if the last piece of code in the file does not terminate with a statement ending
if (extractedPiece.Length > 0)
{
var code = file.GetLine(nextEnding.Line).ExcessBracketPositions.Contains(nextEnding.Character - 1)
? extractedPiece.Substring(0, extractedPiece.Length - 1)
: extractedPiece;
if (code.Length == 0 || !CodeFragment.DelimitingChars.Contains(code.Last()))
{
code = $"{code}{CodeFragment.MissingDelimiter}";
}
var endChar = nextEnding.Character - (extractedPiece.Length - code.Length) - 1;
var codeRange = new LSP.Range {
Start = processed, End = new Position(nextEnding.Line, endChar)
};
yield return(new CodeFragment(file.IndentationAt(codeRange.Start), codeRange, code.Substring(0, code.Length - 1), code.Last()));
}
processed = nextEnding;
}
}
}
// routine(s) called by the FileContentManager upon updating a file
/// <summary>
/// Attempts to compute an incremental update for the change specified by start, count and newText, and updates file accordingly.
/// The given argument newText replaces the entire lines from start to (but not including) start + count.
/// If the given change is null, then (only) the currently queued unprocessed changes are processed.
/// Throws an ArgumentNullException if file is null.
/// Any other exceptions should be throws (and caught, and possibly re-thrown) during the updating.
/// </summary>
internal static void UpdateScopeTacking(this FileContentManager file, TextDocumentContentChangeEvent change)
{
if (file == null)
{
throw new ArgumentNullException(nameof(file));
}
/// <summary>
/// Replaces the lines in the range [start, end] with those for the given text.
/// </summary>
void ComputeUpdate(int start, int end, string text)
{
QsCompilerError.Verify(start >= 0 && end >= start && end < file.NrLines(), "invalid range for update");
// since both LF and CR in VS cause a line break on their own,
// we need to check if the change causes subequent CR LF to merge into a single line break
if (text.StartsWith(Utils.LF) && start > 0 && file.GetLine(start - 1).Text.EndsWith(Utils.CR))
{
text = file.GetLine(--start).Text + text;
}
// we need to check if the change causes the next line to merge with the (last) changed line
if (end + 1 < file.NrLines() && !Utils.EndOfLine.Match(text).Success)
{
text = text + file.GetLine(++end).Text;
}
var newLines = Utils.SplitLines(text);
var count = end - start + 1;
// note that the last line in the file won't end with a line break,
// and is hence only captured by SplitLines if it is not empty
// -> we therefore manually add the last line in the file if it is empty
if (newLines.Length == 0 || // the case if the file will be empty after the update
(start + count == file.NrLines() && Utils.EndOfLine.Match(newLines.Last()).Success))
{
newLines = newLines.Concat(new string[] { string.Empty }).ToArray();
}
QsCompilerError.Verify(newLines.Any(), "should have at least one line to replace");
file.Update(start, count, newLines);
}
file.SyncRoot.EnterUpgradeableReadLock();
try
{
// process the currently queued changes if necessary
if (file.DequeueUnprocessedChanges(out int start, out string text))
{
ComputeUpdate(start, start, text);
}
// process the given change if necessary
if (change != null)
{
ComputeUpdate(change.Range.Start.Line, change.Range.End.Line, Utils.GetTextChangedLines(file, change));
}
}
finally
{
file.SyncRoot.ExitUpgradeableReadLock();
}
}