/// <summary>
/// Get the import strings for a given method, following forward pointers as necessary.
/// </summary>
/// <returns>
/// For each namespace enclosing the method, a list of import strings, innermost to outermost.
/// There should always be at least one entry, for the global namespace.
/// </returns>
public static ImmutableArray <ImmutableArray <string> > GetCSharpGroupedImportStrings(this ISymUnmanagedReader reader, int methodToken, int methodVersion, out ImmutableArray <string> externAliasStrings)
{
externAliasStrings = default(ImmutableArray <string>);
ImmutableArray <short> groupSizes = default(ImmutableArray <short>);
bool seenForward = false;
RETRY:
byte[] bytes = reader.GetCustomDebugInfoBytes(methodToken, methodVersion);
if (bytes == null)
{
return(default(ImmutableArray <ImmutableArray <string> >));
}
foreach (var record in GetCustomDebugInfoRecords(bytes))
{
switch (record.Kind)
{
case CustomDebugInfoKind.UsingInfo:
if (!groupSizes.IsDefault)
{
throw new InvalidOperationException(string.Format("Expected at most one Using record for method {0}", FormatMethodToken(methodToken)));
}
groupSizes = DecodeUsingRecord(record.Data);
break;
case CustomDebugInfoKind.ForwardInfo:
if (!externAliasStrings.IsDefault)
{
throw new InvalidOperationException(string.Format("Did not expect both Forward and ForwardToModule records for method {0}", FormatMethodToken(methodToken)));
}
methodToken = DecodeForwardRecord(record.Data);
// Follow at most one forward link (as in FUNCBRECEE::ensureNamespaces).
// NOTE: Dev11 may produce chains of forward links (e.g. for System.Collections.Immutable).
if (!seenForward)
{
seenForward = true;
goto RETRY;
}
break;
case CustomDebugInfoKind.ForwardToModuleInfo:
if (!externAliasStrings.IsDefault)
{
throw new InvalidOperationException(string.Format("Expected at most one ForwardToModule record for method {0}", FormatMethodToken(methodToken)));
}
int moduleInfoMethodToken = DecodeForwardToModuleRecord(record.Data);
ImmutableArray <string> allModuleInfoImportStrings = reader.GetMethodByVersion(moduleInfoMethodToken, methodVersion).GetImportStrings();
ArrayBuilder <string> externAliasBuilder = ArrayBuilder <string> .GetInstance();
foreach (string importString in allModuleInfoImportStrings)
{
if (IsCSharpExternAliasInfo(importString))
{
externAliasBuilder.Add(importString);
}
}
externAliasStrings = externAliasBuilder.ToImmutableAndFree();
break;
}
}
if (groupSizes.IsDefault)
{
// This can happen in malformed PDBs (e.g. chains of forwards).
return(default(ImmutableArray <ImmutableArray <string> >));
}
var method = reader.GetMethodByVersion(methodToken, methodVersion);
if (method == null)
{
return(default(ImmutableArray <ImmutableArray <string> >));
}
ImmutableArray <string> importStrings = method.GetImportStrings();
int numImportStrings = importStrings.Length;
ArrayBuilder <ImmutableArray <string> > resultBuilder = ArrayBuilder <ImmutableArray <string> > .GetInstance(groupSizes.Length);
ArrayBuilder <string> groupBuilder = ArrayBuilder <string> .GetInstance();
int pos = 0;
foreach (short groupSize in groupSizes)
{
for (int i = 0; i < groupSize; i++, pos++)
{
if (pos >= numImportStrings)
{
throw new InvalidOperationException(string.Format("Group size indicates more imports than there are import strings (method {0}).", FormatMethodToken(methodToken)));
}
string importString = importStrings[pos];
if (IsCSharpExternAliasInfo(importString))
{
throw new InvalidOperationException(string.Format("Encountered extern alias info before all import strings were consumed (method {0}).", FormatMethodToken(methodToken)));
}
groupBuilder.Add(importString);
}
resultBuilder.Add(groupBuilder.ToImmutable());
groupBuilder.Clear();
}
if (externAliasStrings.IsDefault)
{
Debug.Assert(groupBuilder.Count == 0);
// Extern alias detail strings (prefix "Z") are not included in the group counts.
for (; pos < numImportStrings; pos++)
{
string importString = importStrings[pos];
if (!IsCSharpExternAliasInfo(importString))
{
throw new InvalidOperationException(string.Format("Expected only extern alias info strings after consuming the indicated number of imports (method {0}).", FormatMethodToken(methodToken)));
}
groupBuilder.Add(importString);
}
externAliasStrings = groupBuilder.ToImmutableAndFree();
}
else
{
groupBuilder.Free();
if (pos < numImportStrings)
{
throw new InvalidOperationException(string.Format("Group size indicates fewer imports than there are import strings (method {0}).", FormatMethodToken(methodToken)));
}
}
return(resultBuilder.ToImmutableAndFree());
}
