// internal for testing
internal ComparisonResult Compare(AssemblyIdentity reference, string referenceDisplayName, AssemblyIdentity definition, out bool unificationApplied, bool ignoreVersion)
{
Debug.Assert((reference != null) ^ (referenceDisplayName != null));
unificationApplied = false;
AssemblyIdentityParts parts;
if (reference != null)
{
// fast path
bool?eq = TriviallyEquivalent(reference, definition);
if (eq.HasValue)
{
return(eq.Value ? ComparisonResult.Equivalent : ComparisonResult.NotEquivalent);
}
parts = AssemblyIdentityParts.Name | AssemblyIdentityParts.Version | AssemblyIdentityParts.Culture | AssemblyIdentityParts.PublicKeyToken;
}
else
{
if (!AssemblyIdentity.TryParseDisplayName(referenceDisplayName, out reference, out parts) ||
reference.ContentType != definition.ContentType)
{
return(ComparisonResult.NotEquivalent);
}
}
Debug.Assert(reference.ContentType == definition.ContentType);
bool isDefinitionFxAssembly;
if (!ApplyUnificationPolicies(ref reference, ref definition, parts, out isDefinitionFxAssembly))
{
return(ComparisonResult.NotEquivalent);
}
if (ReferenceEquals(reference, definition))
{
return(ComparisonResult.Equivalent);
}
bool compareCulture = (parts & AssemblyIdentityParts.Culture) != 0;
bool comparePublicKeyToken = (parts & AssemblyIdentityParts.PublicKeyOrToken) != 0;
if (!definition.IsStrongName)
{
if (reference.IsStrongName)
{
return(ComparisonResult.NotEquivalent);
}
if (!AssemblyIdentity.IsFullName(parts))
{
if (!SimpleNameComparer.Equals(reference.Name, definition.Name))
{
return(ComparisonResult.NotEquivalent);
}
if (compareCulture && !CultureComparer.Equals(reference.CultureName, definition.CultureName))
{
return(ComparisonResult.NotEquivalent);
}
// version is ignored
return(ComparisonResult.Equivalent);
}
isDefinitionFxAssembly = false;
}
if (!SimpleNameComparer.Equals(reference.Name, definition.Name))
{
return(ComparisonResult.NotEquivalent);
}
if (compareCulture && !CultureComparer.Equals(reference.CultureName, definition.CultureName))
{
return(ComparisonResult.NotEquivalent);
}
if (comparePublicKeyToken && !AssemblyIdentity.KeysEqual(reference, definition))
{
return(ComparisonResult.NotEquivalent);
}
bool hasSomeVersionParts = (parts & AssemblyIdentityParts.Version) != 0;
bool hasPartialVersion = (parts & AssemblyIdentityParts.Version) != AssemblyIdentityParts.Version;
// If any version parts were specified then compare the versions. The comparison fails if some version parts are missing.
if (definition.IsStrongName &&
hasSomeVersionParts &&
(hasPartialVersion || reference.Version != definition.Version))
{
// Note:
// System.Numerics.Vectors, Version=4.0 is an FX assembly
// System.Numerics.Vectors, Version=4.1+ is not an FX assembly
//
// It seems like a bug in Fusion: it only determines whether the definition is an FX assembly
// and calculates the result based upon that, regardless of whether the reference is an FX assembly or not.
// We do replicate the behavior.
//
// As a result unification is asymmetric when comparing the above identities.
if (isDefinitionFxAssembly)
{
unificationApplied = true;
return(ComparisonResult.Equivalent);
}
if (ignoreVersion)
{
return(ComparisonResult.EquivalentIgnoringVersion);
}
return(ComparisonResult.NotEquivalent);
}
return(ComparisonResult.Equivalent);
}
internal override bool ApplyUnificationPolicies(
ref AssemblyIdentity reference,
ref AssemblyIdentity definition,
AssemblyIdentityParts referenceParts,
out bool isDefinitionFxAssembly)
{
if (reference.ContentType == AssemblyContentType.Default &&
SimpleNameComparer.Equals(reference.Name, definition.Name) &&
SimpleNameComparer.Equals(reference.Name, "mscorlib"))
{
isDefinitionFxAssembly = true;
reference = definition;
return(true);
}
if (!reference.IsRetargetable && definition.IsRetargetable)
{
// Reference is not retargetable, but definition is retargetable.
// Non-equivalent.
isDefinitionFxAssembly = false;
return(false);
}
// Notes:
// an assembly might be both retargetable and portable
// in that case retargetable table acts as an override.
// Apply portability policy transforms first (e.g. rewrites references to SL assemblies to their desktop equivalents)
// If the reference is partial and is missing version or PKT it is not ported.
reference = Port(reference);
definition = Port(definition);
if (reference.IsRetargetable && !definition.IsRetargetable)
{
if (!AssemblyIdentity.IsFullName(referenceParts))
{
isDefinitionFxAssembly = false;
return(false);
}
// Reference needs to be retargeted before comparison,
// unless it's optionally retargetable and we already match the PK
bool skipRetargeting = IsOptionallyRetargetableAssembly(reference) &&
AssemblyIdentity.KeysEqual(reference, definition);
if (!skipRetargeting)
{
reference = Retarget(reference);
}
}
// At this point we are in one of the following states:
//
// 1) Both ref/def are not retargetable
// 2) Both ref/def are retargetable
// 3) Ref is retargetable (and has been retargeted)
//
// We can do a straight compare of ref/def at this point using the
// regular rules
if (reference.IsRetargetable && definition.IsRetargetable)
{
isDefinitionFxAssembly = IsRetargetableAssembly(definition);
}
else
{
isDefinitionFxAssembly = IsFrameworkAssembly(definition);
}
return(true);
}
