public void ConcatCollidingExternAliases()
{
var comp = CreateCompilation(
"extern alias A; extern alias B;",
targetFramework: TargetFramework.Mscorlib40,
references: new[]
{
SystemCoreRef.WithAliases(new[] { "A" }),
SystemDataRef.WithAliases(new[] { "B" }),
}
);
var tree = comp.SyntaxTrees.Single();
var binder = comp.GetBinderFactory(tree)
.GetImportsBinder((CSharpSyntaxNode)tree.GetRoot(), inUsing: false);
var scratchImports = binder.GetImports(basesBeingResolved: null);
var scratchExternAliases = scratchImports.ExternAliases;
Assert.Equal(2, scratchExternAliases.Length);
var externAlias1 = scratchExternAliases[0];
var externAlias2 = new AliasAndExternAliasDirective(
AliasSymbol.CreateCustomDebugInfoAlias(
scratchExternAliases[1].Alias.Target,
externAlias1.ExternAliasDirective.Identifier,
binder
),
externAlias1.ExternAliasDirective
);
var imports1 = Imports.FromCustomDebugInfo(
comp,
ImmutableDictionary <string, AliasAndUsingDirective> .Empty,
ImmutableArray <NamespaceOrTypeAndUsingDirective> .Empty,
ImmutableArray.Create(externAlias1)
);
var imports2 = Imports.FromCustomDebugInfo(
comp,
ImmutableDictionary <string, AliasAndUsingDirective> .Empty,
ImmutableArray <NamespaceOrTypeAndUsingDirective> .Empty,
ImmutableArray.Create(externAlias2)
);
var concat1 = imports1.Concat(imports2);
Assert.Equal(externAlias2.Alias.Target, concat1.ExternAliases.Single().Alias.Target);
var concat2 = imports2.Concat(imports1);
Assert.Equal(externAlias1.Alias.Target, concat2.ExternAliases.Single().Alias.Target);
}
