sources property
A mapping from source URIs to directly reachable source URIs. For
example, a file "foo.dart" that imports "bar.dart" would have the
corresponding mapping { "file:///foo.dart" : "file:///bar.dart" }. If
"bar.dart" has further imports (or exports) there will be a mapping from
the URI "file:///bar.dart" to them. To check if a specific URI is
reachable from a given file, clients can check for its presence in the
resulting key set.
Implementation
Map<String, List<String>> sources;