Added dependency-graph example

examples/dependency-graph/__main__.py

@@ -0,0 +1,28 @@
+from os.path import basename, dirname, join
+
+from ..cli import (resolve_circular_references,  # type: ignore
+                   show_unresolved_dependencies)
+from ..config import FileConfig  # type: ignore
+from ..language import MakeDataConfig  # type: ignore
+from ..project_graph import ProjectGraph  # type: ignore
+from ..shell import failure, pretty_debug, success  # type: ignore
+
+
+def pretty_print_order(graph: ProjectGraph):
+	return ' -> '.join([basename(edge.project.directory) \
+					 if isinstance(edge.project, FileConfig) \
+						else str(edge) for edge in graph.traverse_dependencies()])
+
+master_project_path = join(dirname(__file__), "1-master-project")
+master_project = MakeDataConfig.of(master_project_path)
+if master_project:
+	graph = ProjectGraph(master_project)
+	graph.collect_dependencies(master_project)
+	success(f"Got {len(graph.values())} nodes of {basename(master_project_path)!r} dependencies")
+	unresolved_artifacts = graph.resolve_dependencies()
+	show_unresolved_dependencies(unresolved_artifacts)
+	pretty_debug(f"Currently order (excluding affected projects): {pretty_print_order(graph)}")
+	resolve_circular_references(graph)
+	success(f"Order: {pretty_print_order(graph)}")
+else:
+	failure("No such project.")