Add recipes to the depgraph command.

recipe_engine/depgraph.py

Index: recipe_engine/depgraph.py
diff --git a/recipe_engine/depgraph.py b/recipe_engine/depgraph.py
index e12ac38c37b5353bf2d227c8c2a1dd43e47d47f8..dab070e957b7d093787cf5aa0223fca32235a9c4 100644
--- a/recipe_engine/depgraph.py
+++ b/recipe_engine/depgraph.py
@@ -6,6 +6,7 @@ from __future__ import print_function
 
 import sys
 import os
+import collections
 
 from . import loader
 
@@ -20,29 +21,98 @@ _GRAPH_FOOTER = """}
 """
 
 
-def main(universe, ignore_packages, stdout):
-  packages = {}
+def main(universe, own_package, ignore_packages, stdout, recipe_filter):
   module_to_package = {}
-  edges = []
+
+  # All deps maps a tuple of (is_recipe, id) to deps (list of ids). is_recipe is
+  # a boolean, all ids are strings.
+  all_deps = {}
   for package, module_name in universe.loop_over_recipe_modules():
+    if package in ignore_packages:
+      continue
     mod = universe.load(package, module_name)
 
-    for dep in mod.LOADED_DEPS:
-      edges.append((mod.NAME, dep))
-    packages.setdefault(package.name, []).append(mod.NAME)
+    all_deps[(False, mod.NAME)] = mod.LOADED_DEPS
     module_to_package[mod.NAME] = package.name
 
+  if recipe_filter:
+    recipe_to_package = {}
+    universe_view = loader.UniverseView(universe, own_package)
+    for _, recipe_name in universe_view.loop_over_recipes():
+      if recipe_filter not in recipe_name:
+        continue
+
+      recipe = universe_view.load_recipe(recipe_name)
+
+      all_deps[(True, recipe_name)] = recipe.LOADED_DEPS
+      recipe_to_package[recipe_name] = own_package
+
+    # If we actually found any recipes
+    if recipe_to_package:
+      # Prune anything our recipe doesn't see via BFS.
+      queue = [
+          (True, name) for (is_recipe, name), _ in all_deps.items()
+            if is_recipe]
+
+      to_keep = set()
+      while queue:
+        itm = queue.pop()
+        to_keep.add(itm)
+        for dep in all_deps[itm]:
+          queue.append((False, dep))
+
+      all_deps = {key: deps for key, deps in all_deps.items() if key in to_keep}
+
+      mod_names = [
+          name for (is_recipe, name), _ in all_deps.items() if not is_recipe]
+      module_to_package = {
+          m_name: p_name for m_name, p_name in module_to_package.items()
+          if m_name in mod_names}
+
+      recipe_names = [
+          name for (is_recipe, name), _ in all_deps.items() if is_recipe]
+      recipe_to_package = {
+          r_name: p_name for r_name, p_name in recipe_to_package.items()
+          if r_name in recipe_names}
+
+
   print(_GRAPH_HEADER, file=stdout)
+  edges = []
+  for (is_recipe, name), deps in all_deps.items():
+    for dep in deps:
+      edges.append(((is_recipe, name), dep))
+
   for edge in edges:
-    if (module_to_package[edge[0]] in ignore_packages or
-        module_to_package[edge[1]] in ignore_packages):
+    (is_recipe, first_name), second_name = edge
+
+    if not is_recipe:
+      if module_to_package[first_name] in ignore_packages:
+        continue
+    else:
+      if recipe_to_package[first_name] in ignore_packages:
+        continue
+      first_name = 'recipe ' + first_name
+
+    if module_to_package[second_name] in ignore_packages:
       continue
-    print('  %s -> %s' % (edge[0], edge[1]), file=stdout)
+
+    print('  "%s" -> "%s"' % (first_name, second_name), file=stdout)
+
+  packages = {}
+  for module, package in module_to_package.iteritems():
+    packages.setdefault(package, []).append(module)
   for package, modules in packages.iteritems():
     if package in ignore_packages:
       continue
     # The "cluster_" prefix has magic meaning for graphviz and makes it
     # draw a box around the subgraph.
     print('  subgraph "cluster_%s" { label="%s"; %s; }' % (
-              package, package, '; '.join(modules)), file=stdout)
+        package, package, '; '.join(modules)), file=stdout)
+
+  if recipe_filter and recipe_to_package:
+    recipe_names = [
+        '"recipe %s"' % name for name in recipe_to_package.keys()]
+    print('  subgraph "cluster_recipes" { label="recipes"; %s; }' % (
+        '; '.join(recipe_names)), file=stdout)
+
   print(_GRAPH_FOOTER, file=stdout)