Move the backtracking code from action_build() to a new backtrack_depgraph()

function.

svn path=/main/trunk/; revision=13818

2 files changed, 46 insertions, 38 deletions

diff --git a/pym/_emerge/actions.py b/pym/_emerge/actions.py
index 4883e3730..f7ec0a15b 100644
--- a/pym/_emerge/actions.py
+++ b/pym/_emerge/actions.py
@@ -40,7 +40,7 @@ from _emerge.clear_caches import clear_caches
 from _emerge.countdown import countdown
 from _emerge.create_depgraph_params import create_depgraph_params
 from _emerge.Dependency import Dependency
-from _emerge.depgraph import depgraph, resume_depgraph, _frozen_depgraph_config
+from _emerge.depgraph import backtrack_depgraph, depgraph, resume_depgraph
 from _emerge.DepPrioritySatisfiedRange import DepPrioritySatisfiedRange
 from _emerge.emergelog import emergelog
 from _emerge.is_valid_package_atom import is_valid_package_atom
@@ -301,48 +301,24 @@ def action_build(settings, trees, mtimedb,
 			print "Calculating dependencies  ",
 			sys.stdout.flush()
 
-		runtime_pkg_mask = None
-		allow_backtracking = True
-		backtracked = False
-		frozen_config = _frozen_depgraph_config(settings, trees,
-			myopts, spinner)
 		myparams = create_depgraph_params(myopts, myaction)
-		while True:
-			mydepgraph = depgraph(settings, trees, myopts, myparams, spinner,
-				frozen_config=frozen_config,
-				allow_backtracking=allow_backtracking,
-				runtime_pkg_mask=runtime_pkg_mask)
-			try:
-				retval, favorites = mydepgraph.select_files(myfiles)
-			except portage.exception.PackageNotFound, e:
-				portage.writemsg("\n!!! %s\n" % str(e), noiselevel=-1)
-				return 1
-			except portage.exception.PackageSetNotFound, e:
-				root_config = trees[settings["ROOT"]]["root_config"]
-				display_missing_pkg_set(root_config, e.value)
-				return 1
-			if not retval:
-				if mydepgraph.need_restart():
-					runtime_pkg_mask = mydepgraph.get_runtime_pkg_mask()
-					backtracked = True
-				elif backtracked and allow_backtracking:
-					# Backtracking failed, so disable it and do
-					# a plain dep calculation + error message.
-					allow_backtracking = False
-					runtime_pkg_mask = None
-				else:
-					if show_spinner:
-						print "\b\b... done!"
-					mydepgraph.display_problems()
-					return 1
-			else:
-				break
-
-		del frozen_config, runtime_pkg_mask
+		try:
+			success, mydepgraph, favorites = backtrack_depgraph(
+				settings, trees, myopts, myparams, myaction, myfiles, spinner)
+		except portage.exception.PackageSetNotFound, e:
+			if show_spinner:
+				print "\b\b... done!"
+			root_config = trees[settings["ROOT"]]["root_config"]
+			display_missing_pkg_set(root_config, e.value)
+			return 1
 
 		if show_spinner:
 			print "\b\b... done!"
 
+		if not success:
+			mydepgraph.display_problems()
+			return 1
+
 	if "--pretend" not in myopts and \
 		("--ask" in myopts or "--tree" in myopts or \
 		"--verbose" in myopts) and \
diff --git a/pym/_emerge/depgraph.py b/pym/_emerge/depgraph.py
index 11b4b4963..8297a360e 100644
--- a/pym/_emerge/depgraph.py
+++ b/pym/_emerge/depgraph.py
@@ -30,6 +30,7 @@ from _emerge.BlockerCache import BlockerCache
 from _emerge.BlockerDepPriority import BlockerDepPriority
 from _emerge.changelog import calc_changelog
 from _emerge.countdown import countdown
+from _emerge.create_depgraph_params import create_depgraph_params
 from _emerge.create_world_atom import create_world_atom
 from _emerge.Dependency import Dependency
 from _emerge.DependencyArg import DependencyArg
@@ -4887,6 +4888,37 @@ def insert_category_into_atom(atom, category):
 		ret = None
 	return ret
 
+def backtrack_depgraph(settings, trees, myopts, myparams, 
+	myaction, myfiles, spinner):
+	"""
+	Raises PackageSetNotFound if myfiles contains a missing package set.
+	"""
+	runtime_pkg_mask = None
+	allow_backtracking = True
+	backtracked = False
+	frozen_config = _frozen_depgraph_config(settings, trees,
+		myopts, spinner)
+	while True:
+		mydepgraph = depgraph(settings, trees, myopts, myparams, spinner,
+			frozen_config=frozen_config,
+			allow_backtracking=allow_backtracking,
+			runtime_pkg_mask=runtime_pkg_mask)
+		success, favorites = mydepgraph.select_files(myfiles)
+		if not success:
+			if mydepgraph.need_restart():
+				runtime_pkg_mask = mydepgraph.get_runtime_pkg_mask()
+				backtracked = True
+			elif backtracked and allow_backtracking:
+				# Backtracking failed, so disable it and do
+				# a plain dep calculation + error message.
+				allow_backtracking = False
+				runtime_pkg_mask = None
+			else:
+				break
+		else:
+			break
+	return (success, mydepgraph, favorites)
+
 def resume_depgraph(settings, trees, mtimedb, myopts, myparams, spinner):
 	"""
 	Construct a depgraph for the given resume list. This will raise