"{ Package: 'stx:goodies/monticello' }"

Object subclass:#MCFrontier

	instanceVariableNames:'frontier bag'

	classVariableNames:''

	poolDictionaries:''

	category:'SCM-Monticello-Versioning'

!

!MCFrontier class methodsFor:'instance creation'!

frontierOn: aVersionInfo

	^ self frontierOnAll: (Array with: aVersionInfo)

!

frontierOn: aVersionInfo and: otherVersionInfo

	^ self frontierOnAll: (Array with: aVersionInfo with: otherVersionInfo)

!

frontierOnAll: aCollection

	| remaining  allVersions |

	remaining := Bag new.

	allVersions _ (aCollection gather: [:ea | ea withBreadthFirstAncestors]) asSet.

	allVersions do: [:ea | remaining addAll: ea ancestors].

	^self new frontier: aCollection bag: remaining

! !

!MCFrontier methodsFor:'accessing'!

frontier

	^frontier

! !

!MCFrontier methodsFor:'advancing'!

remove: aVersionInfo

	frontier remove: aVersionInfo.

	aVersionInfo ancestors  do:

		[ :ancestor |

			bag remove: ancestor.

			(bag occurrencesOf: ancestor) = 0

				ifTrue: [frontier add: ancestor]].

	^aVersionInfo

!

removeAll: collection

	collection do: [ :n | self remove: n]

! !

!MCFrontier methodsFor:'initialization'!

frontier: f bag: remaining

	frontier := f asOrderedCollection.

	bag := remaining

! !

!MCFrontier class methodsFor:'documentation'!

version

    ^ '$Header: /cvs/stx/stx/goodies/monticello/MCFrontier.st,v 1.2 2012-09-11 21:22:09 cg Exp $'

! !