revlog: group delta computation methods under _deltacomputer object Extracting these methods from revlog will allow changing the implementation of the deltacomputer, by providing this interface: __init__(self, revlog) - constructor that initialize the object from a given revlog buildtext(self, revinfo, fh) - builds the fulltext version of a revision from a _revisioninfo object and the file handle to the .d (or .i for inline mode) file. finddeltainfo(self, revinfo, fh) - find a revision in the revlog against which it is acceptable to build a delta, and build the corresponding _deltainfo. It should now be easier to write an experimental feature that would replace _deltacomputer by another object, for example one that would know how to parallelize the delta computation in order to quicken the storage of multiple revisions.