mercurial/graphmod.py
author Dirkjan Ochtman <dirkjan@ochtman.nl>
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# Revision graph generator for Mercurial
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#
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# Copyright 2008 Dirkjan Ochtman <dirkjan@ochtman.nl>
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# Copyright 2007 Joel Rosdahl <joel@rosdahl.net>
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#
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# This software may be used and distributed according to the terms of the
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# GNU General Public License version 2, incorporated herein by reference.
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"""supports walking the history as DAGs suitable for graphical output
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The most basic format we use is that of::
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  (id, type, data, [parentids])
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The node and parent ids are arbitrary integers which identify a node in the
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context of the graph returned. Type is a constant specifying the node type.
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Data depends on type.
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"""
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from mercurial.node import nullrev
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CHANGESET = 'C'
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def revisions(repo, start, stop):
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    """cset DAG generator yielding (id, CHANGESET, ctx, [parentids]) tuples
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    This generator function walks through the revision history from revision
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    start to revision stop (which must be less than or equal to start). It
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    returns a tuple for each node. The node and parent ids are arbitrary
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    integers which identify a node in the context of the graph returned.
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    """
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    cur = start
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    while cur >= stop:
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        ctx = repo[cur]
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        parents = [p.rev() for p in ctx.parents() if p.rev() != nullrev]
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        yield (cur, CHANGESET, ctx, sorted(parents))
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        cur -= 1
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def filerevs(repo, path, start, stop):
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    """file cset DAG generator yielding (id, CHANGESET, ctx, [parentids]) tuples
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    This generator function walks through the revision history of a single
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    file from revision start down to revision stop.
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    """
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    filerev = len(repo.file(path)) - 1
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    while filerev >= 0:
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        fctx = repo.filectx(path, fileid=filerev)
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        parents = [f.linkrev() for f in fctx.parents() if f.path() == path]
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        rev = fctx.rev()
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        if rev <= start:
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            yield (rev, CHANGESET, fctx, sorted(parents))
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        if rev <= stop:
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            break
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        filerev -= 1
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def nodes(repo, nodes):
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    """cset DAG generator yielding (id, CHANGESET, ctx, [parentids]) tuples
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    This generator function walks the given nodes. It only returns parents
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    that are in nodes, too.
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    """
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    include = set(nodes)
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    for node in nodes:
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        ctx = repo[node]
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        parents = [p.rev() for p in ctx.parents() if p.node() in include]
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        yield (ctx.rev(), CHANGESET, ctx, sorted(parents))
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def colored(dag):
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    """annotates a DAG with colored edge information
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    For each DAG node this function emits tuples::
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      (id, type, data, (col, color), [(col, nextcol, color)])
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    with the following new elements:
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      - Tuple (col, color) with column and color index for the current node
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      - A list of tuples indicating the edges between the current node and its
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        parents.
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    """
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    seen = []
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    colors = {}
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    newcolor = 1
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    for (cur, type, data, parents) in dag:
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        # Compute seen and next
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        if cur not in seen:
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            seen.append(cur) # new head
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            colors[cur] = newcolor
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            newcolor += 1
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        col = seen.index(cur)
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        color = colors.pop(cur)
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        next = seen[:]
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        # Add parents to next
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        addparents = [p for p in parents if p not in next]
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        next[col:col + 1] = addparents
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        # Set colors for the parents
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        for i, p in enumerate(addparents):
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            if not i:
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                colors[p] = color
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            else:
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                colors[p] = newcolor
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                newcolor += 1
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        # Add edges to the graph
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        edges = []
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        for ecol, eid in enumerate(seen):
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            if eid in next:
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                edges.append((ecol, next.index(eid), colors[eid]))
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            elif eid == cur:
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                for p in parents:
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                    edges.append((ecol, next.index(p), colors[p]))
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        # Yield and move on
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        yield (cur, type, data, (col, color), edges)
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        seen = next