Function p4ChangesForPaths

git-p4.py:1284–1360

(depotPaths, changeRange, requestedBlockSize)

def p4ChangesForPaths(depotPaths, changeRange, requestedBlockSize):
    assert depotPaths

    # Parse the change range into start and end. Try to find integer
    # revision ranges as these can be broken up into blocks to avoid
    # hitting server-side limits (maxrows, maxscanresults). But if
    # that doesn't work, fall back to using the raw revision specifier
    # strings, without using block mode.

    if changeRange is None or changeRange == '':
        changeStart = 1
        changeEnd = p4_last_change()
        block_size = chooseBlockSize(requestedBlockSize)
    else:
        parts = changeRange.split(',')
        assert len(parts) == 2
        try:
            changeStart, changeEnd = p4ParseNumericChangeRange(parts)
            block_size = chooseBlockSize(requestedBlockSize)
        except ValueError:
            changeStart = parts[0][1:]
            changeEnd = parts[1]
            if requestedBlockSize:
                die("cannot use --changes-block-size with non-numeric revisions")
            block_size = None

    changes = set()

    # Retrieve changes a block at a time, to prevent running
    # into a MaxResults/MaxScanRows error from the server. If
    # we _do_ hit one of those errors, turn down the block size

    while True:
        cmd = ['changes']

        if block_size:
            end = min(changeEnd, changeStart + block_size)
            revisionRange = "%d,%d" % (changeStart, end)
        else:
            revisionRange = "%s,%s" % (changeStart, changeEnd)

        for p in depotPaths:
            cmd += ["%s...@%s" % (p, revisionRange)]

        # fetch the changes
        try:
            result = p4CmdList(cmd, errors_as_exceptions=True)
        except P4RequestSizeException as e:
            if not block_size:
                block_size = e.limit
            elif block_size > e.limit:
                block_size = e.limit
            else:
                block_size = max(2, block_size // 2)

            if verbose:
                print("block size error, retrying with block size {0}".format(block_size))
            continue