view tests/test-linerange.py @ 30745:c1b7b2285522

revlog: flag processor

Add the ability for revlog objects to process revision flags and apply
registered transforms on read/write operations.

This patch introduces:
- the 'revlog._processflags()' method that looks at revision flags and applies
  flag processors registered on them. Due to the need to handle non-commutative
  operations, flag transforms are applied in stable order but the order in which
  the transforms are applied is reversed between read and write operations.
- the 'addflagprocessor()' method allowing to register processors on flags.
  Flag processors are defined as a 3-tuple of (read, write, raw) functions to be
  applied depending on the operation being performed.
- an update on 'revlog.addrevision()' behavior. The current flagprocessor design
  relies on extensions to wrap around 'addrevision()' to set flags on revision
  data, and on the flagprocessor to perform the actual transformation of its
  contents. In the lfs case, this means we need to process flags before we meet
  the 2GB size check, leading to performing some operations before it happens:
  - if flags are set on the revision data, we assume some extensions might be
    modifying the contents using the flag processor next, and we compute the
    node for the original revision data (still allowing extension to override
    the node by wrapping around 'addrevision()').
  - we then invoke the flag processor to apply registered transforms (in lfs's
    case, drastically reducing the size of large blobs).
  - finally, we proceed with the 2GB size check.

Note: In the case a cachedelta is passed to 'addrevision()' and we detect the
flag processor modified the revision data, we chose to trust the flag processor
and drop the cachedelta.

from __future__ import absolute_import

import unittest
from mercurial import error, mdiff

# for readability, line numbers are 0-origin
text1 = '''
           00 at OLD
           01 at OLD
           02 at OLD
02 at NEW, 03 at OLD
03 at NEW, 04 at OLD
04 at NEW, 05 at OLD
05 at NEW, 06 at OLD
           07 at OLD
           08 at OLD
           09 at OLD
           10 at OLD
           11 at OLD
'''[1:] # strip initial LF

text2 = '''
00 at NEW
01 at NEW
02 at NEW, 03 at OLD
03 at NEW, 04 at OLD
04 at NEW, 05 at OLD
05 at NEW, 06 at OLD
06 at NEW
07 at NEW
08 at NEW
09 at NEW
10 at NEW
11 at NEW
'''[1:] # strip initial LF

def filteredblocks(blocks, rangeb):
    """return `rangea` extracted from `blocks` coming from
    `mdiff.blocksinrange` along with the mask of blocks within rangeb.
    """
    filtered, rangea = mdiff.blocksinrange(blocks, rangeb)
    skipped = [b not in filtered for b in blocks]
    return rangea, skipped

class blocksinrangetests(unittest.TestCase):

    def setUp(self):
        self.blocks = list(mdiff.allblocks(text1, text2))
        assert self.blocks == [
            ([0, 3, 0, 2], '!'),
            ((3, 7, 2, 6), '='),
            ([7, 12, 6, 12], '!'),
            ((12, 12, 12, 12), '='),
        ], self.blocks

    def testWithinEqual(self):
        """linerange within an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #        ^^
        linerange2 = (3, 5)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (4, 6))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinEqualStrictly(self):
        """linerange matching exactly an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #       ^^^^
        linerange2 = (2, 6)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (3, 7))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinEqualLowerbound(self):
        """linerange at beginning of an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #       ^^
        linerange2 = (2, 4)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (3, 5))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinEqualLowerboundOneline(self):
        """oneline-linerange at beginning of an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #       ^
        linerange2 = (2, 3)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (3, 4))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinEqualUpperbound(self):
        """linerange at end of an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #        ^^^
        linerange2 = (3, 6)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (4, 7))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinEqualUpperboundOneLine(self):
        """oneline-linerange at end of an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #          ^
        linerange2 = (5, 6)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (6, 7))
        self.assertEqual(skipped, [True, False, True, True])

    def testWithinFirstBlockNeq(self):
        """linerange within the first "!" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #     ^
        #      |           (empty)
        #      ^
        #     ^^
        for linerange2 in [
            (0, 1),
            (1, 1),
            (1, 2),
            (0, 2),
        ]:
            linerange1, skipped = filteredblocks(self.blocks, linerange2)
            self.assertEqual(linerange1, (0, 3))
            self.assertEqual(skipped, [False, True, True, True])

    def testWithinLastBlockNeq(self):
        """linerange within the last "!" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #           ^
        #            ^
        #           |      (empty)
        #           ^^^^^^
        #                ^
        for linerange2 in [
            (6, 7),
            (7, 8),
            (7, 7),
            (6, 12),
            (11, 12),
        ]:
            linerange1, skipped = filteredblocks(self.blocks, linerange2)
            self.assertEqual(linerange1, (7, 12))
            self.assertEqual(skipped, [True, True, False, True])

    def testAccrossTwoBlocks(self):
        """linerange accross two blocks"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #      ^^^^
        linerange2 = (1, 5)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (0, 6))
        self.assertEqual(skipped, [False, False, True, True])

    def testCrossingSeveralBlocks(self):
        """linerange accross three blocks"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #      ^^^^^^^
        linerange2 = (1, 8)
        linerange1, skipped = filteredblocks(self.blocks, linerange2)
        self.assertEqual(linerange1, (0, 12))
        self.assertEqual(skipped, [False, False, False, True])

    def testStartInEqBlock(self):
        """linerange starting in an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #          ^^^^
        #         ^^^^^^^
        for linerange2, expectedlinerange1 in [
            ((5, 9), (6, 12)),
            ((4, 11), (5, 12)),
        ]:
            linerange1, skipped = filteredblocks(self.blocks, linerange2)
            self.assertEqual(linerange1, expectedlinerange1)
            self.assertEqual(skipped, [True, False, False, True])

    def testEndInEqBlock(self):
        """linerange ending in an "=" block"""
        # IDX 0         1
        #     012345678901
        # SRC NNOOOONNNNNN (New/Old)
        #      ^^
        #     ^^^^^
        for linerange2, expectedlinerange1 in [
            ((1, 3), (0, 4)),
            ((0, 4), (0, 5)),
        ]:
            linerange1, skipped = filteredblocks(self.blocks, linerange2)
            self.assertEqual(linerange1, expectedlinerange1)
            self.assertEqual(skipped, [False, False, True, True])

    def testOutOfRange(self):
        """linerange exceeding file size"""
        exctype = error.Abort
        for linerange2 in [
            (0, 34),
            (15, 12),
        ]:
            # Could be `with self.assertRaises(error.Abort)` but python2.6
            # does not have assertRaises context manager.
            try:
                mdiff.blocksinrange(self.blocks, linerange2)
            except exctype as exc:
                self.assertTrue('line range exceeds file size' in str(exc))
            else:
                self.fail('%s not raised' % exctype.__name__)

if __name__ == '__main__':
    import silenttestrunner
    silenttestrunner.main(__name__)