tests/test-bisect2

findrenames: Optimise "addremove -s100" by matching files by their SHA1 hashes.

We speed up 'findrenames' for the usecase when a user specifies they
want a similarity of 100% by matching files by their exact SHA1 hash
value. This reduces the number of comparisons required to find exact
matches from O(n^2) to O(n).

While it would be nice if we could just use mercurial's pre-calculated
SHA1 hash for existing files, this hash includes the file's ancestor
information making it unsuitable for our purposes. Instead, we calculate
the hash of old content from scratch.

The following benchmarks were taken on the current head of crew:

addremove 100% similarity:
  rm -rf *; hg up -C; mv tests tests.new
  hg --time addremove -s100 --dry-run

  before:  real 176.350 secs (user 128.890+0.000 sys 47.430+0.000)
  after:   real   2.130 secs (user   1.890+0.000 sys  0.240+0.000)

addremove 75% similarity:
  rm -rf *; hg up -C; mv tests tests.new; \
      for i in tests.new/*; do echo x >> $i; done
  hg --time addremove -s75  --dry-run

  before: real 264.560 secs (user 215.130+0.000 sys 49.410+0.000)
  after:  real 218.710 secs (user 172.790+0.000 sys 45.870+0.000)

#!/bin/sh

# The tests in test-bisect are done on a linear history.
# Here the following repository history is used for testing:
#
#                     17
#                      |
#               18    16 
#                 \  /
#                  15
#                 /  \
#                /    \
#              10     13
#              / \     |
#             /   \    |  14
#        7   6     9  12 /
#         \ / \    |   |/
#          4   \   |  11
#           \   \  |  /
#            3   5 | /
#             \ /  |/ 
#              2   8
#               \ /
#                1
#                |
#                0

set -e

echo % init
hg init

echo % committing changes
echo > a
echo '0' >> a
hg add a
hg ci -m "0" -d "0 0"
echo '1' >> a
hg ci -m "1" -d "1 0"
echo '2' >> a
hg ci -m "2" -d "2 0"
echo '3' >> a
hg ci -m "3" -d "3 0"
echo '4' >> a
hg ci -m "4" -d "4 0"
# create branch
hg up -r 2
echo '5' >> b
hg add b
hg ci -m "5" -d "5 0"

# merge
hg merge
hg ci -m "merge 4,5" -d "6 0"

# create branch
hg up -r 4
echo '7' > c
hg add c
hg ci -m "7" -d "7 0"

# create branch
hg up -r 1
echo '8' > d
hg add d
hg ci -m "8" -d "8 0"
echo '9' >> d
hg ci -m "9" -d "9 0"

# merge
hg merge -r 6
hg ci -m "merge 6,9" -d "10 0"

# create branch
hg up -r 8
echo '11' > e
hg add e
hg ci -m "11" -d "11 0"
echo '12' >> e
hg ci -m "12" -d "12 0"
echo '13' >> e
hg ci -m "13" -d "13 0"

# create branch
hg up -r 11
echo '14' > f
hg add f
hg ci -m "14" -d "14 0"

# merge
hg up -r 13 -C
hg merge -r 10
hg ci -m "merge 10,13" -d "15 0"
echo '16' >> e
hg ci -m "16" -d "16 0"
echo '17' >> e
hg ci -m "17" -d "17 0"

# create branch
hg up -r 15
echo '18' >> e
hg ci -m "18" -d "18 0"


echo % log
hg log

echo % hg up -C
hg up -C

echo % complex bisect test 1  # first bad rev is 9
hg bisect -r
hg bisect -g 0
hg bisect -b 17   # -> update to rev 6
hg bisect -g      # -> update to rev 13
hg bisect -s      # -> update to rev 10
hg bisect -b      # -> update to rev 8
hg bisect -g      # -> update to rev 9
hg bisect -b

echo % complex bisect test 2  # first good rev is 13
hg bisect -r
hg bisect -g 18
hg bisect -b 1    # -> update to rev 6
hg bisect -s      # -> update to rev 10
hg bisect -b      # -> update to rev 12
hg bisect -b      # -> update to rev 13
hg bisect -g

echo % complex bisect test 3  
# first bad rev is 15 
# 10,9,13 are skipped an might be the first bad revisions as well
hg bisect -r
hg bisect -g 1
hg bisect -b 16   # -> update to rev 6
hg bisect -g      # -> update to rev 13
hg bisect -s      # -> update to rev 10
hg bisect -s      # -> update to rev 12
hg bisect -g      # -> update to rev 9
hg bisect -s      # -> update to rev 15
hg bisect -b

echo % complex bisect test 4
# first good revision is 17
# 15,16 are skipped an might be the first good revisions as well
hg bisect -r
hg bisect -g 17
hg bisect -b 8    # -> update to rev 10
hg bisect -b      # -> update to rev 13
hg bisect -b      # -> update to rev 15
hg bisect -s      # -> update to rev 16
hg bisect -s