tests/test-strict.out

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)

adding a
0: a
hg: unknown command 'an'
Mercurial Distributed SCM

basic commands:

 add        add the specified files on the next commit
 annotate   show changeset information by line for each file
 clone      make a copy of an existing repository
 commit     commit the specified files or all outstanding changes
 diff       diff repository (or selected files)
 export     dump the header and diffs for one or more changesets
 forget     forget the specified files on the next commit
 init       create a new repository in the given directory
 log        show revision history of entire repository or files
 merge      merge working directory with another revision
 pull       pull changes from the specified source
 push       push changes to the specified destination
 remove     remove the specified files on the next commit
 serve      start stand-alone webserver
 status     show changed files in the working directory
 summary    summarize working directory state
 update     update working directory (or switch revisions)

use "hg help" for the full list of commands or "hg -v" for details
0: a
% should succeed - up is an alias, not an abbreviation
0 files updated, 0 files merged, 0 files removed, 0 files unresolved