tests/test-mq-git.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)

% git=auto: regular patch creation
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
# Date 0 0

diff -r 000000000000 -r ef8dafc9fa4c a
--- /dev/null
+++ b/a
@@ -0,0 +1,1 @@
+a
% git=auto: git patch creation with copy
# HG changeset patch
# Parent ef8dafc9fa4caff80f6e243eb0171bcd60c455b4
# Date 0 0

diff --git a/a b/b
copy from a
copy to b
% git=auto: git patch when using --git
# HG changeset patch
# Parent 99586d5f048c399e20f81cee41fbb3809c0e735d
# Date 0 0

diff --git a/regular b/regular
new file mode 100644
--- /dev/null
+++ b/regular
@@ -0,0 +1,1 @@
+regular
% git=auto: regular patch after qrefresh without --git
# HG changeset patch
# Parent 99586d5f048c399e20f81cee41fbb3809c0e735d
# Date 0 0

diff -r 99586d5f048c regular
--- /dev/null
+++ b/regular
@@ -0,0 +1,1 @@
+regular
% git=keep: git patch with --git
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
# Date 0 0

diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,1 @@
+a
% git=keep: git patch after qrefresh without --git
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
# Date 0 0

diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,2 @@
+a
+a
% git=yes: git patch
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
# Date 0 0

diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,1 @@
+a
% git=yes: git patch after qrefresh
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
# Date 0 0

diff --git a/a b/a
new file mode 100644
--- /dev/null
+++ b/a
@@ -0,0 +1,2 @@
+a
+a
% git=no: regular patch with copy
# HG changeset patch
# Parent ef8dafc9fa4caff80f6e243eb0171bcd60c455b4
# Date 0 0

diff -r ef8dafc9fa4c -r a70404f79ba3 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+a
% git=no: regular patch after qrefresh with copy
# HG changeset patch
# Parent ef8dafc9fa4caff80f6e243eb0171bcd60c455b4
# Date 0 0

diff -r ef8dafc9fa4c b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+a
diff -r ef8dafc9fa4c c
--- /dev/null
+++ b/c
@@ -0,0 +1,1 @@
+a