copies: do full filtering at end of _changesetforwardcopies()
As mentioned earlier, pathcopies() is very slow when copies are stored
in the changeset. Most of the cost comes from calling _chain() for
every changeset, which is slow because it needs to read manifests. It
needs to read manifests to be able to filter out copies that are were
created in one commit and then deleted. (It also filters out copies
that were created from a file that didn't exist in the starting
revision, but that's a fixed revision across calls to _chain(), so
it's much cheaper.)
This patch changes from _chainandfilter() to just _chain() in the main
loop in _changesetforwardcopies(). It instead removes copies that have
subsequently been removed by using ctx.filesremoved(). We thus rely on
that to be fast.
It timed this command in mozilla-unified:
hg debugpathcopies FIREFOX_59_0b3_BUILD2 FIREFOX_BETA_59_END
It took 18s before and 1.1s after. It's still faster when copy
information is stored in filelogs: 0.70s. It also still gets slow when
there are merge commits involved, because we read manifests there
too. We'll deal with that later.
Differential Revision: https://phab.mercurial-scm.org/D6419
Testing diff --change
$ hg init a
$ cd a
$ echo "first" > file.txt
$ hg add file.txt
$ hg commit -m 'first commit' # 0
$ echo "second" > file.txt
$ hg commit -m 'second commit' # 1
$ echo "third" > file.txt
$ hg commit -m 'third commit' # 2
$ hg diff --nodates --change 1
diff -r 4bb65dda5db4 -r e9b286083166 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-first
+second
$ hg diff --change e9b286083166
diff -r 4bb65dda5db4 -r e9b286083166 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-first
+second
$ cd ..
Test dumb revspecs: top-level "x:y", "x:", ":y" and ":" ranges should be handled
as pairs even if x == y, but not for "f(x:y)" nor "x::y" (issue3474, issue4774)
$ hg clone -q a dumbspec
$ cd dumbspec
$ echo "wdir" > file.txt
$ hg diff -r 2:2
$ hg diff -r 2:.
$ hg diff -r 2:
$ hg diff -r :0
$ hg diff -r '2:first(2:2)'
$ hg diff -r 'first(2:2)' --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r '(2:2)' --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r 2::2 --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r "2 and 1"
abort: empty revision range
[255]
$ cd ..
$ hg clone -qr0 a dumbspec-rev0
$ cd dumbspec-rev0
$ echo "wdir" > file.txt
$ hg diff -r :
$ hg diff -r 'first(:)' --nodates
diff -r 4bb65dda5db4 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-first
+wdir
$ cd ..
Testing diff --change when merge:
$ cd a
$ for i in 1 2 3 4 5 6 7 8 9 10; do
> echo $i >> file.txt
> done
$ hg commit -m "lots of text" # 3
$ sed -e 's,^2$,x,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg commit -m "change 2 to x" # 4
$ hg up -r 3
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ sed -e 's,^8$,y,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg commit -m "change 8 to y"
created new head
$ hg up -C -r 4
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge -r 5
merging file.txt
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "merge 8 to y" # 6
$ hg diff --change 5
diff -r ae119d680c82 -r 9085c5c02e52 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,6 +6,6 @@
5
6
7
-8
+y
9
10
must be similar to 'hg diff --change 5':
$ hg diff -c 6
diff -r 273b50f17c6d -r 979ca961fd2e file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,6 +6,6 @@
5
6
7
-8
+y
9
10
$ cd ..