context: introduce an `isintroducedafter` method and use it in copies
Right now, copy tracing make effort to not traverse the graph too much to save
performance. It uses a "limit" acting as a floor revision past which data are
no longer relevant to the current copy tracing.
However, to enforce this limit, it does a call to `filectx.rev()` and that
call can trigger a graph traversal on its own. That extra graph traversal is
unaware of the current limit and can become very expensive. That cost is
increased by the nature of work done in adjust link rev, we are not only
walking down the graph, we are also checking the affected file for each
revision we walk through. Something significantly more expensive than the walk
itself.
To work around this we need to make the `filectx` operation aware of the
current limit. The first step is to introduce a dedicated method:
`isintroducedafter`. We'll then rework that method logic to stop traversal as
soon as possible.
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 ..