revsetlang: build optimized tree by helper function
This should make optimize() more readable, but it doubles the parsing cost.
(original)
$ python -m timeit -n10000 -s 'from mercurial import revsetlang as L' \
'L.optimize(L.analyze(L.parse("::tip")))'
10000 loops, best of 3: 18.1 usec per loop
(this patch)
$ python -m timeit -n10000 -s 'from mercurial import revsetlang as L' \
'L._treecache.clear(); L.optimize(L.analyze(L.parse("::tip")))'
10000 loops, best of 3: 48.4 usec per loop
30usec isn't dominant compared to the revset evaluation, but that is a cost.
That's why a parsed tree is cached, which can benefit in hgweb or chg server.
$ hg init
$ cat > a <<EOF
> a
> b
> c
> EOF
$ hg ci -Am adda
adding a
$ cat > a <<EOF
> d
> e
> f
> EOF
$ hg ci -m moda
$ hg diff --reverse -r0 -r1
diff -r 2855cdcfcbb7 -r 8e1805a3cf6e a
--- a/a Thu Jan 01 00:00:00 1970 +0000
+++ b/a Thu Jan 01 00:00:00 1970 +0000
@@ -1,3 +1,3 @@
-d
-e
-f
+a
+b
+c
$ cat >> a <<EOF
> g
> h
> EOF
$ hg diff --reverse --nodates
diff -r 2855cdcfcbb7 a
--- a/a
+++ b/a
@@ -1,5 +1,3 @@
d
e
f
-g
-h
should show removed file 'a' as being added
$ hg revert a
$ hg rm a
$ hg diff --reverse --nodates a
diff -r 2855cdcfcbb7 a
--- /dev/null
+++ b/a
@@ -0,0 +1,3 @@
+d
+e
+f
should show added file 'b' as being removed
$ echo b >> b
$ hg add b
$ hg diff --reverse --nodates b
diff -r 2855cdcfcbb7 b
--- a/b
+++ /dev/null
@@ -1,1 +0,0 @@
-b