status: prefer relative paths in Rust code
… when the repository root is under the current directory,
so the kernel needs to traverse fewer directory in every call
to `read_dir` or `symlink_metadata`.
Better yet would be to use libc functions like `openat` and `fstatat`
to remove such repeated traversals entirely, but the standard library
does not provide APIs based on those.
Maybe with a crate like https://crates.io/crates/openat instead?
Benchmarks of `rhg status` show that this patch is neutral in some configurations,
and makes the command up to ~20% faster in others.
Below is semi-arbitrary subset of results. The four numeric columns are:
time (in seconds) with this changeset’s parent, time with this changeset,
time difference (negative is better), time ratio (less than 1 is better).
```
mercurial-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.0061 -> 0.0059: -0.0002 (0.97)
mercurial-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0029 -> 0.0028: -0.0001 (0.97)
mozilla-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.2110 -> 0.2102: -0.0007 (1.00)
mozilla-dirstate-v2 | default-copies-clean.ignored.pbr | 0.0489 -> 0.0401: -0.0088 (0.82)
mozilla-dirstate-v2 | default-copies-clean.no-iu.pbr | 0.0479 -> 0.0393: -0.0085 (0.82)
mozilla-dirstate-v2 | default-copies-large.all.pbr | 0.1262 -> 0.1210: -0.0051 (0.96)
mozilla-dirstate-v2 | default-copies-small.ignored-unknown.pbr | 0.1262 -> 0.1200: -0.0062 (0.95)
mozilla-dirstate-v2 | default-copies-small.ignored.pbr | 0.0536 -> 0.0417: -0.0119 (0.78)
mozilla-dirstate-v2 | default-copies-small.no-iu.pbr | 0.0482 -> 0.0393: -0.0089 (0.81)
mozilla-dirstate-v2 | default-plain-clean.ignored.pbr | 0.0518 -> 0.0402: -0.0116 (0.78)
mozilla-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0481 -> 0.0392: -0.0088 (0.82)
mozilla-dirstate-v2 | default-plain-large.all.pbr | 0.1271 -> 0.1218: -0.0052 (0.96)
mozilla-dirstate-v2 | default-plain-small.ignored-unknown.pbr | 0.1225 -> 0.1202: -0.0022 (0.98)
mozilla-dirstate-v2 | default-plain-small.ignored.pbr | 0.0510 -> 0.0418: -0.0092 (0.82)
mozilla-dirstate-v2 | default-plain-small.no-iu.pbr | 0.0480 -> 0.0394: -0.0086 (0.82)
netbeans-dirstate-v1 | default-plain-clean.no-iu.pbr | 0.1442 -> 0.1422: -0.0020 (0.99)
netbeans-dirstate-v2 | default-plain-clean.no-iu.pbr | 0.0325 -> 0.0282: -0.0043 (0.87)
```
Differential Revision: https://phab.mercurial-scm.org/D12175
Test EOL patching
$ cat >> $HGRCPATH <<EOF
> [diff]
> git = 1
> EOF
Set up helpers
$ seteol () {
> if [ $1 = "LF" ]; then
> EOL='\n'
> else
> EOL='\r\n'
> fi
> }
$ makerepo () {
> seteol $1
> echo
> echo "# ==== setup $1 repository ===="
> echo '% hg init'
> hg init repo
> cd repo
> cat > .hgeol <<EOF
> [repository]
> native = $1
> [patterns]
> unix.txt = LF
> win.txt = CRLF
> **.txt = native
> EOF
> printf "first\r\nsecond\r\nthird\r\n" > win.txt
> printf "first\nsecond\nthird\n" > unix.txt
> printf "first${EOL}second${EOL}third${EOL}" > native.txt
> hg commit --addremove -m 'checkin'
> cd ..
> }
$ dotest () {
> seteol $1
> echo
> echo "% hg clone repo repo-$1"
> hg clone --noupdate repo repo-$1
> cd repo-$1
> cat > .hg/hgrc <<EOF
> [extensions]
> eol =
> [eol]
> native = $1
> EOF
> hg update
> echo '% native.txt'
> cat native.txt
> echo '% unix.txt'
> cat unix.txt
> echo '% win.txt'
> cat win.txt
> printf "first${EOL}third${EOL}" > native.txt
> printf "first\r\nthird\r\n" > win.txt
> printf "first\nthird\n" > unix.txt
> echo '% hg diff'
> hg diff > p
> cat p
> echo '% hg revert'
> hg revert --all
> echo '% hg import'
> hg import -m 'patch' p
> echo '% native.txt'
> cat native.txt
> echo '% unix.txt'
> cat unix.txt
> echo '% win.txt'
> cat win.txt
> echo '% hg diff -c tip'
> hg diff -c tip
> cd ..
> rm -r repo-$1
> }
Run tests
$ makerepo LF
# ==== setup LF repository ====
% hg init
adding .hgeol
adding native.txt
adding unix.txt
adding win.txt
$ dotest LF
% hg clone repo repo-LF
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
% native.txt
first
second
third
% unix.txt
first
second
third
% win.txt
first\r (esc)
second\r (esc)
third\r (esc)
% hg diff
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg revert
reverting native.txt
reverting unix.txt
reverting win.txt
% hg import
applying p
% native.txt
first
third
% unix.txt
first
third
% win.txt
first\r (esc)
third\r (esc)
% hg diff -c tip
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
$ dotest CRLF
% hg clone repo repo-CRLF
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
% native.txt
first\r (esc)
second\r (esc)
third\r (esc)
% unix.txt
first
second
third
% win.txt
first\r (esc)
second\r (esc)
third\r (esc)
% hg diff
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg revert
reverting native.txt
reverting unix.txt
reverting win.txt
% hg import
applying p
% native.txt
first\r (esc)
third\r (esc)
% unix.txt
first
third
% win.txt
first\r (esc)
third\r (esc)
% hg diff -c tip
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
$ rm -r repo
$ makerepo CRLF
# ==== setup CRLF repository ====
% hg init
adding .hgeol
adding native.txt
adding unix.txt
adding win.txt
$ dotest LF
% hg clone repo repo-LF
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
% native.txt
first
second
third
% unix.txt
first
second
third
% win.txt
first\r (esc)
second\r (esc)
third\r (esc)
% hg diff
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg revert
reverting native.txt
reverting unix.txt
reverting win.txt
% hg import
applying p
% native.txt
first
third
% unix.txt
first
third
% win.txt
first\r (esc)
third\r (esc)
% hg diff -c tip
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
$ dotest CRLF
% hg clone repo repo-CRLF
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
% native.txt
first\r (esc)
second\r (esc)
third\r (esc)
% unix.txt
first
second
third
% win.txt
first\r (esc)
second\r (esc)
third\r (esc)
% hg diff
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg revert
reverting native.txt
reverting unix.txt
reverting win.txt
% hg import
applying p
% native.txt
first\r (esc)
third\r (esc)
% unix.txt
first
third
% win.txt
first\r (esc)
third\r (esc)
% hg diff -c tip
diff --git a/native.txt b/native.txt
--- a/native.txt
+++ b/native.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
diff --git a/unix.txt b/unix.txt
--- a/unix.txt
+++ b/unix.txt
@@ -1,3 +1,2 @@
first
-second
third
diff --git a/win.txt b/win.txt
--- a/win.txt
+++ b/win.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
$ rm -r repo