requires: re-use vfs.tryread for simplicity
Avoids calling `set` twice or having to re-raise an exception and implements the routine with a single return expression.
Testing diff --change, --from, --to
$ 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
Test --from and --to
$ hg diff --from . --rev .
abort: cannot specify both --from and --rev
[10]
$ hg diff --to . --rev .
abort: cannot specify both --to and --rev
[10]
$ hg diff --from . --change .
abort: cannot specify both --from and --change
[10]
$ hg diff --to . --change .
abort: cannot specify both --to and --change
[10]
$ echo dirty > file.txt
$ hg diff --from .
diff -r bf5ff72eb7e0 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 @@
-third
+dirty
$ hg diff --from . --reverse
diff -r bf5ff72eb7e0 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 @@
-dirty
+third
$ hg diff --to .
diff -r bf5ff72eb7e0 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 @@
-dirty
+third
$ hg diff --from 0 --to 2
diff -r 4bb65dda5db4 -r bf5ff72eb7e0 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
+third
$ hg diff --from 2 --to 0
diff -r bf5ff72eb7e0 -r 4bb65dda5db4 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 @@
-third
+first
$ hg co -C .
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ 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
[10]
$ 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
merge diff should show only manual edits to a merge:
$ hg diff --config diff.merge=yes -c 6
(no diff output is expected here)
Construct an "evil merge" that does something other than just the merge.
$ hg co ".^"
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)
$ echo 11 >> file.txt
$ hg ci -m 'merge 8 to y with manual edit of 11' # 7
created new head
$ hg diff -c 7
diff -r 273b50f17c6d -r 8ad85e839ba7 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 +6,7 @@
5
6
7
-8
+y
9
10
+11
Contrast with the `hg diff -c 7` version above: only the manual edit shows
up, making it easy to identify changes someone is otherwise trying to sneak
into a merge.
$ hg diff --config diff.merge=yes -c 7
diff -r 8ad85e839ba7 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -9,3 +9,4 @@
y
9
10
+11
Set up a conflict.
$ hg co ".^"
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ sed -e 's,^8$,z,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg ci -m 'conflicting edit: 8 to z'
created new head
$ echo "this file is new in p1 of the merge" > new-file-p1.txt
$ hg ci -Am 'new file' new-file-p1.txt
$ hg log -r . --template 'p1 will be rev {rev}\n'
p1 will be rev 9
$ hg co 5
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo "this file is new in p2 of the merge" > new-file-p2.txt
$ hg ci -Am 'new file' new-file-p2.txt
created new head
$ hg log -r . --template 'p2 will be rev {rev}\n'
p2 will be rev 10
$ hg co -- 9
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg merge -r 10
merging file.txt
warning: conflicts while merging file.txt! (edit, then use 'hg resolve --mark')
1 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
[1]
$ hg revert file.txt -r .
$ hg resolve -ma
(no more unresolved files)
$ hg commit -m 'merge conflicted edit'
Without diff.merge, it's a diff against p1
$ hg diff --config diff.merge=no -c 11
diff -r fd1f17c90d7c -r 5010caab09f6 new-file-p2.txt
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/new-file-p2.txt Thu Jan 01 00:00:00 1970 +0000
@@ -0,0 +1,1 @@
+this file is new in p2 of the merge
With diff.merge, it's a diff against the conflicted content.
$ hg diff --config diff.merge=yes -c 11
diff -r 5010caab09f6 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,12 +6,6 @@
5
6
7
-<<<<<<< local: fd1f17c90d7c - test: new file
z
-||||||| base: ae119d680c82 - test: lots of text
-8
-=======
-y
->>>>>>> other: d9e7de69eac3 - test: new file
9
10
There must _NOT_ be a .hg/merge directory leftover.
$ test ! -d .hg/merge
(No output is expected)
$ cd ..