view tests/test-mq-qrefresh-interactive.t @ 23702:c48924787eaa

filectx.parents: enforce changeid of parent to be in own changectx ancestors

Because of the way filenodes are computed, you can have multiple changesets
"introducing" the same file revision. For example, in the changeset graph
below, changeset 2 and 3 both change a file -to- and -from- the same content.

  o 3: content = new
  |
  | o 2: content = new
  |/
  o 1: content = old

In such cases, the file revision is create once, when 2 is added, and just reused
for 3. So the file change in '3' (from "old" to "new)" has no linkrev pointing
to it).  We'll call this situation "linkrev-shadowing". As the linkrev is used for
optimization purposes when walking a file history, the linkrev-shadowing
results in an unexpected jump to another branch during such a walk.. This leads to
multiple bugs with log, annotate and rename detection.

One element to fix such bugs is to ensure that walking the file history sticks on
the same topology as the changeset's history. For this purpose, we extend the
logic in 'basefilectx.parents' so that it always defines the proper changeset
to associate the parent file revision with. This "proper" changeset has to be an
ancestor of the changeset associated with the child file revision.

This logic is performed in the '_adjustlinkrev' function. This function is
given the starting changeset and all the information regarding the parent file
revision. If the linkrev for the file revision is an ancestor of the starting
changeset, the linkrev is valid and will be used. If it is not, we detected a
topological jump caused by linkrev shadowing, we are going to walk the
ancestors of the starting changeset until we find one setting the file to the
revision we are trying to create.

The performance impact appears acceptable:

- We are walking the changelog once for each filelog traversal (as there should
  be no overlap between searches),

- changelog traversal itself is fairly cheap, compared to what is likely going
  to be perform on the result on the filelog traversal,

- We only touch the manifest for ancestors touching the file, And such
  changesets are likely to be the one introducing the file. (except in
  pathological cases involving merge),

- We use manifest diff instead of full manifest unpacking to check manifest
  content, so it does not involve applying multiple diffs in most case.

- linkrev shadowing is not the common case.

Tests for fixed issues in log, annotate and rename detection have been
added.

But this changeset does not solve all problems. It fixes -ancestry-
computation, but if the linkrev-shadowed changesets is the starting one, we'll
still get things wrong. We'll have to fix the bootstrapping of such operations
in a later changeset. Also, the usage of `hg log FILE`  without --follow still
has issues with linkrev pointing to hidden changesets, because it relies on the
`filelog` revset which implement its own traversal logic that is still to be
fixed.

Thanks goes to:
- Matt Mackall: for nudging me in the right direction
- Julien Cristau and Rémi Cardona: for keep telling me linkrev bug were an
  evolution show stopper for 3 years.
- Durham Goode: for finding a new linkrev issue every few weeks
- Mads Kiilerich: for that last rename bug who raise this topic over my
  anoyance limit.

Create configuration

  $ echo "[ui]" >> $HGRCPATH
  $ echo "interactive=true" >> $HGRCPATH

help qrefresh (no record)

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH
  $ hg help qrefresh
  hg qrefresh [-I] [-X] [-e] [-m TEXT] [-l FILE] [-s] [FILE]...
  
  update the current patch
  
      If any file patterns are provided, the refreshed patch will contain only
      the modifications that match those patterns; the remaining modifications
      will remain in the working directory.
  
      If -s/--short is specified, files currently included in the patch will be
      refreshed just like matched files and remain in the patch.
  
      If -e/--edit is specified, Mercurial will start your configured editor for
      you to enter a message. In case qrefresh fails, you will find a backup of
      your message in ".hg/last-message.txt".
  
      hg add/remove/copy/rename work as usual, though you might want to use git-
      style patches (-g/--git or [diff] git=1) to track copies and renames. See
      the diffs help topic for more information on the git diff format.
  
      Returns 0 on success.
  
  options ([+] can be repeated):
  
   -e --edit                invoke editor on commit messages
   -g --git                 use git extended diff format
   -s --short               refresh only files already in the patch and
                            specified files
   -U --currentuser         add/update author field in patch with current user
   -u --user USER           add/update author field in patch with given user
   -D --currentdate         add/update date field in patch with current date
   -d --date DATE           add/update date field in patch with given date
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
   -m --message TEXT        use text as commit message
   -l --logfile FILE        read commit message from file
  
  (some details hidden, use --verbose to show complete help)

help qrefresh (record)

  $ echo "record=" >> $HGRCPATH
  $ hg help qrefresh
  hg qrefresh [-I] [-X] [-e] [-m TEXT] [-l FILE] [-s] [FILE]...
  
  update the current patch
  
      If any file patterns are provided, the refreshed patch will contain only
      the modifications that match those patterns; the remaining modifications
      will remain in the working directory.
  
      If -s/--short is specified, files currently included in the patch will be
      refreshed just like matched files and remain in the patch.
  
      If -e/--edit is specified, Mercurial will start your configured editor for
      you to enter a message. In case qrefresh fails, you will find a backup of
      your message in ".hg/last-message.txt".
  
      hg add/remove/copy/rename work as usual, though you might want to use git-
      style patches (-g/--git or [diff] git=1) to track copies and renames. See
      the diffs help topic for more information on the git diff format.
  
      Returns 0 on success.
  
  options ([+] can be repeated):
  
   -e --edit                invoke editor on commit messages
   -g --git                 use git extended diff format
   -s --short               refresh only files already in the patch and
                            specified files
   -U --currentuser         add/update author field in patch with current user
   -u --user USER           add/update author field in patch with given user
   -D --currentdate         add/update date field in patch with current date
   -d --date DATE           add/update date field in patch with given date
   -I --include PATTERN [+] include names matching the given patterns
   -X --exclude PATTERN [+] exclude names matching the given patterns
   -m --message TEXT        use text as commit message
   -l --logfile FILE        read commit message from file
   -i --interactive         interactively select changes to refresh
  
  (some details hidden, use --verbose to show complete help)

  $ hg init a
  $ cd a

Base commit

  $ cat > 1.txt <<EOF
  > 1
  > 2
  > 3
  > 4
  > 5
  > EOF
  $ cat > 2.txt <<EOF
  > a
  > b
  > c
  > d
  > e
  > f
  > EOF

  $ mkdir dir
  $ cat > dir/a.txt <<EOF
  > hello world
  > 
  > someone
  > up
  > there
  > loves
  > me
  > EOF

  $ hg add 1.txt 2.txt dir/a.txt
  $ hg commit -m aaa
  $ hg qnew -d '0 0' patch

Changing files

  $ sed -e 's/2/2 2/;s/4/4 4/' 1.txt > 1.txt.new
  $ sed -e 's/b/b b/' 2.txt > 2.txt.new
  $ sed -e 's/hello world/hello world!/' dir/a.txt > dir/a.txt.new

  $ mv -f 1.txt.new 1.txt
  $ mv -f 2.txt.new 2.txt
  $ mv -f dir/a.txt.new dir/a.txt

Whole diff

  $ hg diff --nodates
  diff -r ed27675cb5df 1.txt
  --- a/1.txt
  +++ b/1.txt
  @@ -1,5 +1,5 @@
   1
  -2
  +2 2
   3
  -4
  +4 4
   5
  diff -r ed27675cb5df 2.txt
  --- a/2.txt
  +++ b/2.txt
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  diff -r ed27675cb5df dir/a.txt
  --- a/dir/a.txt
  +++ b/dir/a.txt
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up

partial qrefresh

  $ hg qrefresh -i -d '0 0' <<EOF
  > y
  > y
  > n
  > y
  > y
  > n
  > EOF
  diff --git a/1.txt b/1.txt
  2 hunks, 2 lines changed
  examine changes to '1.txt'? [Ynesfdaq?] y
  
  @@ -1,3 +1,3 @@
   1
  -2
  +2 2
   3
  record change 1/4 to '1.txt'? [Ynesfdaq?] y
  
  @@ -3,3 +3,3 @@
   3
  -4
  +4 4
   5
  record change 2/4 to '1.txt'? [Ynesfdaq?] n
  
  diff --git a/2.txt b/2.txt
  1 hunks, 1 lines changed
  examine changes to '2.txt'? [Ynesfdaq?] y
  
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  record change 3/4 to '2.txt'? [Ynesfdaq?] y
  
  diff --git a/dir/a.txt b/dir/a.txt
  1 hunks, 1 lines changed
  examine changes to 'dir/a.txt'? [Ynesfdaq?] n
  

After partial qrefresh 'tip'

  $ hg tip -p
  changeset:   1:0738af1a8211
  tag:         patch
  tag:         qbase
  tag:         qtip
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     [mq]: patch
  
  diff -r 1fd39ab63a33 -r 0738af1a8211 1.txt
  --- a/1.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/1.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   1
  -2
  +2 2
   3
   4
   5
  diff -r 1fd39ab63a33 -r 0738af1a8211 2.txt
  --- a/2.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/2.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  
After partial qrefresh 'diff'

  $ hg diff --nodates
  diff -r 0738af1a8211 1.txt
  --- a/1.txt
  +++ b/1.txt
  @@ -1,5 +1,5 @@
   1
   2 2
   3
  -4
  +4 4
   5
  diff -r 0738af1a8211 dir/a.txt
  --- a/dir/a.txt
  +++ b/dir/a.txt
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up

qrefresh interactively everything else

  $ hg qrefresh -i -d '0 0' <<EOF
  > y
  > y
  > y
  > y
  > EOF
  diff --git a/1.txt b/1.txt
  1 hunks, 1 lines changed
  examine changes to '1.txt'? [Ynesfdaq?] y
  
  @@ -1,5 +1,5 @@
   1
   2 2
   3
  -4
  +4 4
   5
  record change 1/2 to '1.txt'? [Ynesfdaq?] y
  
  diff --git a/dir/a.txt b/dir/a.txt
  1 hunks, 1 lines changed
  examine changes to 'dir/a.txt'? [Ynesfdaq?] y
  
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up
  record change 2/2 to 'dir/a.txt'? [Ynesfdaq?] y
  

After final qrefresh 'tip'

  $ hg tip -p
  changeset:   1:2c3f66afeed9
  tag:         patch
  tag:         qbase
  tag:         qtip
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     [mq]: patch
  
  diff -r 1fd39ab63a33 -r 2c3f66afeed9 1.txt
  --- a/1.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/1.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   1
  -2
  +2 2
   3
  -4
  +4 4
   5
  diff -r 1fd39ab63a33 -r 2c3f66afeed9 2.txt
  --- a/2.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/2.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,5 +1,5 @@
   a
  -b
  +b b
   c
   d
   e
  diff -r 1fd39ab63a33 -r 2c3f66afeed9 dir/a.txt
  --- a/dir/a.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/dir/a.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,4 +1,4 @@
  -hello world
  +hello world!
   
   someone
   up
  

After qrefresh 'diff'

  $ hg diff --nodates

  $ cd ..