view contrib/editmerge @ 42565:4764e8436b2a

filemerge: make last line of prompts <40 english chars (issue6158)

I've chosen <40 as the target so that other languages that may have a 2x blowup
in character count can still have a chance to fit into an 80 column screen.

Previously, we would show a prompt like:

```
keep (l)ocal [dest], take (o)ther [source], or leave (u)nresolved for some/potentially/really/long/path?
```

On at least some systems, if readline was in use then the last line of the
prompt would be wrapped strangely if it couldn't fit entirely on one line. This
strange wrapping may be just a carriage return without a line feed, overwriting
the beginning of the line; example (100 columns wide, 65 character filename, and
yes there's 10 spaces on the end, I assume this is to handle the user inputting
longest word we provide as an option, "unresolved"):

```
ng/dir/name/that/does/not/work/well/with/readline/file.txt? ave (u)nresolved for some/lon
```

In some cases it may partially wrap onto the next line, but still be missing
earlier parts in the line, such as below (60 columns wide, 65 character
filename):

```
 rev], or leave (u)nresolved for some/long/dir/name/that/do
s/not/work/well/with/readline/file.txt?
```

With this fix, this looks like this on a 60 column screen:

```
tool vim_with_markers (for pattern some/long/dir/name/that/d
oes/not/work/well/with/readline/file.txt) can't handle binar
y
tool meld can't handle binary
tool vim_with_markers can't handle binary
tool internal:merge3 can't handle binary
tool merge can't handle binary
no tool found to merge some/long/dir/name/that/does/not/work
/well/with/readline/file.txt
file 'some/long/dir/name/that/does/not/work/well/with/readli
ne/file.txt' needs to be resolved.
You can keep (l)ocal [working copy], take (o)ther [merge rev
], or leave (u)nresolved.
What do you want to do?
```

Differential Revision: https://phab.mercurial-scm.org/D6562

#!/usr/bin/env bash
# A simple script for opening merge conflicts in the editor.
# Use the following Mercurial settings to enable it.
#
# [ui]
# merge = editmerge
#
# [merge-tools]
# editmerge.args=$output
# editmerge.check=changed
# editmerge.premerge=keep

FILE="$1"

getlines() {
  grep -n "^<<<<<<" "$FILE" | cut -f1 -d:
}

# editor preference loosely based on https://mercurial-scm.org/wiki/editor
# hg showconfig is at the bottom though, since it's slow to run (0.15 seconds)
ED="$HGEDITOR"
if [ "$ED" = "" ] ; then
  ED="$VISUAL"
fi
if [ "$ED" = "" ] ; then
  ED="$EDITOR"
fi
if [ "$ED" = "" ] ; then
  ED="$(hg showconfig ui.editor)"
fi
if [ "$ED" = "" ] ; then
  echo "merge failed - unable to find editor"
  exit 1
fi

if [ "$ED" = "emacs" ] || [ "$ED" = "nano" ] || [ "$ED" = "vim" ] ; then
  FIRSTLINE="$(getlines | head -n 1)"
  PREVIOUSLINE=""

  # open the editor to the first conflict until there are no more
  # or the user stops editing the file
  while [ ! "$FIRSTLINE" = "" ] && [ ! "$FIRSTLINE" = "$PREVIOUSLINE" ] ; do
    $ED "+$FIRSTLINE" "$FILE"
    PREVIOUSLINE="$FIRSTLINE"
    FIRSTLINE="$(getlines | head -n 1)"
  done
else
  $ED "$FILE"
fi

# get the line numbers of the remaining conflicts
CONFLICTS="$(getlines | sed ':a;N;$!ba;s/\n/, /g')"
if [ ! "$CONFLICTS" = "" ] ; then
  echo "merge failed - resolve the conflicts (line $CONFLICTS) then use 'hg resolve --mark'"
  exit 1
fi

exit 0