contrib/editmergeps.ps1

verify: allow the storage to signal when renames can be tested on `skipread`

This applies the new marker in the lfs handler to show it in action, and adds
the test mentioned at the beginning of the series to show that fulltext isn't
necessary in the LFS case.

The existing `skipread` isn't enough, because it is also set if an error occurs
reading the revlog data, or the data is censored.  It could probably be cleared,
but then it technically violates the interface contract.  That wouldn't matter
for the existing verify algorithm, but it isn't clear how that will change as
alternate storage support is added.

The flag is probably pretty revlog specific, given the comments in verify.py.
But there's already filelog specific stuff in there and I'm not sure what future
storage will bring, so I don't want to over-engineer this.  Likewise, I'm not
sure that we want the verify method for each storage type to completely drive
the bus when it comes to detecting renames, so I don't want to go down the
rabbithole of having verifyintegrity() return metadata hints at this point.

Differential Revision: https://phab.mercurial-scm.org/D7713

# A simple script for opening merge conflicts in editor
# A loose translation of contrib/editmerge to powershell
# Please make sure that both editmergeps.bat and editmerge.ps1 are available
# via %PATH% and use the following Mercurial settings to enable it
#
# [ui]
# editmergeps
# editmergeps.args=$output
# editmergeps.check=changed
# editmergeps.premerge=keep

$file=$args[0]

function Get-Lines
{
  Select-String "^<<<<<<" $file | % {"$($_.LineNumber)"}
}

$ed = $Env:HGEDITOR;
if ($ed -eq $nil)
{
  $ed = $Env:VISUAL;
}
if ($ed -eq $nil)
{
  $ed = $Env:EDITOR;
}
if ($ed -eq $nil)
{
  $ed = $(hg showconfig ui.editor);
}
if ($ed -eq $nil)
{
  Write-Error "merge failed - unable to find editor"
  exit 1
}

if (($ed -eq "vim") -or ($ed -eq "emacs") -or `
    ($ed -eq "nano") -or ($ed -eq "notepad++"))
{
  $lines = Get-Lines
  $firstline = if ($lines.Length -gt 0) { $lines[0] } else { $nil }
  $previousline = $nil;


  # open the editor to the first conflict until there are no more
  # or the user stops editing the file
  while (($firstline -ne $nil) -and ($firstline -ne $previousline))
  {
    if ($ed -eq "notepad++")
    {
        $linearg = "-n$firstline"
    }
    else
    {
        $linearg = "+$firstline"
    }

    Start-Process -Wait -NoNewWindow $ed $linearg,$file
    $previousline = $firstline
    $lines = Get-Lines
    $firstline = if ($lines.Length -gt 0) { $lines[0] } else { $nil }
  }
}
else
{
  & "$ed" $file
}

$conflicts=Get-Lines
if ($conflicts.Length -ne 0)
{
  Write-Output "merge failed - resolve the conflicts (line $conflicts) then use 'hg resolve --mark'"
  exit 1
}

exit 0