Automate with:

find Tests -type f -print0 | xargs -0 perl -i -0pe \
's/set\(([a-zA-Z0-9_]+)(\s+)"\$\{\1\}([^"])/string(APPEND \1\2"\3/g'

Make RETURN_VALUE report -1 if the update command failed as the
documentation claims.  Also avoid reporting a ctest script-level failure
if the update command fails because we still correctly administered the
update step.

Ancient versions of CMake required else(), endif(), and similar block
termination commands to have arguments matching the command starting the
block.  This is no longer the preferred style.

Run the following shell code:

for c in else endif endforeach endfunction endmacro endwhile; do
    echo 's/\b'"$c"'\(\s*\)(.\+)/'"$c"'\1()/'
done >convert.sed &&
git ls-files -z -- bootstrap '*.cmake' '*.cmake.in' '*CMakeLists.txt' |
egrep -z -v '^(Utilities/cm|Source/kwsys/)' |
egrep -z -v 'Tests/CMakeTests/While-Endwhile-' |
xargs -0 sed -i -f convert.sed &&
rm convert.sed

Use "file:///..." instead of "file:////..." when the file system path
starts in a slash.  Commit 0916cc88 (CTest.UpdateHG: Fix repo URL for
local filesystem, 2012-03-02) added a third slash after "file://"
unconditionally.  This worked for many file systems but not on Cygwin
where "file:////cygdrive/..." looks like "file://" followed by a network
file path "//cygdrive/...".  Add the slash only if the file system path
does not already start with one.

Use "file:///c:/" instead of "file://c:/" because the latter
looks like a machine:port URL instead of a local file URL.

Teach (create|run)_dashboard_script macros to treat the argument as the
name of a build tree.  Append '.cmake' to generate the dashboard script
name.  This allows future re-use of the macros for multiple test
scripts.

This creates cmCTestHG to drive CTest Update handling on hg-based work
trees.  Currently we always update to the head of the remote tracking
branch (hg pull), so the nightly start time is ignored for Nightly
builds.  A later change will address this.

See issue #7879.  Patch from Emmanuel Christophe.  I modified the patch
slightly for code style, to finish up some parsing details, and to fix
the test.