# genmerges is the workhorse of the test-merge-combination-*.t tests.

# Given:

# - a `range` function describing the possible values for file a

# - a `isgood` function to filter out uninteresting combination

# - a `createfile` function to actually write the values for file a on the

#   filesystem

#

# it print a series of lines that look like: abcd C: output of -T {files}

# describing the file a at respectively the base, p2, p1, merge

# revision. "C" indicates that hg merge had conflicts.

genmerges () {

  (LC_ALL=C type range | grep -q 'function') || (echo >&2 "missing function: range")

  (LC_ALL=C type isgood | grep -q 'function') || (echo >&2 "missing function: isgood")

  (LC_ALL=C type createfile | grep -q 'function') || (echo >&2 "missing function: createfile")

  for base in `range` -; do

    for r1 in `range $base` -; do

      for r2 in `range $base $r1` -; do

        for m in `range $base $r1 $r2` -; do

          line="$base$r1$r2$m"

          isgood $line || continue

          hg init repo

          cd repo

          make_commit () {

            v=$1; msg=$2; file=$3;

            if [ $v != - ]; then

              createfile $v

            else

              if [ -f a ]

              then rm a

              else touch $file

              fi

            fi

            hg commit -q -Am $msg || exit 123

          }

          echo foo > foo

          make_commit $base base b

          make_commit $r1 r1 c

          hg up -r 0 -q

          make_commit $r2 r2 d

          hg merge -q -r 1 > ../output 2>&1

          if [ $? -ne 0 ]; then rm -f *.orig; hg resolve -m --all -q; fi

          if [ -s ../output ]; then conflicts=" C"; else conflicts="  "; fi

          make_commit $m m e

          if [ $m = $r1 ] && [ $m = $r2 ]

          then expected=

          elif [ $m = $r1 ]

          then if [ $base = $r2 ]

               then expected=

               else expected=a

               fi

          elif [ $m = $r2 ]

          then if [ $base = $r1 ]

               then expected=

               else expected=a

               fi

          else expected=a

          fi

          got=`hg log -r 3 --template '{files}\n' | tr -d 'e '`

          if [ "$got" = "$expected" ]

          then echo "$line$conflicts: agree on \"$got\""

          else echo "$line$conflicts: hg said \"$got\", expected \"$expected\""

          fi

          cd ../

          rm -rf repo

        done

      done

    done

  done

}