test all(?) combinations of content (even file<->dir), skipWorktree bits, sparse-checkout content during a git checkout

testAllCheckoutSituations.sh

#!/bin/bash
#
# Sets up a lot of repos to test git-checkout operations. Setup test repos for all (?) possible
# combinations of contents in merge commit, index, workingtree and also for all combinations 
# of skip-worktree bit and .git/info/sparse-checkout content
# After the repos are setup try to checkout and print status regarding worktree content, HEAD
# 
# Requires that there is an executable 'jgit' in $PATH which is the command-line version 
#
# usage: testAllCheckoutSituations.sh [-jgit]

for merge in 0 a D ;do
  for index in 0 a bb ;do
    for work in 0 a bb ccc D ;do
      for oldSWBit in true false ;do
        for newSWBit in true false ;do
          testCaseName=repo_$merge$index$work$oldSWBit$newSWBit
          (
            # Ignore redundant tests
            [ $index == bb -a $merge != a ] && continue
            [ $work == ccc -a $index != bb ] && continue
            [ $index == 0 -a $oldSWBit == true ] && continue

            echo "############################# $testCaseName"
            # Create new repo, configure sparseCheckout, create initial commit
            rm -fr $testCaseName
            git init -q $testCaseName
            cd $testCaseName
            git config core.sparsecheckout true

            # Create the 'MERGE' commit which should be checked out
            [ $merge == a ] && echo $merge >f
            [ $merge == D ] && mkdir f && echo $merge >f/f2
            [ -e f ] && git add f
            git commit -q -mMERGE --allow-empty
            git tag MERGE

            # Create the index (including skipWorktree bit) and the sparse-checkout file
            if [ $merge != $index ] ;then
              if [ $index == 0 ] ;then
                git rm -fqr f
              else
                [ -d f ] && rm -fr f
                echo $index >f
                git add f
              fi
            fi
            [ $index != 0 -a $oldSWBit == true ] && git update-index --skip-worktree f
            [ $newSWBit == true ] && echo f >.git/info/sparse-checkout

            # Create the workingTree
            if [ $index != $work ] ;then
              if [ $work == D ] ;then
                rm -fr f
                mkdir f; echo $merge >f/f2
              elif [ $work == 0 ] ;then
                rm -fr f
              else
                [ -d f ] && rm -fr f
                echo $work >f
              fi
            fi

            # print the status before the checkout
            echo "State before checkout"
            [ $index != 0 ] && echo "index state:"
            [ $index != 0 ] && git ls-files -sv --debug | grep -v "ctime:\|mtime:\|dev:"
            [ $index != 0 ] && echo "index content: " && git show :f
            [ $merge != 0 ] && echo "content in MERGE: " && git show MERGE:f
	    [ -e f ] && echo "worktree content: " && ls -l f | cut -d' ' -f1-8 && cat f
            [ -f .git/info/sparse-checkout ] && echo "sparse-checkout content: " && cat .git/info/sparse-checkout 

            # now try to checkout
            if [ "$1" == "-jgit" ] ;then
              jgit checkout -f MERGE
            else
              git checkout -q -f MERGE
            fi

            # print the status
            echo "State after checkout with rc=$?"
            echo "HEAD: " $(git describe --all)
            if  git ls-files -q --error-unmatch -- f >/dev/null 2>&1 ;then
              echo "index state:"
              git ls-files -sv --debug | grep -v "ctime:\|mtime:\|dev:"
              echo "index content: " && git show :f
            fi
	    [ -e f ] && echo "worktree content: " && ls -l f | cut -d' ' -f1-8 && cat f
          )
        done
      done
    done
  done
done