Merge branch 'jk/rebase-i-drop-ident-check' into maint
[gitweb.git] / contrib / subtree / git-subtree.sh
index 7a39b30ad09483ef9796d98ca78e52f652046582..dec085a235f4477c9079dc643c76db166f487761 100755 (executable)
@@ -4,8 +4,9 @@
 #
 # Copyright (C) 2009 Avery Pennarun <apenwarr@gmail.com>
 #
-if [ $# -eq 0 ]; then
-    set -- -h
+if test $# -eq 0
+then
+       set -- -h
 fi
 OPTS_SPEC="\
 git subtree add   --prefix=<prefix> <commit>
@@ -48,89 +49,144 @@ squash=
 message=
 prefix=
 
-debug()
-{
-       if [ -n "$debug" ]; then
+debug () {
+       if test -n "$debug"
+       then
                printf "%s\n" "$*" >&2
        fi
 }
 
-say()
-{
-       if [ -z "$quiet" ]; then
+say () {
+       if test -z "$quiet"
+       then
                printf "%s\n" "$*" >&2
        fi
 }
 
-progress()
-{
-       if [ -z "$quiet" ]; then
+progress () {
+       if test -z "$quiet"
+       then
                printf "%s\r" "$*" >&2
        fi
 }
 
-assert()
-{
-       if "$@"; then
-               :
-       else
+assert () {
+       if ! "$@"
+       then
                die "assertion failed: " "$@"
        fi
 }
 
 
-#echo "Options: $*"
-
-while [ $# -gt 0 ]; do
+while test $# -gt 0
+do
        opt="$1"
        shift
+
        case "$opt" in
-               -q) quiet=1 ;;
-               -d) debug=1 ;;
-               --annotate) annotate="$1"; shift ;;
-               --no-annotate) annotate= ;;
-               -b) branch="$1"; shift ;;
-               -P) prefix="${1%/}"; shift ;;
-               -m) message="$1"; shift ;;
-               --no-prefix) prefix= ;;
-               --onto) onto="$1"; shift ;;
-               --no-onto) onto= ;;
-               --rejoin) rejoin=1 ;;
-               --no-rejoin) rejoin= ;;
-               --ignore-joins) ignore_joins=1 ;;
-               --no-ignore-joins) ignore_joins= ;;
-               --squash) squash=1 ;;
-               --no-squash) squash= ;;
-               --) break ;;
-               *) die "Unexpected option: $opt" ;;
+       -q)
+               quiet=1
+               ;;
+       -d)
+               debug=1
+               ;;
+       --annotate)
+               annotate="$1"
+               shift
+               ;;
+       --no-annotate)
+               annotate=
+               ;;
+       -b)
+               branch="$1"
+               shift
+               ;;
+       -P)
+               prefix="${1%/}"
+               shift
+               ;;
+       -m)
+               message="$1"
+               shift
+               ;;
+       --no-prefix)
+               prefix=
+               ;;
+       --onto)
+               onto="$1"
+               shift
+               ;;
+       --no-onto)
+               onto=
+               ;;
+       --rejoin)
+               rejoin=1
+               ;;
+       --no-rejoin)
+               rejoin=
+               ;;
+       --ignore-joins)
+               ignore_joins=1
+               ;;
+       --no-ignore-joins)
+               ignore_joins=
+               ;;
+       --squash)
+               squash=1
+               ;;
+       --no-squash)
+               squash=
+               ;;
+       --)
+               break
+               ;;
+       *)
+               die "Unexpected option: $opt"
+               ;;
        esac
 done
 
 command="$1"
 shift
+
 case "$command" in
-       add|merge|pull) default= ;;
-       split|push) default="--default HEAD" ;;
-       *) die "Unknown command '$command'" ;;
+add|merge|pull)
+       default=
+       ;;
+split|push)
+       default="--default HEAD"
+       ;;
+*)
+       die "Unknown command '$command'"
+       ;;
 esac
 
-if [ -z "$prefix" ]; then
+if test -z "$prefix"
+then
        die "You must provide the --prefix option."
 fi
 
 case "$command" in
-       add) [ -e "$prefix" ] && 
-               die "prefix '$prefix' already exists." ;;
-       *)   [ -e "$prefix" ] || 
-               die "'$prefix' does not exist; use 'git subtree add'" ;;
+add)
+       test -e "$prefix" &&
+               die "prefix '$prefix' already exists."
+       ;;
+*)
+       test -e "$prefix" ||
+               die "'$prefix' does not exist; use 'git subtree add'"
+       ;;
 esac
 
 dir="$(dirname "$prefix/.")"
 
-if [ "$command" != "pull" -a "$command" != "add" -a "$command" != "push" ]; then
+if test "$command" != "pull" &&
+               test "$command" != "add" &&
+               test "$command" != "push"
+then
        revs=$(git rev-parse $default --revs-only "$@") || exit $?
-       dirs="$(git rev-parse --no-revs --no-flags "$@")" || exit $?
-       if [ -n "$dirs" ]; then
+       dirs=$(git rev-parse --no-revs --no-flags "$@") || exit $?
+       if test -n "$dirs"
+       then
                die "Error: Use --prefix instead of bare filenames."
        fi
 fi
@@ -142,78 +198,82 @@ debug "dir: {$dir}"
 debug "opts: {$*}"
 debug
 
-cache_setup()
-{
+cache_setup () {
        cachedir="$GIT_DIR/subtree-cache/$$"
-       rm -rf "$cachedir" || die "Can't delete old cachedir: $cachedir"
-       mkdir -p "$cachedir" || die "Can't create new cachedir: $cachedir"
-       mkdir -p "$cachedir/notree" || die "Can't create new cachedir: $cachedir/notree"
+       rm -rf "$cachedir" ||
+               die "Can't delete old cachedir: $cachedir"
+       mkdir -p "$cachedir" ||
+               die "Can't create new cachedir: $cachedir"
+       mkdir -p "$cachedir/notree" ||
+               die "Can't create new cachedir: $cachedir/notree"
        debug "Using cachedir: $cachedir" >&2
 }
 
-cache_get()
-{
-       for oldrev in $*; do
-               if [ -r "$cachedir/$oldrev" ]; then
+cache_get () {
+       for oldrev in "$@"
+       do
+               if test -r "$cachedir/$oldrev"
+               then
                        read newrev <"$cachedir/$oldrev"
                        echo $newrev
                fi
        done
 }
 
-cache_miss()
-{
-       for oldrev in $*; do
-               if [ ! -r "$cachedir/$oldrev" ]; then
+cache_miss () {
+       for oldrev in "$@"
+       do
+               if ! test -r "$cachedir/$oldrev"
+               then
                        echo $oldrev
                fi
        done
 }
 
-check_parents()
-{
-       missed=$(cache_miss $*)
-       for miss in $missed; do
-               if [ ! -r "$cachedir/notree/$miss" ]; then
+check_parents () {
+       missed=$(cache_miss "$@")
+       for miss in $missed
+       do
+               if ! test -r "$cachedir/notree/$miss"
+               then
                        debug "  incorrect order: $miss"
                fi
        done
 }
 
-set_notree()
-{
+set_notree () {
        echo "1" > "$cachedir/notree/$1"
 }
 
-cache_set()
-{
+cache_set () {
        oldrev="$1"
        newrev="$2"
-       if [ "$oldrev" != "latest_old" \
-            -a "$oldrev" != "latest_new" \
-            -a -e "$cachedir/$oldrev" ]; then
+       if test "$oldrev" != "latest_old" &&
+               test "$oldrev" != "latest_new" &&
+               test -e "$cachedir/$oldrev"
+       then
                die "cache for $oldrev already exists!"
        fi
        echo "$newrev" >"$cachedir/$oldrev"
 }
 
-rev_exists()
-{
-       if git rev-parse "$1" >/dev/null 2>&1; then
+rev_exists () {
+       if git rev-parse "$1" >/dev/null 2>&1
+       then
                return 0
        else
                return 1
        fi
 }
 
-rev_is_descendant_of_branch()
-{
+rev_is_descendant_of_branch () {
        newrev="$1"
        branch="$2"
-       branch_hash=$(git rev-parse $branch)
-       match=$(git rev-list -1 $branch_hash ^$newrev)
+       branch_hash=$(git rev-parse "$branch")
+       match=$(git rev-list -1 "$branch_hash" "^$newrev")
 
-       if [ -z "$match" ]; then
+       if test -z "$match"
+       then
                return 0
        else
                return 1
@@ -223,15 +283,14 @@ rev_is_descendant_of_branch()
 # if a commit doesn't have a parent, this might not work.  But we only want
 # to remove the parent from the rev-list, and since it doesn't exist, it won't
 # be there anyway, so do nothing in that case.
-try_remove_previous()
-{
-       if rev_exists "$1^"; then
+try_remove_previous () {
+       if rev_exists "$1^"
+       then
                echo "^$1^"
        fi
 }
 
-find_latest_squash()
-{
+find_latest_squash () {
        debug "Looking for latest squash ($dir)..."
        dir="$1"
        sq=
@@ -239,37 +298,43 @@ find_latest_squash()
        sub=
        git log --grep="^git-subtree-dir: $dir/*\$" \
                --pretty=format:'START %H%n%s%n%n%b%nEND%n' HEAD |
-       while read a b junk; do
+       while read a b junk
+       do
                debug "$a $b $junk"
                debug "{{$sq/$main/$sub}}"
                case "$a" in
-                       START) sq="$b" ;;
-                       git-subtree-mainline:) main="$b" ;;
-                       git-subtree-split:)
-                               sub="$(git rev-parse "$b^0")" ||
-                                   die "could not rev-parse split hash $b from commit $sq"
-                               ;;
-                       END)
-                               if [ -n "$sub" ]; then
-                                       if [ -n "$main" ]; then
-                                               # a rejoin commit?
-                                               # Pretend its sub was a squash.
-                                               sq="$sub"
-                                       fi
-                                       debug "Squash found: $sq $sub"
-                                       echo "$sq" "$sub"
-                                       break
+               START)
+                       sq="$b"
+                       ;;
+               git-subtree-mainline:)
+                       main="$b"
+                       ;;
+               git-subtree-split:)
+                       sub="$(git rev-parse "$b^0")" ||
+                       die "could not rev-parse split hash $b from commit $sq"
+                       ;;
+               END)
+                       if test -n "$sub"
+                       then
+                               if test -n "$main"
+                               then
+                                       # a rejoin commit?
+                                       # Pretend its sub was a squash.
+                                       sq="$sub"
                                fi
-                               sq=
-                               main=
-                               sub=
-                               ;;
+                               debug "Squash found: $sq $sub"
+                               echo "$sq" "$sub"
+                               break
+                       fi
+                       sq=
+                       main=
+                       sub=
+                       ;;
                esac
        done
 }
 
-find_existing_splits()
-{
+find_existing_splits () {
        debug "Looking for prior splits..."
        dir="$1"
        revs="$2"
@@ -277,37 +342,43 @@ find_existing_splits()
        sub=
        git log --grep="^git-subtree-dir: $dir/*\$" \
                --pretty=format:'START %H%n%s%n%n%b%nEND%n' $revs |
-       while read a b junk; do
+       while read a b junk
+       do
                case "$a" in
-                       START) sq="$b" ;;
-                       git-subtree-mainline:) main="$b" ;;
-                       git-subtree-split:)
-                               sub="$(git rev-parse "$b^0")" ||
-                                   die "could not rev-parse split hash $b from commit $sq"
-                               ;;
-                       END)
-                               debug "  Main is: '$main'"
-                               if [ -z "$main" -a -n "$sub" ]; then
-                                       # squash commits refer to a subtree
-                                       debug "  Squash: $sq from $sub"
-                                       cache_set "$sq" "$sub"
-                               fi
-                               if [ -n "$main" -a -n "$sub" ]; then
-                                       debug "  Prior: $main -> $sub"
-                                       cache_set $main $sub
-                                       cache_set $sub $sub
-                                       try_remove_previous "$main"
-                                       try_remove_previous "$sub"
-                               fi
-                               main=
-                               sub=
-                               ;;
+               START)
+                       sq="$b"
+                       ;;
+               git-subtree-mainline:)
+                       main="$b"
+                       ;;
+               git-subtree-split:)
+                       sub="$(git rev-parse "$b^0")" ||
+                       die "could not rev-parse split hash $b from commit $sq"
+                       ;;
+               END)
+                       debug "  Main is: '$main'"
+                       if test -z "$main" -a -n "$sub"
+                       then
+                               # squash commits refer to a subtree
+                               debug "  Squash: $sq from $sub"
+                               cache_set "$sq" "$sub"
+                       fi
+                       if test -n "$main" -a -n "$sub"
+                       then
+                               debug "  Prior: $main -> $sub"
+                               cache_set $main $sub
+                               cache_set $sub $sub
+                               try_remove_previous "$main"
+                               try_remove_previous "$sub"
+                       fi
+                       main=
+                       sub=
+                       ;;
                esac
        done
 }
 
-copy_commit()
-{
+copy_commit () {
        # We're going to set some environment vars here, so
        # do it in a subshell to get rid of them safely later
        debug copy_commit "{$1}" "{$2}" "{$3}"
@@ -325,66 +396,69 @@ copy_commit()
                        GIT_COMMITTER_NAME \
                        GIT_COMMITTER_EMAIL \
                        GIT_COMMITTER_DATE
-               (printf "%s" "$annotate"; cat ) |
+               (
+                       printf "%s" "$annotate"
+                       cat
+               ) |
                git commit-tree "$2" $3  # reads the rest of stdin
        ) || die "Can't copy commit $1"
 }
 
-add_msg()
-{
+add_msg () {
        dir="$1"
        latest_old="$2"
        latest_new="$3"
-       if [ -n "$message" ]; then
+       if test -n "$message"
+       then
                commit_message="$message"
        else
                commit_message="Add '$dir/' from commit '$latest_new'"
        fi
        cat <<-EOF
                $commit_message
-               
+
                git-subtree-dir: $dir
                git-subtree-mainline: $latest_old
                git-subtree-split: $latest_new
        EOF
 }
 
-add_squashed_msg()
-{
-       if [ -n "$message" ]; then
+add_squashed_msg () {
+       if test -n "$message"
+       then
                echo "$message"
        else
                echo "Merge commit '$1' as '$2'"
        fi
 }
 
-rejoin_msg()
-{
+rejoin_msg () {
        dir="$1"
        latest_old="$2"
        latest_new="$3"
-       if [ -n "$message" ]; then
+       if test -n "$message"
+       then
                commit_message="$message"
        else
                commit_message="Split '$dir/' into commit '$latest_new'"
        fi
        cat <<-EOF
                $commit_message
-               
+
                git-subtree-dir: $dir
                git-subtree-mainline: $latest_old
                git-subtree-split: $latest_new
        EOF
 }
 
-squash_msg()
-{
+squash_msg () {
        dir="$1"
        oldsub="$2"
        newsub="$3"
        newsub_short=$(git rev-parse --short "$newsub")
-       
-       if [ -n "$oldsub" ]; then
+
+       if test -n "$oldsub"
+       then
                oldsub_short=$(git rev-parse --short "$oldsub")
                echo "Squashed '$dir/' changes from $oldsub_short..$newsub_short"
                echo
@@ -393,41 +467,41 @@ squash_msg()
        else
                echo "Squashed '$dir/' content from commit $newsub_short"
        fi
-       
+
        echo
        echo "git-subtree-dir: $dir"
        echo "git-subtree-split: $newsub"
 }
 
-toptree_for_commit()
-{
+toptree_for_commit () {
        commit="$1"
        git log -1 --pretty=format:'%T' "$commit" -- || exit $?
 }
 
-subtree_for_commit()
-{
+subtree_for_commit () {
        commit="$1"
        dir="$2"
        git ls-tree "$commit" -- "$dir" |
-       while read mode type tree name; do
-               assert [ "$name" = "$dir" ]
-               assert [ "$type" = "tree" -o "$type" = "commit" ]
-               [ "$type" = "commit" ] && continue  # ignore submodules
+       while read mode type tree name
+       do
+               assert test "$name" = "$dir"
+               assert test "$type" = "tree" -o "$type" = "commit"
+               test "$type" = "commit" && continue  # ignore submodules
                echo $tree
                break
        done
 }
 
-tree_changed()
-{
+tree_changed () {
        tree=$1
        shift
-       if [ $# -ne 1 ]; then
+       if test $# -ne 1
+       then
                return 0   # weird parents, consider it changed
        else
                ptree=$(toptree_for_commit $1)
-               if [ "$ptree" != "$tree" ]; then
+               if test "$ptree" != "$tree"
+               then
                        return 0   # changed
                else
                        return 1   # not changed
@@ -435,118 +509,127 @@ tree_changed()
        fi
 }
 
-new_squash_commit()
-{
+new_squash_commit () {
        old="$1"
        oldsub="$2"
        newsub="$3"
        tree=$(toptree_for_commit $newsub) || exit $?
-       if [ -n "$old" ]; then
-               squash_msg "$dir" "$oldsub" "$newsub" | 
-                       git commit-tree "$tree" -p "$old" || exit $?
+       if test -n "$old"
+       then
+               squash_msg "$dir" "$oldsub" "$newsub" |
+               git commit-tree "$tree" -p "$old" || exit $?
        else
                squash_msg "$dir" "" "$newsub" |
-                       git commit-tree "$tree" || exit $?
+               git commit-tree "$tree" || exit $?
        fi
 }
 
-copy_or_skip()
-{
+copy_or_skip () {
        rev="$1"
        tree="$2"
        newparents="$3"
-       assert [ -n "$tree" ]
+       assert test -n "$tree"
 
        identical=
        nonidentical=
        p=
        gotparents=
-       for parent in $newparents; do
+       for parent in $newparents
+       do
                ptree=$(toptree_for_commit $parent) || exit $?
-               [ -z "$ptree" ] && continue
-               if [ "$ptree" = "$tree" ]; then
+               test -z "$ptree" && continue
+               if test "$ptree" = "$tree"
+               then
                        # an identical parent could be used in place of this rev.
                        identical="$parent"
                else
                        nonidentical="$parent"
                fi
-               
+
                # sometimes both old parents map to the same newparent;
                # eliminate duplicates
                is_new=1
-               for gp in $gotparents; do
-                       if [ "$gp" = "$parent" ]; then
+               for gp in $gotparents
+               do
+                       if test "$gp" = "$parent"
+                       then
                                is_new=
                                break
                        fi
                done
-               if [ -n "$is_new" ]; then
+               if test -n "$is_new"
+               then
                        gotparents="$gotparents $parent"
                        p="$p -p $parent"
                fi
        done
 
        copycommit=
-       if [ -n "$identical" ] && [ -n "$nonidentical" ]; then
+       if test -n "$identical" && test -n "$nonidentical"
+       then
                extras=$(git rev-list --count $identical..$nonidentical)
-               if [ "$extras" -ne 0 ]; then
+               if test "$extras" -ne 0
+               then
                        # we need to preserve history along the other branch
                        copycommit=1
                fi
        fi
-       if [ -n "$identical" ] && [ -z "$copycommit" ]; then
+       if test -n "$identical" && test -z "$copycommit"
+       then
                echo $identical
        else
-               copy_commit $rev $tree "$p" || exit $?
+               copy_commit "$rev" "$tree" "$p" || exit $?
        fi
 }
 
-ensure_clean()
-{
-       if ! git diff-index HEAD --exit-code --quiet 2>&1; then
+ensure_clean () {
+       if ! git diff-index HEAD --exit-code --quiet 2>&1
+       then
                die "Working tree has modifications.  Cannot add."
        fi
-       if ! git diff-index --cached HEAD --exit-code --quiet 2>&1; then
+       if ! git diff-index --cached HEAD --exit-code --quiet 2>&1
+       then
                die "Index has modifications.  Cannot add."
        fi
 }
 
-ensure_valid_ref_format()
-{
+ensure_valid_ref_format () {
        git check-ref-format "refs/heads/$1" ||
-           die "'$1' does not look like a ref"
+               die "'$1' does not look like a ref"
 }
 
-cmd_add()
-{
-       if [ -e "$dir" ]; then
+cmd_add () {
+       if test -e "$dir"
+       then
                die "'$dir' already exists.  Cannot add."
        fi
 
        ensure_clean
-       
-       if [ $# -eq 1 ]; then
-           git rev-parse -q --verify "$1^{commit}" >/dev/null ||
-           die "'$1' does not refer to a commit"
-
-           "cmd_add_commit" "$@"
-       elif [ $# -eq 2 ]; then
-           # Technically we could accept a refspec here but we're
-           # just going to turn around and add FETCH_HEAD under the
-           # specified directory.  Allowing a refspec might be
-           # misleading because we won't do anything with any other
-           # branches fetched via the refspec.
-           ensure_valid_ref_format "$2"
-
-           "cmd_add_repository" "$@"
+
+       if test $# -eq 1
+       then
+               git rev-parse -q --verify "$1^{commit}" >/dev/null ||
+                       die "'$1' does not refer to a commit"
+
+               cmd_add_commit "$@"
+
+       elif test $# -eq 2
+       then
+               # Technically we could accept a refspec here but we're
+               # just going to turn around and add FETCH_HEAD under the
+               # specified directory.  Allowing a refspec might be
+               # misleading because we won't do anything with any other
+               # branches fetched via the refspec.
+               ensure_valid_ref_format "$2"
+
+               cmd_add_repository "$@"
        else
-           say "error: parameters were '$@'"
-           die "Provide either a commit or a repository and commit."
+               say "error: parameters were '$@'"
+               die "Provide either a commit or a repository and commit."
        fi
 }
 
-cmd_add_repository()
-{
+cmd_add_repository () {
        echo "git fetch" "$@"
        repository=$1
        refspec=$2
@@ -556,60 +639,63 @@ cmd_add_repository()
        cmd_add_commit "$@"
 }
 
-cmd_add_commit()
-{
+cmd_add_commit () {
        revs=$(git rev-parse $default --revs-only "$@") || exit $?
        set -- $revs
        rev="$1"
-       
+
        debug "Adding $dir as '$rev'..."
        git read-tree --prefix="$dir" $rev || exit $?
        git checkout -- "$dir" || exit $?
        tree=$(git write-tree) || exit $?
-       
+
        headrev=$(git rev-parse HEAD) || exit $?
-       if [ -n "$headrev" -a "$headrev" != "$rev" ]; then
+       if test -n "$headrev" && test "$headrev" != "$rev"
+       then
                headp="-p $headrev"
        else
                headp=
        fi
-       
-       if [ -n "$squash" ]; then
+
+       if test -n "$squash"
+       then
                rev=$(new_squash_commit "" "" "$rev") || exit $?
                commit=$(add_squashed_msg "$rev" "$dir" |
-                        git commit-tree $tree $headp -p "$rev") || exit $?
+                       git commit-tree "$tree" $headp -p "$rev") || exit $?
        else
                revp=$(peel_committish "$rev") &&
-               commit=$(add_msg "$dir" "$headrev" "$rev" |
-                        git commit-tree $tree $headp -p "$revp") || exit $?
+               commit=$(add_msg "$dir" $headrev "$rev" |
+                       git commit-tree "$tree" $headp -p "$revp") || exit $?
        fi
        git reset "$commit" || exit $?
-       
+
        say "Added dir '$dir'"
 }
 
-cmd_split()
-{
+cmd_split () {
        debug "Splitting $dir..."
        cache_setup || exit $?
-       
-       if [ -n "$onto" ]; then
+
+       if test -n "$onto"
+       then
                debug "Reading history for --onto=$onto..."
                git rev-list $onto |
-               while read rev; do
+               while read rev
+               do
                        # the 'onto' history is already just the subdir, so
                        # any parent we find there can be used verbatim
                        debug "  cache: $rev"
-                       cache_set $rev $rev
+                       cache_set "$rev" "$rev"
                done
        fi
-       
-       if [ -n "$ignore_joins" ]; then
+
+       if test -n "$ignore_joins"
+       then
                unrevs=
        else
                unrevs="$(find_existing_splits "$dir" "$revs")"
        fi
-       
+
        # We can't restrict rev-list to only $dir here, because some of our
        # parents have the $dir contents the root, and those won't match.
        # (and rev-list --follow doesn't seem to solve this)
@@ -618,12 +704,14 @@ cmd_split()
        revcount=0
        createcount=0
        eval "$grl" |
-       while read rev parents; do
+       while read rev parents
+       do
                revcount=$(($revcount + 1))
                progress "$revcount/$revmax ($createcount)"
                debug "Processing commit: $rev"
-               exists=$(cache_get $rev)
-               if [ -n "$exists" ]; then
+               exists=$(cache_get "$rev")
+               if test -n "$exists"
+               then
                        debug "  prior: $exists"
                        continue
                fi
@@ -631,76 +719,89 @@ cmd_split()
                debug "  parents: $parents"
                newparents=$(cache_get $parents)
                debug "  newparents: $newparents"
-               
-               tree=$(subtree_for_commit $rev "$dir")
+
+               tree=$(subtree_for_commit "$rev" "$dir")
                debug "  tree is: $tree"
 
                check_parents $parents
-               
+
                # ugly.  is there no better way to tell if this is a subtree
                # vs. a mainline commit?  Does it matter?
-               if [ -z $tree ]; then
-                       set_notree $rev
-                       if [ -n "$newparents" ]; then
-                               cache_set $rev $rev
+               if test -z "$tree"
+               then
+                       set_notree "$rev"
+                       if test -n "$newparents"
+                       then
+                               cache_set "$rev" "$rev"
                        fi
                        continue
                fi
 
                newrev=$(copy_or_skip "$rev" "$tree" "$newparents") || exit $?
                debug "  newrev is: $newrev"
-               cache_set $rev $newrev
-               cache_set latest_new $newrev
-               cache_set latest_old $rev
+               cache_set "$rev" "$newrev"
+               cache_set latest_new "$newrev"
+               cache_set latest_old "$rev"
        done || exit $?
+
        latest_new=$(cache_get latest_new)
-       if [ -z "$latest_new" ]; then
+       if test -z "$latest_new"
+       then
                die "No new revisions were found"
        fi
-       
-       if [ -n "$rejoin" ]; then
+
+       if test -n "$rejoin"
+       then
                debug "Merging split branch into HEAD..."
                latest_old=$(cache_get latest_old)
                git merge -s ours \
-                       -m "$(rejoin_msg "$dir" $latest_old $latest_new)" \
-                       $latest_new >&2 || exit $?
-       fi
-       if [ -n "$branch" ]; then
-               if rev_exists "refs/heads/$branch"; then
-                       if ! rev_is_descendant_of_branch $latest_new $branch; then
+                       --allow-unrelated-histories \
+                       -m "$(rejoin_msg "$dir" "$latest_old" "$latest_new")" \
+                       "$latest_new" >&2 || exit $?
+       fi
+       if test -n "$branch"
+       then
+               if rev_exists "refs/heads/$branch"
+               then
+                       if ! rev_is_descendant_of_branch "$latest_new" "$branch"
+                       then
                                die "Branch '$branch' is not an ancestor of commit '$latest_new'."
                        fi
                        action='Updated'
                else
                        action='Created'
                fi
-               git update-ref -m 'subtree split' "refs/heads/$branch" $latest_new || exit $?
+               git update-ref -m 'subtree split' \
+                       "refs/heads/$branch" "$latest_new" || exit $?
                say "$action branch '$branch'"
        fi
-       echo $latest_new
+       echo "$latest_new"
        exit 0
 }
 
-cmd_merge()
-{
+cmd_merge () {
        revs=$(git rev-parse $default --revs-only "$@") || exit $?
        ensure_clean
-       
+
        set -- $revs
-       if [ $# -ne 1 ]; then
+       if test $# -ne 1
+       then
                die "You must provide exactly one revision.  Got: '$revs'"
        fi
        rev="$1"
-       
-       if [ -n "$squash" ]; then
+
+       if test -n "$squash"
+       then
                first_split="$(find_latest_squash "$dir")"
-               if [ -z "$first_split" ]; then
+               if test -z "$first_split"
+               then
                        die "Can't squash-merge: '$dir' was never added."
                fi
                set $first_split
                old=$1
                sub=$2
-               if [ "$sub" = "$rev" ]; then
+               if test "$sub" = "$rev"
+               then
                        say "Subtree is already at commit $rev."
                        exit 0
                fi
@@ -710,25 +811,29 @@ cmd_merge()
        fi
 
        version=$(git version)
-       if [ "$version" \< "git version 1.7" ]; then
-               if [ -n "$message" ]; then
-                       git merge -s subtree --message="$message" $rev
+       if test "$version" \< "git version 1.7"
+       then
+               if test -n "$message"
+               then
+                       git merge -s subtree --message="$message" "$rev"
                else
-                       git merge -s subtree $rev
+                       git merge -s subtree "$rev"
                fi
        else
-               if [ -n "$message" ]; then
-                       git merge -Xsubtree="$prefix" --message="$message" $rev
+               if test -n "$message"
+               then
+                       git merge -Xsubtree="$prefix" \
+                               --message="$message" "$rev"
                else
                        git merge -Xsubtree="$prefix" $rev
                fi
        fi
 }
 
-cmd_pull()
-{
-       if [ $# -ne 2 ]; then
-           die "You must provide <repository> <ref>"
+cmd_pull () {
+       if test $# -ne 2
+       then
+               die "You must provide <repository> <ref>"
        fi
        ensure_clean
        ensure_valid_ref_format "$2"
@@ -738,20 +843,21 @@ cmd_pull()
        cmd_merge "$@"
 }
 
-cmd_push()
-{
-       if [ $# -ne 2 ]; then
-           die "You must provide <repository> <ref>"
+cmd_push () {
+       if test $# -ne 2
+       then
+               die "You must provide <repository> <ref>"
        fi
        ensure_valid_ref_format "$2"
-       if [ -e "$dir" ]; then
-           repository=$1
-           refspec=$2
-           echo "git push using: " $repository $refspec
-           localrev=$(git subtree split --prefix="$prefix") || die
-           git push "$repository" $localrev:refs/heads/$refspec
+       if test -e "$dir"
+       then
+               repository=$1
+               refspec=$2
+               echo "git push using: " "$repository" "$refspec"
+               localrev=$(git subtree split --prefix="$prefix") || die
+               git push "$repository" "$localrev":"refs/heads/$refspec"
        else
-           die "'$dir' must already exist. Try 'git subtree add'."
+               die "'$dir' must already exist. Try 'git subtree add'."
        fi
 }