chiark / gitweb /
Merge branch 'i/build' into refs/top-bases/i/basis-merge
[topgit.git] / tg-export.sh
index dea24d9..d68a6ac 100644 (file)
@@ -27,8 +27,10 @@ while [ -n "$1" ]; do
                driver=quilt;;
        --collapse)
                driver=collapse;;
+       --linearize)
+               driver=linearize;;
        -*)
-               echo "Usage: tg [...] export ([--collapse] NEWBRANCH | [-b BRANCH1,BRANCH2...] --quilt DIRECTORY)" >&2
+               echo "Usage: tg [...] export ([--collapse] NEWBRANCH | [-b BRANCH1,BRANCH2...] --quilt DIRECTORY | --linearize NEWBRANCH)" >&2
                exit 1;;
        *)
                [ -z "$output" ] || die "output already specified ($output)"
@@ -52,25 +54,20 @@ if [ -z "$branches" ]; then
        name="$(git symbolic-ref HEAD | sed 's#^refs/heads/##')"
        base_rev="$(git rev-parse --short --verify "refs/top-bases/$name" 2>/dev/null)" ||
                die "not on a TopGit-controlled branch"
+       branches="$name"
+else
+       name="${branches##*,}" # the last of the comma-separated items
 fi
+# $name holds the current branch
+# $branches holds the comma-separated list of branches
+# $name is equal to the last of the list of branches
 
 
-playground="$(mktemp -d -t tg-export.XXXXXX)"
-trap 'rm -rf "$playground"' EXIT
+playground="$(get_temp tg-export -d)"
 
 
 ## Collapse driver
 
-# pretty_tree NAME
-# Output tree ID of a cleaned-up tree without tg's artifacts.
-pretty_tree()
-{
-       (export GIT_INDEX_FILE="$playground/^index"
-        git read-tree "$1"
-        git update-index --force-remove ".topmsg" ".topdeps"
-        git write-tree)
-}
-
 create_tg_commit()
 {
        name="$1"
@@ -98,7 +95,7 @@ create_tg_commit()
 # Produce a collapsed commit of branch NAME.
 collapsed_commit()
 {
-       name="$1"
+       local name; name="$1"
 
        rm -f "$playground/^pre" "$playground/^post"
        >"$playground/^body"
@@ -111,7 +108,7 @@ collapsed_commit()
                        echo "TopGit-driven merge of branches:"
                        echo
                        cut -f 2 "$playground/$name^parents"
-               } | git commit-tree "$(pretty_tree "refs/top-bases/$name")" \
+               } | git commit-tree "$(pretty_tree "$name" -b)" \
                        $(for p in $parent; do echo -p $p; done))"
        fi
 
@@ -183,8 +180,8 @@ quilt()
                echo "Skip empty patch $_dep";
        else
                if "$numbered"; then
-                       number="$(printf "%04u" $(($(cat "$playground/^number" 2>/dev/null) + 1)))";
-                       bn="$number-$bn";
+                       number="$(echo $(($(cat "$playground/^number" 2>/dev/null) + 1)))";
+                       bn="$(printf "%04u-$bn" $number)";
                        echo "$number" >"$playground/^number";
                fi;
 
@@ -195,10 +192,63 @@ quilt()
        fi
 }
 
+linearize()
+{
+       if test ! -f "$playground/^BASE"; then
+               head="$(git rev-parse --verify "$_dep")"
+               echo "$head" > "$playground/^BASE"
+               git checkout -q "$head"
+               return;
+       fi;
+
+       head=$(git rev-parse --verify HEAD)
+
+       if [ -z "$_dep_is_tgish" ]; then
+               # merge in $_dep unless already included
+               rev="$(git rev-parse --verify "$_dep")";
+               common="$(git merge-base --all HEAD "$_dep")";
+               if test "$rev" = "$common"; then
+                       # already included, just skip
+                       :;
+               else
+                       retmerge=0;
+
+                       git merge -s recursive "$_dep" || retmerge="$?";
+                       if test "x$retmerge" != "x0"; then
+                               echo fix up the merge, commit and then exit;
+                               #todo error handling
+                               sh -i </dev/tty;
+                       fi;
+               fi;
+       else
+               retmerge=0;
+
+               git merge-recursive "$(pretty_tree "$_dep" -b)" -- HEAD "$(pretty_tree "refs/heads/$_dep")" || retmerge="$?";
+
+               if test "x$retmerge" != "x0"; then
+                       git rerere;
+                       echo "fix up the merge and update the index.  Don't commit!"
+                       #todo error handling
+                       sh -i </dev/tty;
+               fi
+
+               result_tree=$(git write-tree)
+               # testing branch_empty might not always give the right answer.
+               # It can happen that the patch is non-empty but still after
+               # linearizing there is no change.  So compare the trees.
+               if test "x$result_tree" = "x$(git rev-parse $head^{tree})"; then
+                       echo "skip empty commit $_dep";
+               else
+                       newcommit=$(create_tg_commit "$_dep" "$result_tree" HEAD)
+                       git update-ref HEAD $newcommit $head
+                       echo "exported commit $_dep";
+               fi
+       fi
+}
 
 ## Machinery
 
-if [ "$driver" = "collapse" ]; then
+if [ "$driver" = "collapse" ] || [ "$driver" = "linearize" ]; then
        [ -n "$output" ] ||
                die "no target branch specified"
        ! ref_exists "$output"  ||
@@ -226,17 +276,10 @@ driver()
 
 # Call driver on all the branches - this will happen
 # in topological order.
-if [ -z "$branches" ]; then
+echo "$branches" | tr , '\n' | while read name; do
        recurse_deps driver "$name"
        (_ret=0; _dep="$name"; _name=""; _dep_is_tgish=1; driver)
-else
-       echo "$branches" | tr ',' '\n' | while read _dep; do
-               _dep_is_tgish=1
-               $driver
-       done
-       name="$(echo "$branches" | sed 's/.*,//')"
-fi
-
+done
 
 if [ "$driver" = "collapse" ]; then
        git update-ref "refs/heads/$output" "$(cat "$playground/$name")" ""
@@ -247,6 +290,17 @@ if [ "$driver" = "collapse" ]; then
 elif [ "$driver" = "quilt" ]; then
        depcount="$(cat "$output/series" | wc -l)"
        echo "Exported topic branch $name (total $depcount topics) to directory $output"
+
+elif [ "$driver" = "linearize" ]; then
+       git checkout -q -b $output
+
+       echo $name
+       if test $(git rev-parse "$(pretty_tree $name)^{tree}") != $(git rev-parse "HEAD^{tree}"); then
+               echo "Warning: Exported result doesn't match";
+               echo "tg-head=$(git rev-parse "$name"), exported=$(git rev-parse "HEAD")";
+               #git diff $head HEAD;
+       fi;
+
 fi
 
 # vim:noet