Add script to test a git sequence of commits.

Signed-off-by: Jacob Kiers <jacob@jacobkiers.net>

bin/git-test-sequence

@@ -0,0 +1,99 @@
+#!/bin/sh
+# Run a command over a sequence of commits.
+# Example:
+#  git test-sequence origin/master.. 'make clean && make test'
+
+. "$(git --exec-path)/git-sh-setup"
+require_work_tree
+
+t=
+force=
+run_once=
+ref_name=pass
+
+# The tree must be really really clean.
+if ! git update-index --ignore-submodules --refresh > /dev/null; then
+    echo >&2 "cannot rebase: you have unstaged changes"
+    git diff-files --name-status -r --ignore-submodules -- >&2
+    exit 1
+fi
+diff=$(git diff-index --cached --name-status -r --ignore-submodules HEAD --)
+case "$diff" in
+    ?*) echo >&2 "cannot rebase: your index contains uncommitted changes"
+        echo >&2 "$diff"
+        exit 1
+        ;;
+esac
+
+start_branch=`git rev-parse --symbolic-full-name HEAD | sed s,refs/heads/,,`
+git checkout `git rev-parse HEAD` > /dev/null 2>/dev/null
+
+cleanup() {
+    git checkout $start_branch > /dev/null 2>/dev/null
+}
+
+already_passed() {
+    obdata=${ref_name}-$t-$1
+    obhash=`echo $obdata | git hash-object --stdin`
+    git cat-file blob $obhash > /dev/null 2>/dev/null \
+        && echo "Already ${ref_name} $1"
+}
+
+passed_on() {
+    obdata=${ref_name}-$t-$1
+    echo $obdata | git hash-object -w --stdin > /dev/null
+    echo "Passed: $1."
+}
+
+broke_on() {
+    git log --pretty="format:Broke on %H (%s)%n" -n 1 $1
+    cleanup
+    exit 1
+}
+
+new_test() {
+    echo "Testing $2"
+    git reset --hard $v && eval "$2" && passed_on $1 || broke_on $v
+    status=$?
+    if test -n "$run_once"; then
+        cleanup
+        exit $status
+    fi
+}
+
+
+while test $# != 0
+do
+    case "$1" in
+        --force)
+            force=yes
+            ;;
+        --once)
+            run_once=yes
+            ;;
+        --ref-name)
+            ref_name=$2
+            shift
+            ;;
+        *)
+            break;
+            ;;
+    esac
+    shift
+done
+
+t=`echo "$2" | git hash-object --stdin`
+
+for v in `git rev-list --reverse $1`
+do
+    tree_ver=`git rev-parse "$v^{tree}"`
+    test -z "$force" && already_passed $tree_ver || new_test $tree_ver "$2"
+done
+cleanup
+
+if test -n "$run_once"; then
+    echo "All commits already passed for --once argument. Quiting."
+    exit 127
+fi
+
+echo "All's well."