Bisect: teach "bisect start" to optionally use one bad and many good revs.

One bad commit is fundamentally needed for bisect to run,
and if we beforehand know more good commits, we can narrow
the bisect space down without doing the whole tree checkout
every time we give good commits.

This patch implements:

    git bisect start [<bad> [<good>...]] [--] [<pathspec>...]

as a short-hand for this command sequence:

    git bisect start
    git bisect bad $bad
    git bisect good $good1 $good2...

On the other hand, there may be some confusion between revs
(<bad> and <good>...) and <pathspec>... if -- is not used
and if an invalid rev or a pathspec that looks like a rev is
given.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/git-bisect.sh b/git-bisect.sh
index 11313a7949909f61f47ccc061cfc6390b225c630..2e68e3dac0743ca3d7d8d3bd281adcbdaa904f72 100755 (executable)
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -1,15 +1,24 @@
 #!/bin/sh
 
 USAGE='[start|bad|good|next|reset|visualize|replay|log|run]'
-LONG_USAGE='git bisect start [<pathspec>]      reset bisect state and start bisection.
-git bisect bad [<rev>]         mark <rev> a known-bad revision.
-git bisect good [<rev>...]     mark <rev>... known-good revisions.
-git bisect next                        find next bisection to test and check it out.
-git bisect reset [<branch>]    finish bisection search and go back to branch.
-git bisect visualize            show bisect status in gitk.
-git bisect replay <logfile>    replay bisection log.
-git bisect log                 show bisect log.
-git bisect run <cmd>...        use <cmd>... to automatically bisect.'
+LONG_USAGE='git bisect start [<bad> [<good>...]] [--] [<pathspec>...]
+        reset bisect state and start bisection.
+git bisect bad [<rev>]
+        mark <rev> a known-bad revision.
+git bisect good [<rev>...]
+        mark <rev>... known-good revisions.
+git bisect next
+        find next bisection to test and check it out.
+git bisect reset [<branch>]
+        finish bisection search and go back to branch.
+git bisect visualize
+        show bisect status in gitk.
+git bisect replay <logfile>
+        replay bisection log.
+git bisect log
+        show bisect log.
+git bisect run <cmd>...
+        use <cmd>... to automatically bisect.'
 
 . git-sh-setup
 require_work_tree
@@ -70,14 +79,48 @@ bisect_start() {
        #
        # Get rid of any old bisect state
        #
-       rm -f "$GIT_DIR/refs/heads/bisect"
-       rm -rf "$GIT_DIR/refs/bisect/"
+       bisect_clean_state
        mkdir "$GIT_DIR/refs/bisect"
+
+       #
+       # Check for one bad and then some good revisions.
+       #
+       has_double_dash=0
+       for arg; do
+           case "$arg" in --) has_double_dash=1; break ;; esac
+       done
+       orig_args=$(sq "$@")
+       bad_seen=0
+       while [ $# -gt 0 ]; do
+           arg="$1"
+           case "$arg" in
+           --)
+               shift
+               break
+               ;;
+           *)
+               rev=$(git-rev-parse --verify "$arg^{commit}" 2>/dev/null) || {
+                   test $has_double_dash -eq 1 &&
+                       die "'$arg' does not appear to be a valid revision"
+                   break
+               }
+               if [ $bad_seen -eq 0 ]; then
+                   bad_seen=1
+                   bisect_write_bad "$rev"
+               else
+                   bisect_write_good "$rev"
+               fi
+               shift
+               ;;
+           esac
+        done
+
+       sq "$@" >"$GIT_DIR/BISECT_NAMES"
        {
            printf "git-bisect start"
-           sq "$@"
-       } >"$GIT_DIR/BISECT_LOG"
-       sq "$@" >"$GIT_DIR/BISECT_NAMES"
+           echo "$orig_args"
+       } >>"$GIT_DIR/BISECT_LOG"
+       bisect_auto_next
 }
 
 bisect_bad() {
@@ -90,12 +133,17 @@ bisect_bad() {
        *)
                usage ;;
        esac || exit
-       echo "$rev" >"$GIT_DIR/refs/bisect/bad"
-       echo "# bad: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
+       bisect_write_bad "$rev"
        echo "git-bisect bad $rev" >>"$GIT_DIR/BISECT_LOG"
        bisect_auto_next
 }
 
+bisect_write_bad() {
+       rev="$1"
+       echo "$rev" >"$GIT_DIR/refs/bisect/bad"
+       echo "# bad: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
+}
+
 bisect_good() {
        bisect_autostart
         case "$#" in
@@ -106,13 +154,19 @@ bisect_good() {
        for rev in $revs
        do
                rev=$(git-rev-parse --verify "$rev^{commit}") || exit
-               echo "$rev" >"$GIT_DIR/refs/bisect/good-$rev"
-               echo "# good: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
+               bisect_write_good "$rev"
                echo "git-bisect good $rev" >>"$GIT_DIR/BISECT_LOG"
+
        done
        bisect_auto_next
 }
 
+bisect_write_good() {
+       rev="$1"
+       echo "$rev" >"$GIT_DIR/refs/bisect/good-$rev"
+       echo "# good: "$(git-show-branch $rev) >>"$GIT_DIR/BISECT_LOG"
+}
+
 bisect_next_check() {
        next_ok=no
         test -f "$GIT_DIR/refs/bisect/bad" &&
@@ -190,14 +244,19 @@ bisect_reset() {
            usage ;;
        esac
        if git checkout "$branch"; then
-               rm -fr "$GIT_DIR/refs/bisect"
-               rm -f "$GIT_DIR/refs/heads/bisect" "$GIT_DIR/head-name"
-               rm -f "$GIT_DIR/BISECT_LOG"
-               rm -f "$GIT_DIR/BISECT_NAMES"
-               rm -f "$GIT_DIR/BISECT_RUN"
+               rm -f "$GIT_DIR/head-name"
+               bisect_clean_state
        fi
 }
 
+bisect_clean_state() {
+       rm -fr "$GIT_DIR/refs/bisect"
+       rm -f "$GIT_DIR/refs/heads/bisect"
+       rm -f "$GIT_DIR/BISECT_LOG"
+       rm -f "$GIT_DIR/BISECT_NAMES"
+       rm -f "$GIT_DIR/BISECT_RUN"
+}
+
 bisect_replay () {
        test -r "$1" || {
                echo >&2 "cannot read $1 for replaying"

diff --git a/t/t6030-bisect-run.sh b/t/t6030-bisect-run.sh
index 39c72283b516001ec110614a4f40dcdd2b06e90e..455dc60812ea43fad633c9006e5f67708dd099ee 100755 (executable)
--- a/t/t6030-bisect-run.sh
+++ b/t/t6030-bisect-run.sh
@@ -40,8 +40,8 @@ test_expect_success \
 # We want to automatically find the commit that
 # introduced "Another" into hello.
 test_expect_success \
-    'git bisect run simple case' \
-    'echo "#!/bin/sh" > test_script.sh &&
+    '"git bisect run" simple case' \
+    'echo "#"\!"/bin/sh" > test_script.sh &&
      echo "grep Another hello > /dev/null" >> test_script.sh &&
      echo "test \$? -ne 0" >> test_script.sh &&
      chmod +x test_script.sh &&
@@ -49,7 +49,21 @@ test_expect_success \
      git bisect good $HASH1 &&
      git bisect bad $HASH4 &&
      git bisect run ./test_script.sh > my_bisect_log.txt &&
-     grep "$HASH3 is first bad commit" my_bisect_log.txt'
+     grep "$HASH3 is first bad commit" my_bisect_log.txt &&
+     git bisect reset'
+
+# We want to automatically find the commit that
+# introduced "Ciao" into hello.
+test_expect_success \
+    '"git bisect run" with more complex "git bisect start"' \
+    'echo "#"\!"/bin/sh" > test_script.sh &&
+     echo "grep Ciao hello > /dev/null" >> test_script.sh &&
+     echo "test \$? -ne 0" >> test_script.sh &&
+     chmod +x test_script.sh &&
+     git bisect start $HASH4 $HASH1 &&
+     git bisect run ./test_script.sh > my_bisect_log.txt &&
+     grep "$HASH4 is first bad commit" my_bisect_log.txt &&
+     git bisect reset'
 
 #
 #