diff --git a/t/t3400-rebase.sh b/t/t3400-rebase.sh
index 71fd6396cd..0a491f2363 100755
--- a/t/t3400-rebase.sh
+++ b/t/t3400-rebase.sh
@@ -183,19 +183,19 @@ test_expect_success 'default to common base in @{upstream}s reflog if no upstrea
 	test_cmp expect actual
 '
 
-test_expect_success 'default to common base in @{upstream}s reflog if no upstream arg' '
+test_expect_success 'default to common base in @{upstream}s reflog if no upstream arg (--am)' '
 	git checkout -B default-base master &&
 	git checkout -B default topic &&
 	git config branch.default.remote . &&
 	git config branch.default.merge refs/heads/default-base &&
-	git rebase &&
+	git rebase --am &&
 	git rev-parse --verify default-base >expect &&
 	git rev-parse default~1 >actual &&
 	test_cmp expect actual &&
 	git checkout default-base &&
 	git reset --hard HEAD^ &&
 	git checkout default &&
-	git rebase &&
+	git rebase --am &&
 	git rev-parse --verify default-base >expect &&
 	git rev-parse default~1 >actual &&
 	test_cmp expect actual
@@ -226,7 +226,7 @@ test_expect_success 'cherry-picked commits and fork-point work together' '
 
 test_expect_success 'rebase --am -q is quiet' '
 	git checkout -b quiet topic &&
-	git rebase -q master >output.out 2>&1 &&
+	git rebase --am -q master >output.out 2>&1 &&
 	test_must_be_empty output.out
 '
 
@@ -325,7 +325,7 @@ test_expect_success 'rebase --am and --show-current-patch' '
 		echo two >>init.t &&
 		git commit -a -m two &&
 		git tag two &&
-		test_must_fail git rebase -f --onto init HEAD^ &&
+		test_must_fail git rebase --am -f --onto init HEAD^ &&
 		GIT_TRACE=1 git rebase --show-current-patch >/dev/null 2>stderr &&
 		grep "show.*$(git rev-parse two)" stderr
 	)
diff --git a/t/t3401-rebase-and-am-rename.sh b/t/t3401-rebase-and-am-rename.sh
index a0b9438b22..50803958fd 100755
--- a/t/t3401-rebase-and-am-rename.sh
+++ b/t/t3401-rebase-and-am-rename.sh
@@ -52,13 +52,13 @@ test_expect_success 'rebase --interactive: directory rename detected' '
 	)
 '
 
-test_expect_failure 'rebase (am): directory rename detected' '
+test_expect_failure 'rebase --am: directory rename detected' '
 	(
 		cd dir-rename &&
 
 		git checkout B^0 &&
 
-		git -c merge.directoryRenames=true rebase A &&
+		git -c merge.directoryRenames=true rebase --am A &&
 
 		git ls-files -s >out &&
 		test_line_count = 5 out &&
diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index a31583eb2f..f964b2cd41 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -1138,7 +1138,7 @@ test_expect_success C_LOCALE_OUTPUT 'rebase --edit-todo does not work on non-int
 	git checkout conflict-branch &&
 	(
 		set_fake_editor &&
-		test_must_fail git rebase -f --onto HEAD~2 HEAD~ &&
+		test_must_fail git rebase -f --am --onto HEAD~2 HEAD~ &&
 		test_must_fail git rebase --edit-todo
 	) &&
 	git rebase --abort
diff --git a/t/t3406-rebase-message.sh b/t/t3406-rebase-message.sh
index 0c2c569f95..7ce617fc1f 100755
--- a/t/t3406-rebase-message.sh
+++ b/t/t3406-rebase-message.sh
@@ -23,24 +23,24 @@ test_expect_success 'rebase -m' '
 '
 
 test_expect_success 'rebase against master twice' '
-	git rebase master >out &&
+	git rebase --am master >out &&
 	test_i18ngrep "Current branch topic is up to date" out
 '
 
 test_expect_success 'rebase against master twice with --force' '
-	git rebase --force-rebase master >out &&
+	git rebase --force-rebase --am master >out &&
 	test_i18ngrep "Current branch topic is up to date, rebase forced" out
 '
 
 test_expect_success 'rebase against master twice from another branch' '
 	git checkout topic^ &&
-	git rebase master topic >out &&
+	git rebase --am master topic >out &&
 	test_i18ngrep "Current branch topic is up to date" out
 '
 
 test_expect_success 'rebase fast-forward to master' '
 	git checkout topic^ &&
-	git rebase topic >out &&
+	git rebase --am topic >out &&
 	test_i18ngrep "Fast-forwarded HEAD to topic" out
 '
 
@@ -89,7 +89,7 @@ test_expect_success 'GIT_REFLOG_ACTION' '
 	git checkout -b reflog-topic start &&
 	test_commit reflog-to-rebase &&
 
-	git rebase reflog-onto &&
+	git rebase --am reflog-onto &&
 	git log -g --format=%gs -3 >actual &&
 	cat >expect <<-\EOF &&
 	rebase finished: returning to refs/heads/reflog-topic
@@ -99,7 +99,7 @@ test_expect_success 'GIT_REFLOG_ACTION' '
 	test_cmp expect actual &&
 
 	git checkout -b reflog-prefix reflog-to-rebase &&
-	GIT_REFLOG_ACTION=change-the-reflog git rebase reflog-onto &&
+	GIT_REFLOG_ACTION=change-the-reflog git rebase --am reflog-onto &&
 	git log -g --format=%gs -3 >actual &&
 	cat >expect <<-\EOF &&
 	rebase finished: returning to refs/heads/reflog-prefix
diff --git a/t/t3407-rebase-abort.sh b/t/t3407-rebase-abort.sh
index 910f218284..3e31826170 100755
--- a/t/t3407-rebase-abort.sh
+++ b/t/t3407-rebase-abort.sh
@@ -96,14 +96,14 @@ testrebase() {
 	'
 }
 
-testrebase "" .git/rebase-apply
+testrebase " --am" .git/rebase-apply
 testrebase " --merge" .git/rebase-merge
 
-test_expect_success 'rebase --quit' '
+test_expect_success 'rebase --am --quit' '
 	cd "$work_dir" &&
 	# Clean up the state from the previous one
 	git reset --hard pre-rebase &&
-	test_must_fail git rebase master &&
+	test_must_fail git rebase --am master &&
 	test_path_is_dir .git/rebase-apply &&
 	head_before=$(git rev-parse HEAD) &&
 	git rebase --quit &&
diff --git a/t/t3420-rebase-autostash.sh b/t/t3420-rebase-autostash.sh
index 5f7e73cf83..3816159e20 100755
--- a/t/t3420-rebase-autostash.sh
+++ b/t/t3420-rebase-autostash.sh
@@ -234,7 +234,7 @@ test_expect_success "rebase: noop rebase" '
 	git checkout feature-branch
 '
 
-testrebase "" .git/rebase-apply
+testrebase " --am" .git/rebase-apply
 testrebase " --merge" .git/rebase-merge
 testrebase " --interactive" .git/rebase-merge
 
diff --git a/t/t3421-rebase-topology-linear.sh b/t/t3421-rebase-topology-linear.sh
index 57334dca7e..e12304012a 100755
--- a/t/t3421-rebase-topology-linear.sh
+++ b/t/t3421-rebase-topology-linear.sh
@@ -26,7 +26,7 @@ test_run_rebase () {
 		test_linear_range 'd e' c..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -50,7 +50,7 @@ test_run_rebase () {
 		test_cmp_rev e HEAD
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -66,7 +66,7 @@ test_run_rebase () {
 		test_linear_range 'd e' b..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success --fork-point
 test_run_rebase success -m
 test_run_rebase success -i
@@ -83,7 +83,7 @@ test_run_rebase () {
 		test_linear_range 'd e' branch-b..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success --fork-point
 test_run_rebase success -m
 test_run_rebase success -i
@@ -98,7 +98,7 @@ test_run_rebase () {
 		test_cmp_rev e HEAD
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success --fork-point
 test_run_rebase success -m
 test_run_rebase success -i
@@ -139,7 +139,7 @@ test_run_rebase () {
 		test_linear_range 'd i' h..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -154,7 +154,7 @@ test_run_rebase () {
 		test_linear_range 'd' h..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -169,7 +169,7 @@ test_run_rebase () {
 		test_linear_range 'd i' f..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -184,7 +184,7 @@ test_run_rebase () {
 		test_linear_range 'd gp i' h..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -212,7 +212,7 @@ test_run_rebase () {
 		test_linear_range 'j d k l' c..
 	"
 }
-test_run_rebase failure ''
+test_run_rebase failure --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase failure -p
@@ -227,7 +227,7 @@ test_run_rebase () {
 		test_linear_range 'd k l' c..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -242,7 +242,7 @@ test_run_rebase () {
 		test_linear_range 'd k l' j..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -282,7 +282,7 @@ test_run_rebase () {
 		test_linear_range 'x y' c..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -297,7 +297,7 @@ test_run_rebase () {
 		test_linear_range 'x y' c..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase failure -p
@@ -312,7 +312,7 @@ test_run_rebase () {
 		test_linear_range 'x y' m..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase success -p
@@ -328,7 +328,7 @@ test_run_rebase () {
 	"
 }
 
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase failure -p
@@ -343,7 +343,7 @@ test_run_rebase () {
 		test_linear_range 'x y' m..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 test_have_prereq !REBASE_P || test_run_rebase failure -p
diff --git a/t/t3425-rebase-topology-merges.sh b/t/t3425-rebase-topology-merges.sh
index fd8efe84fe..19700b025b 100755
--- a/t/t3425-rebase-topology-merges.sh
+++ b/t/t3425-rebase-topology-merges.sh
@@ -54,7 +54,7 @@ test_run_rebase () {
 		test_linear_range 'n o' e..
 	"
 }
-test_run_rebase success ''
+test_run_rebase success --am
 test_run_rebase success -m
 test_run_rebase success -i
 
@@ -70,7 +70,7 @@ test_run_rebase () {
 		test_linear_range "\'"$expected"\'" d..
 	"
 }
-test_run_rebase success 'n o e' ''
+test_run_rebase success 'n o e' --am
 test_run_rebase success 'n o e' -m
 test_run_rebase success 'n o e' -i
 
@@ -86,7 +86,7 @@ test_run_rebase () {
 		test_linear_range "\'"$expected"\'" c..
 	"
 }
-test_run_rebase success 'd n o e' ''
+test_run_rebase success 'd n o e' --am
 test_run_rebase success 'd n o e' -m
 test_run_rebase success 'd n o e' -i
 
@@ -102,7 +102,7 @@ test_run_rebase () {
 		test_linear_range "\'"$expected"\'" c..
 	"
 }
-test_run_rebase success 'd n o e' ''
+test_run_rebase success 'd n o e' --am
 test_run_rebase success 'd n o e' -m
 test_run_rebase success 'd n o e' -i
 
diff --git a/t/t3432-rebase-fast-forward.sh b/t/t3432-rebase-fast-forward.sh
index 40388ccf9f..4b3cecce56 100755
--- a/t/t3432-rebase-fast-forward.sh
+++ b/t/t3432-rebase-fast-forward.sh
@@ -28,8 +28,8 @@ test_rebase_same_head () {
 	shift &&
 	cmp_f="$1" &&
 	shift &&
-	test_rebase_same_head_ $status_n $what_n $cmp_n "" "$*" &&
-	test_rebase_same_head_ $status_f $what_f $cmp_f " --no-ff" "$*"
+	test_rebase_same_head_ $status_n $what_n $cmp_n " --am" "$*" &&
+	test_rebase_same_head_ $status_f $what_f $cmp_f " --am --no-ff" "$*"
 	test_rebase_same_head_ $status_n $what_n $cmp_n " --merge" "$*" &&
 	test_rebase_same_head_ $status_f $what_f $cmp_f " --merge --no-ff" "$*"
 }
diff --git a/t/t5407-post-rewrite-hook.sh b/t/t5407-post-rewrite-hook.sh
index 7344253bfb..a8a73616e4 100755
--- a/t/t5407-post-rewrite-hook.sh
+++ b/t/t5407-post-rewrite-hook.sh
@@ -53,10 +53,10 @@ test_expect_success 'git commit --amend --no-post-rewrite' '
 	test ! -f post-rewrite.data
 '
 
-test_expect_success 'git rebase' '
+test_expect_success 'git rebase --am' '
 	git reset --hard D &&
 	clear_hook_input &&
-	test_must_fail git rebase --onto A B &&
+	test_must_fail git rebase --am --onto A B &&
 	echo C > foo &&
 	git add foo &&
 	git rebase --continue &&
@@ -68,10 +68,10 @@ test_expect_success 'git rebase' '
 	verify_hook_input
 '
 
-test_expect_success 'git rebase --skip' '
+test_expect_success 'git rebase --am --skip' '
 	git reset --hard D &&
 	clear_hook_input &&
-	test_must_fail git rebase --onto A B &&
+	test_must_fail git rebase --am --onto A B &&
 	test_must_fail git rebase --skip &&
 	echo D > foo &&
 	git add foo &&
@@ -84,10 +84,10 @@ test_expect_success 'git rebase --skip' '
 	verify_hook_input
 '
 
-test_expect_success 'git rebase --skip the last one' '
+test_expect_success 'git rebase --am --skip the last one' '
 	git reset --hard F &&
 	clear_hook_input &&
-	test_must_fail git rebase --onto D A &&
+	test_must_fail git rebase --am --onto D A &&
 	git rebase --skip &&
 	echo rebase >expected.args &&
 	cat >expected.data <<-EOF &&
diff --git a/t/t7512-status-help.sh b/t/t7512-status-help.sh
index 66d7a62797..d22b0acf2a 100755
--- a/t/t7512-status-help.sh
+++ b/t/t7512-status-help.sh
@@ -71,10 +71,10 @@ test_expect_success 'prepare for rebase conflicts' '
 '
 
 
-test_expect_success 'status when rebase in progress before resolving conflicts' '
+test_expect_success 'status when rebase --am in progress before resolving conflicts' '
 	test_when_finished "git rebase --abort" &&
 	ONTO=$(git rev-parse --short HEAD^^) &&
-	test_must_fail git rebase HEAD^ --onto HEAD^^ &&
+	test_must_fail git rebase --am HEAD^ --onto HEAD^^ &&
 	cat >expected <<EOF &&
 rebase in progress; onto $ONTO
 You are currently rebasing branch '\''rebase_conflicts'\'' on '\''$ONTO'\''.
@@ -94,11 +94,11 @@ EOF
 '
 
 
-test_expect_success 'status when rebase in progress before rebase --continue' '
+test_expect_success 'status when rebase --am in progress before rebase --continue' '
 	git reset --hard rebase_conflicts &&
 	test_when_finished "git rebase --abort" &&
 	ONTO=$(git rev-parse --short HEAD^^) &&
-	test_must_fail git rebase HEAD^ --onto HEAD^^ &&
+	test_must_fail git rebase --am HEAD^ --onto HEAD^^ &&
 	echo three >main.txt &&
 	git add main.txt &&
 	cat >expected <<EOF &&
@@ -688,7 +688,7 @@ EOF
 '
 
 
-test_expect_success 'status when rebase conflicts with statushints disabled' '
+test_expect_success 'status when rebase --am conflicts with statushints disabled' '
 	git reset --hard master &&
 	git checkout -b statushints_disabled &&
 	test_when_finished "git config --local advice.statushints true" &&
@@ -698,7 +698,7 @@ test_expect_success 'status when rebase conflicts with statushints disabled' '
 	test_commit three_statushints main.txt three &&
 	test_when_finished "git rebase --abort" &&
 	ONTO=$(git rev-parse --short HEAD^^) &&
-	test_must_fail git rebase HEAD^ --onto HEAD^^ &&
+	test_must_fail git rebase --am HEAD^ --onto HEAD^^ &&
 	cat >expected <<EOF &&
 rebase in progress; onto $ONTO
 You are currently rebasing branch '\''statushints_disabled'\'' on '\''$ONTO'\''.