t3412: clean up GIT_EDITOR usage

a6c7a27 (rebase -i: correctly remember --root flag across --continue,
2009-01-26) introduced a more portable GIT_EDITOR usage, but left the
old tests unchanged.

Since we never use the editor (all tests run the rebase script as
proposed by rebase -i), just disable it outright, which simplifies the
tests.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t3412-rebase-root.sh

@@ -6,6 +6,10 @@ Tests if git rebase --root --onto <newparent> can rebase the root commit.
 '
 . ./test-lib.sh
 
+# we always run the interactive rebases unchanged, so just disable the editor
+GIT_EDITOR=:
+export GIT_EDITOR
+
 test_expect_success 'prepare repository' '
 	test_commit 1 A &&
 	test_commit 2 A &&
@@ -59,7 +63,7 @@ test_expect_success 'pre-rebase got correct input (2)' '
 
 test_expect_success 'rebase -i --root --onto <newbase>' '
 	git checkout -b work3 other &&
-	GIT_EDITOR=: git rebase -i --root --onto master &&
+	git rebase -i --root --onto master &&
 	git log --pretty=tformat:"%s" > rebased3 &&
 	test_cmp expect rebased3
 '
@@ -70,7 +74,7 @@ test_expect_success 'pre-rebase got correct input (3)' '
 
 test_expect_success 'rebase -i --root --onto <newbase> <branch>' '
 	git branch work4 other &&
-	GIT_EDITOR=: git rebase -i --root --onto master work4 &&
+	git rebase -i --root --onto master work4 &&
 	git log --pretty=tformat:"%s" > rebased4 &&
 	test_cmp expect rebased4
 '
@@ -81,7 +85,7 @@ test_expect_success 'pre-rebase got correct input (4)' '
 
 test_expect_success 'rebase -i -p with linear history' '
 	git checkout -b work5 other &&
-	GIT_EDITOR=: git rebase -i -p --root --onto master &&
+	git rebase -i -p --root --onto master &&
 	git log --pretty=tformat:"%s" > rebased5 &&
 	test_cmp expect rebased5
 '
@@ -111,7 +115,7 @@ EOF
 
 test_expect_success 'rebase -i -p with merge' '
 	git checkout -b work6 other &&
-	GIT_EDITOR=: git rebase -i -p --root --onto master &&
+	git rebase -i -p --root --onto master &&
 	git log --graph --topo-order --pretty=tformat:"%s" > rebased6 &&
 	test_cmp expect-side rebased6
 '
@@ -142,7 +146,7 @@ EOF
 
 test_expect_success 'rebase -i -p with two roots' '
 	git checkout -b work7 other &&
-	GIT_EDITOR=: git rebase -i -p --root --onto master &&
+	git rebase -i -p --root --onto master &&
 	git log --graph --topo-order --pretty=tformat:"%s" > rebased7 &&
 	test_cmp expect-third rebased7
 '
@@ -158,22 +162,14 @@ EOF
 
 test_expect_success 'pre-rebase hook stops rebase' '
 	git checkout -b stops1 other &&
-	(
-		GIT_EDITOR=:
-		export GIT_EDITOR
-		test_must_fail git rebase --root --onto master
-	) &&
+	test_must_fail git rebase --root --onto master &&
 	test "z$(git symbolic-ref HEAD)" = zrefs/heads/stops1
 	test 0 = $(git rev-list other...stops1 | wc -l)
 '
 
 test_expect_success 'pre-rebase hook stops rebase -i' '
 	git checkout -b stops2 other &&
-	(
-		GIT_EDITOR=:
-		export GIT_EDITOR
-		test_must_fail git rebase --root --onto master
-	) &&
+	test_must_fail git rebase --root --onto master &&
 	test "z$(git symbolic-ref HEAD)" = zrefs/heads/stops2
 	test 0 = $(git rev-list other...stops2 | wc -l)
 '
@@ -218,11 +214,7 @@ test_expect_success 'rebase --root with conflict (second part)' '
 
 test_expect_success 'rebase -i --root with conflict (first part)' '
 	git checkout -b conflict2 other &&
-	(
-		GIT_EDITOR=:
-		export GIT_EDITOR
-		test_must_fail git rebase -i --root --onto master
-	) &&
+	test_must_fail git rebase -i --root --onto master &&
 	git ls-files -u | grep "B$"
 '
 
@@ -260,11 +252,7 @@ EOF
 
 test_expect_success 'rebase -i -p --root with conflict (first part)' '
 	git checkout -b conflict3 other &&
-	(
-		GIT_EDITOR=:
-		export GIT_EDITOR
-		test_must_fail git rebase -i -p --root --onto master
-	) &&
+	test_must_fail git rebase -i -p --root --onto master &&
 	git ls-files -u | grep "B$"
 '