reopen_tempfile(): truncate opened file

diff --git a/t/t2020-checkout-detach.sh b/t/t2020-checkout-detach.sh
index bb4f2e0c631f1de7421f50b9fa64f11276fe9645..1fa670625c5be87294eec9c5fe86bf2defff2ce2 100755 (executable)
--- a/t/t2020-checkout-detach.sh
+++ b/t/t2020-checkout-detach.sh
@@ -189,8 +189,12 @@ test_expect_success 'no advice given for explicit detached head state' '
 # Detached HEAD tests for GIT_PRINT_SHA1_ELLIPSIS (new format)
 test_expect_success 'describe_detached_head prints no SHA-1 ellipsis when not asked to' "
 
+       commit=$(git rev-parse --short=12 master^) &&
+       commit2=$(git rev-parse --short=12 master~2) &&
+       commit3=$(git rev-parse --short=12 master~3) &&
+
        # The first detach operation is more chatty than the following ones.
-       cat >1st_detach <<-'EOF' &&
+       cat >1st_detach <<-EOF &&
        Note: checking out 'HEAD^'.
 
        You are in 'detached HEAD' state. You can look around, make experimental
@@ -202,18 +206,18 @@ test_expect_success 'describe_detached_head prints no SHA-1 ellipsis when not as
 
          git checkout -b <new-branch-name>
 
-       HEAD is now at 7c7cd714e262 three
+       HEAD is now at \$commit three
        EOF
 
        # The remaining ones just show info about previous and current HEADs.
-       cat >2nd_detach <<-'EOF' &&
-       Previous HEAD position was 7c7cd714e262 three
-       HEAD is now at 139b20d8e6c5 two
+       cat >2nd_detach <<-EOF &&
+       Previous HEAD position was \$commit three
+       HEAD is now at \$commit2 two
        EOF
 
-       cat >3rd_detach <<-'EOF' &&
-       Previous HEAD position was 139b20d8e6c5 two
-       HEAD is now at d79ce1670bdc one
+       cat >3rd_detach <<-EOF &&
+       Previous HEAD position was \$commit2 two
+       HEAD is now at \$commit3 one
        EOF
 
        reset &&
@@ -261,8 +265,12 @@ test_expect_success 'describe_detached_head prints no SHA-1 ellipsis when not as
 # Detached HEAD tests for GIT_PRINT_SHA1_ELLIPSIS (old format)
 test_expect_success 'describe_detached_head does print SHA-1 ellipsis when asked to' "
 
+       commit=$(git rev-parse --short=12 master^) &&
+       commit2=$(git rev-parse --short=12 master~2) &&
+       commit3=$(git rev-parse --short=12 master~3) &&
+
        # The first detach operation is more chatty than the following ones.
-       cat >1st_detach <<-'EOF' &&
+       cat >1st_detach <<-EOF &&
        Note: checking out 'HEAD^'.
 
        You are in 'detached HEAD' state. You can look around, make experimental
@@ -274,18 +282,18 @@ test_expect_success 'describe_detached_head does print SHA-1 ellipsis when asked
 
          git checkout -b <new-branch-name>
 
-       HEAD is now at 7c7cd714e262... three
+       HEAD is now at \$commit... three
        EOF
 
        # The remaining ones just show info about previous and current HEADs.
-       cat >2nd_detach <<-'EOF' &&
-       Previous HEAD position was 7c7cd714e262... three
-       HEAD is now at 139b20d8e6c5... two
+       cat >2nd_detach <<-EOF &&
+       Previous HEAD position was \$commit... three
+       HEAD is now at \$commit2... two
        EOF
 
-       cat >3rd_detach <<-'EOF' &&
-       Previous HEAD position was 139b20d8e6c5... two
-       HEAD is now at d79ce1670bdc... one
+       cat >3rd_detach <<-EOF &&
+       Previous HEAD position was \$commit2... two
+       HEAD is now at \$commit3... one
        EOF
 
        reset &&