log-tree: respect diffopt's configured output file stream

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 79afa8748eec6c8a9dece4db58c6efcfb343f2ae..0055ebba46d539f30b9484335501571c3b4879bd 100644 (file)
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -322,6 +322,19 @@ else
        exec 4>/dev/null 3>/dev/null
 fi
 
+# Send any "-x" output directly to stderr to avoid polluting tests
+# which capture stderr. We can do this unconditionally since it
+# has no effect if tracing isn't turned on.
+#
+# Note that this sets up the trace fd as soon as we assign the variable, so it
+# must come after the creation of descriptor 4 above. Likewise, we must never
+# unset this, as it has the side effect of closing descriptor 4, which we
+# use to show verbose tests to the user.
+#
+# Note also that we don't need or want to export it. The tracing is local to
+# this shell, and we would not want to influence any shells we exec.
+BASH_XTRACEFD=4
+
 test_failure=0
 test_count=0
 test_fixed=0
@@ -854,10 +867,10 @@ test -d "$GIT_BUILD_DIR"/templates/blt || {
        error "You haven't built things yet, have you?"
 }
 
-if ! test -x "$GIT_BUILD_DIR"/test-chmtime
+if ! test -x "$GIT_BUILD_DIR"/t/helper/test-chmtime
 then
        echo >&2 'You need to build test-chmtime:'
-       echo >&2 'Run "make test-chmtime" in the source (toplevel) directory'
+       echo >&2 'Run "make t/helper/test-chmtime" in the source (toplevel) directory'
        exit 1
 fi