Merge branch 'ctest-and-windows'

This is a backport of the patches that made it into core Git via
246eedf (Merge branch 'js/cmake-updates', 2022-10-27).

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

t/test-lib.sh

@@ -51,7 +51,16 @@ then
 	TEST_OUTPUT_DIRECTORY=$TEST_DIRECTORY
 fi
 GIT_BUILD_DIR="${TEST_DIRECTORY%/t}"
-if test "$TEST_DIRECTORY" = "$GIT_BUILD_DIR"
+if test -f "$GIT_BUILD_DIR/GIT-BUILD-DIR"
+then
+	GIT_BUILD_DIR="$(cat "$GIT_BUILD_DIR/GIT-BUILD-DIR")" || exit 1
+	# On Windows, we must convert Windows paths lest they contain a colon
+	case "$(uname -s)" in
+	*MINGW*)
+		GIT_BUILD_DIR="$(cygpath -au "$GIT_BUILD_DIR")"
+		;;
+	esac
+elif test "$TEST_DIRECTORY" = "$GIT_BUILD_DIR"
 then
 	echo "PANIC: Running in a $TEST_DIRECTORY that doesn't end in '/t'?" >&2
 	exit 1