Add a test for the processing order when generating a tags file

tests/ctags/Makefile.am

@@ -319,3 +319,13 @@ TAGS_LOG_COMPILER = $(srcdir)/runner.sh
 
 TESTS = $(test_results)
 EXTRA_DIST = $(test_sources) $(test_results)
+
+# check processing order of files on the command line
+check_processing_order_sources = \
+	process_order.c.tags process_order_1.h process_order_2.h
+EXTRA_DIST += $(check_processing_order_sources)
+.PHONY: check-processing-order
+check-processing-order: $(check_processing_order_sources)
+	srcdir="$(srcdir)" top_builddir="$(top_builddir)" \
+	$(srcdir)/runner.sh --result $(check_processing_order_sources:%=$(srcdir)/%)
+check-local: check-processing-order

tests/ctags/process_order.c.tags

+# format=tagmanager
+I1_E14anon_enum_00
+I1_E24anon_enum_00
+I2_E14anon_enum_10
+I2_E24anon_enum_10
+anon_enum_020
+anon_enum_120

tests/ctags/process_order_1.h

+enum {
+	I1_E1,
+	I1_E2,
+};

tests/ctags/process_order_2.h

+enum {
+	I2_E1,
+	I2_E2,
+};

tests/ctags/runner.sh

@@ -17,9 +17,21 @@ mkdir -p "$CONFDIR/filedefs/" || exit 99
 cp "${srcdir:-.}"/../../data/filetype_extensions.conf "$CONFDIR" || exit 99
 cp "${srcdir:-.}"/../../data/filedefs/filetypes.* "$CONFDIR/filedefs/" || exit 99
 
-result="$1"
-source="${result%.*}"
+if [ "$1" = "--result" ]; then
+  # --result $result $source...
+  [ $# -gt 2 ] || exit 99
+  shift
+  result="$1"
+  shift
+  source="$1"
+else
+  # result is $1 and source is inferred from result
+  result="$1"
+  source="${result%.*}"
+fi
+shift
+
 tagfile="$TMPDIR/test.${source##*.}.tags"
 
-"$GEANY" -c "$CONFDIR" -P -g "$tagfile" "$source" || exit 1
+"$GEANY" -c "$CONFDIR" -P -g "$tagfile" "$source" "$@" || exit 1
 diff -u "$result" "$tagfile" || exit 2