Fix --separate flag

src/sed/processor.rs

@@ -695,9 +695,13 @@ pub fn process_all_files(
             .map_err_context(|| format!("error opening input file {}", path.quote()))?;
         let output = in_place.begin(path)?;
 
-        if index == 0 || context.separate {
+        if context.separate || index == 0 {
             context.line_number = 0;
             reset_latched_address_ranges(&mut context.range_commands);
+
+            // Reset hold space for separate file processing
+            context.hold.content.clear();
+            context.hold.has_newline = true;
         }
 
         context.input_name = path.quote().to_string();

tests/by-util/test_sed.rs

@@ -380,6 +380,10 @@ check_output!(
     pattern_hold_append_swap,
     ["-e", r"2h;3H;4g;5G;6x;6p;6x;6p", LINES1]
 );
+check_output!(
+    pattern_swap_separate,
+    ["--separate", r"4x;6x", LINES1, LINES2]
+);
 check_output!(pattern_next_output, ["-e", r"4n", LINES1]);
 check_output!(pattern_next_no_output, ["-n", "-e", r"4n", LINES1]);
 check_output!(pattern_next_print_output, ["-e", r"4n;p", LINES1]);

tests/fixtures/sed/output/pattern_swap_separate

@@ -0,0 +1,23 @@
+l1_1
+l1_2
+l1_3
+
+l1_5
+l1_4
+l1_7
+l1_8
+l1_9
+l1_10
+l1_11
+l1_12
+l1_13
+l1_14
+l2_1
+l2_2
+l2_3
+
+l2_5
+l2_4
+l2_7
+l2_8
+l2_9