Add line cleanup ANSI codes before printing progress bar info

- Rationale: To clean up possible leftovers from previous output in
 cases when separation lines was not enough to clean space for progress
 bar, over when playback start over in the loop after the end.
- Also got rid of trailing spaces after printing status.

Signed-off-by: Michael Orlov <michael.orlov@apex.ai>

rosbag2_transport/src/rosbag2_transport/player_progress_bar_impl.hpp

@@ -134,13 +134,12 @@ class PlayerProgressBarImpl {
     ss <<
         // Clear and print newlines
       progress_bar_helper_clear_and_move_cursor_down_ <<
-        // Print progress bar
-      "====== Playback Progress ======\n" <<
+      // Print progress bar
+      // Use "\033[2K" ANSI control code to clear an entire line in the terminal before output.
+      "\033[2K====== Playback Progress ======\n\033[2K" <<
       "[" << std::fixed << std::setprecision(9) << progress_current_time_secs_ <<
       "] Duration " << std::setprecision(2) << progress_secs_from_start_ <<
-        // Spaces at the end are used to clear any previous progress bar in case the new one is
-        // shorter, which can happen when the playback starts a new loop.
-      "/" << duration_secs_ << " [" << static_cast<char>(status) << "]      \n" <<
+      "/" << duration_secs_ << " [" << static_cast<char>(status) << "]\n" <<
         // Go up to the beginning of the blank lines
       progress_bar_helper_move_cursor_up_;
     o_stream_ << ss.rdbuf() << std::flush;

rosbag2_transport/test/rosbag2_transport/test_player_progress_bar.cpp

@@ -73,8 +73,8 @@ TEST_F(TestPlayerProgressBar, can_dtor_after_output) {
   }
   EXPECT_THAT(oss.str(),
     MatchesRegex(
-      "====== Playback Progress ======\n"
-      "\\[1000000000.000000000\\] Duration 0\\.00/1000000000\\.00 \\[D\\].*"
+      "\033\\[2K====== Playback Progress ======\n\033\\[2K"
+      "\\[1000000000.000000000\\] Duration 0\\.00/1000000000\\.00 \\[D\\]\n.*"
     )
   );
 }
@@ -124,10 +124,10 @@ TEST_F(TestPlayerProgressBar, update_status_with_enabled_progress_bar) {
     progress_bar->update(PlayerProgressBar::PlayerStatus::STOPPED);
     EXPECT_THAT(oss.str(),
       MatchesRegex(
-        ".*====== Playback Progress ======\n"
+        ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
         "\\[0\\.000000000\\] Duration 0\\.00/0\\.00 \\[R\\].*"
-        ".*====== Playback Progress ======\n"
-        "\\[0\\.000000000\\] Duration 0\\.00/0\\.00 \\[S\\].*"
+        ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
+        "\\[0\\.000000000\\] Duration 0\\.00/0\\.00 \\[S\\]\n.*"
       )
     );
   }
@@ -257,11 +257,11 @@ TEST_F(TestPlayerProgressBar, update_with_limited_rate_respect_update_rate) {
   // Check if the progress bar is updated at the correct 3 timestamps
   EXPECT_THAT(oss.str(),
     MatchesRegex(
-      ".*====== Playback Progress ======\n"
+      ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
       "\\[1\\.000000000\\] Duration 0\\.00/5\\.00"
-      ".*====== Playback Progress ======\n"
+      ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
       "\\[1\\.325000000\\] Duration 0\\.32/5\\.00"
-      ".*====== Playback Progress ======\n"
+      ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
       "\\[1\\.700000000\\] Duration 0\\.70/5\\.00.*"
     )
   );
@@ -317,7 +317,7 @@ TEST_F(TestPlayerProgressBar, update_with_limited_rate_with_zero_timestamp) {
 
   EXPECT_THAT(oss.str(),
     MatchesRegex(
-      ".*====== Playback Progress ======\n"
+      ".*\033\\[2K====== Playback Progress ======\n\033\\[2K"
       "\\[0\\.000000000\\] Duration -1\\.00/5\\.00.*"
     )
   );