fix(pager): handle consecutive newlines properly (#27913)

2 files changed, 16 insertions, 9 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index e4ee254193..f5f9c4f77b 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -8085,10 +8085,12 @@ void ex_echo(exarg_T *eap)
         // Call msg_start() after eval1(), evaluating the expression
         // may cause a message to appear.
         if (eap->cmdidx == CMD_echo) {
-          // Mark the saved text as finishing the line, so that what
-          // follows is displayed on a new line when scrolling back
-          // at the more prompt.
-          msg_sb_eol();
+          if (!msg_didout) {
+            // Mark the saved text as finishing the line, so that what
+            // follows is displayed on a new line when scrolling back
+            // at the more prompt.
+            msg_sb_eol();
+          }
           msg_start();
         }
       } else if (eap->cmdidx == CMD_echo) {
diff --git a/src/nvim/message.c b/src/nvim/message.c
index 2725ad02c6..5a47908eb6 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -1191,7 +1191,7 @@ void wait_return(int redraw)
       check_timestamps(false);
     }
 
-    hit_return_msg();
+    hit_return_msg(true);
 
     do {
       // Remember "got_int", if it is set vgetc() probably returns a
@@ -1240,7 +1240,7 @@ void wait_return(int redraw)
             got_int = false;
           } else if (c != K_IGNORE) {
             c = K_IGNORE;
-            hit_return_msg();
+            hit_return_msg(false);
           }
         } else if (msg_scrolled > Rows - 2
                    && (c == 'j' || c == 'd' || c == 'f'
@@ -1313,14 +1313,19 @@ void wait_return(int redraw)
 }
 
 /// Write the hit-return prompt.
-static void hit_return_msg(void)
+///
+/// @param newline_sb  if starting a new line, add it to the scrollback.
+static void hit_return_msg(bool newline_sb)
 {
   int save_p_more = p_more;
 
-  p_more = false;       // don't want to see this message when scrolling back
+  if (!newline_sb) {
+    p_more = false;
+  }
   if (msg_didout) {     // start on a new line
     msg_putchar('\n');
   }
+  p_more = false;       // don't want to see this message when scrolling back
   msg_ext_set_kind("return_prompt");
   if (got_int) {
     msg_puts(_("Interrupt: "));
@@ -2968,7 +2973,7 @@ void repeat_message(void)
       msg_col = 0;
       msg_clr_eos();
     }
-    hit_return_msg();
+    hit_return_msg(false);
     msg_row = Rows - 1;
   }
 }