clipboard: improve the handling of newlines in `get_clipboard`

This makes the interpretion consistent with the way newlines are used in
the VIMENC format, while keeping the same fallback behaviour when
regtype is unspecified. Also check both cases explicitly in the tests.

1 files changed, 18 insertions, 6 deletions

diff --git a/src/nvim/ops.c b/src/nvim/ops.c
index e73868a0fa..f0caaad97b 100644
--- a/src/nvim/ops.c
+++ b/src/nvim/ops.c
@@ -5360,10 +5360,13 @@ static void get_clipboard(int name, bool quiet)
       goto err;
     }
     char_u* regtype = res->lv_last->li_tv.vval.v_string;
-    if (regtype == NULL || strlen((char*)regtype) != 1) {
+    if (regtype == NULL || strlen((char*)regtype) > 1) {
       goto err;
     }
     switch (regtype[0]) {
+    case 0:
+      reg->y_type = MAUTO;
+      break;
     case 'v': case 'c':
       reg->y_type = MCHAR;
       break;
@@ -5393,15 +5396,23 @@ static void get_clipboard(int name, bool quiet)
     reg->y_array[i++] = (uint8_t *)xstrdup((char *)li->li_tv.vval.v_string);
   }
 
-  if (reg->y_type == MAUTO) {
-    if (reg->y_size > 0 && strlen((char*)reg->y_array[reg->y_size-1]) == 0) {
-      reg->y_type = MLINE;
+  if (reg->y_size > 0 && strlen((char*)reg->y_array[reg->y_size-1]) == 0) {
+    // a known-to-be charwise yank might have a final linebreak
+    // but otherwise there is no line after the final newline
+    if (reg->y_type != MCHAR) {
       free(reg->y_array[reg->y_size-1]);
       reg->y_size--;
-    } else {
+      if (reg->y_type == MAUTO) {
+        reg->y_type = MLINE;
+      }
+    }
+  } else {
+    if (reg->y_type == MAUTO) {
       reg->y_type = MCHAR;
     }
-  } else if (reg->y_type == MBLOCK) {
+  }
+
+  if (reg->y_type == MBLOCK) {
     int maxlen = 0;
     for (int i = 0; i < reg->y_size; i++) {
       int rowlen = STRLEN(reg->y_array[i]);
@@ -5453,6 +5464,7 @@ static void set_clipboard(int name)
     break;
   case MBLOCK:
     regtype = 'b';
+    list_append_string(lines, (char_u*)"", 0);
     break;
   }
   list_append_string(args, &regtype, 1);