paste: edge-case: handle EOL at end-of-buffer

This is "readfile()-style", see also ":help channel-lines".

2 files changed, 15 insertions, 6 deletions

diff --git a/src/nvim/api/vim.c b/src/nvim/api/vim.c
index bafb21bd4e..9ba855b61f 100644
--- a/src/nvim/api/vim.c
+++ b/src/nvim/api/vim.c
@@ -1210,9 +1210,13 @@ Dictionary nvim_get_namespaces(void)
 ///
 /// Compare |:put| and |p| which are always linewise.
 ///
-/// @param lines contents
-/// @param type type ("c", "l", "b") or empty to guess from contents
-/// @param direction behave like |P| instead of |p|
+/// @param lines  |readfile()|-style list of lines. |channel-lines|
+/// @param type  Edit behavior:
+///              - "b" |blockwise-visual| mode
+///              - "c" |characterwise| mode
+///              - "l" |linewise| mode
+///              - ""  guess by contents
+/// @param direction  Behave like |P| instead of |p|
 /// @param[out] err Error details, if any
 void nvim_put(ArrayOf(String) lines, String type, Boolean direction,
               Error *err)
diff --git a/src/nvim/tui/input.c b/src/nvim/tui/input.c
index 79615e30da..8ee9640f9f 100644
--- a/src/nvim/tui/input.c
+++ b/src/nvim/tui/input.c
@@ -104,9 +104,9 @@ static Array string_to_array(const String input)
 {
   Array ret = ARRAY_DICT_INIT;
   for (size_t i = 0; i < input.size; i++) {
-    const char *const start = input.data + i;
-    const size_t line_len
-      = (size_t)((char *)xmemscan(start, NL, input.size - i) - start);
+    const char *start = input.data + i;
+    const char *end = xmemscan(start, NL, input.size - i);
+    const size_t line_len = (size_t)(end - start);
     i += line_len;
 
     String s = {
@@ -115,6 +115,11 @@ static Array string_to_array(const String input)
     };
     memchrsub(s.data, NUL, NL, line_len);
     ADD(ret, STRING_OBJ(s));
+    // If line ends at end-of-buffer, add empty final item.
+    // This is "readfile()-style", see also ":help channel-lines".
+    if (i + 1 == input.size && end[0] == NL) {
+      ADD(ret, STRING_OBJ(cchar_to_string(NUL)));
+    }
   }
 
   return ret;