API: buf_get_lines, buf_line_count handle unloaded buffers #7688

src/nvim/api/buffer.c

@@ -45,6 +45,11 @@ Integer nvim_buf_line_count(Buffer buffer, Error *err)
     return 0;
   }
 
+  // return sentinel value if the buffer isn't loaded
+  if (buf->b_ml.ml_mfp == NULL) {
+    return 0;
+  }
+
   return buf->b_ml.ml_line_count;
 }
 
@@ -221,6 +226,11 @@ ArrayOf(String) nvim_buf_get_lines(uint64_t channel_id,
     return rv;
   }
 
+  // return sentinel value if the buffer isn't loaded
+  if (buf->b_ml.ml_mfp == NULL) {
+    return rv;
+  }
+
   bool oob = false;
   start = normalize_index(buf, start, &oob);
   end = normalize_index(buf, end, &oob);