1 files changed, 95 insertions, 4 deletions

diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index ac6c8c8aa6..c8b550f902 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -31,6 +31,7 @@
 #include "nvim/message.h"
 // TODO(ZyX-I): Move line_breakcheck out of misc1
 #include "nvim/misc1.h"  // For line_breakcheck
+#include "nvim/os/fileio.h"
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "eval/typval.c.generated.h"
@@ -45,6 +46,70 @@ bool tv_in_free_unref_items = false;
 const char *const tv_empty_string = "";
 
 //{{{1 Lists
+//{{{2 List log
+#ifdef LOG_LIST_ACTIONS
+ListLog *list_log_first = NULL;
+ListLog *list_log_last = NULL;
+
+/// Write list log to the given file
+///
+/// @param[in]  fname  File to write log to. Will be appended to if already
+///                    present.
+void list_write_log(const char *const fname)
+  FUNC_ATTR_NONNULL_ALL
+{
+  FileDescriptor fp;
+  const int fo_ret = file_open(&fp, fname, kFileCreate|kFileAppend, 0600);
+  if (fo_ret != 0) {
+    emsgf(_("E5142: Failed to open file %s: %s"), fname, os_strerror(fo_ret));
+    return;
+  }
+  for (ListLog *chunk = list_log_first; chunk != NULL;) {
+    for (size_t i = 0; i < chunk->size; i++) {
+      char buf[10 + 1 + ((16 + 3) * 3) + (8 + 2) + 2];
+      //       act  :     hex  " c:"      len "[]" "\n\0"
+      const ListLogEntry entry = chunk->entries[i];
+      const size_t snp_len = (size_t)snprintf(
+          buf, sizeof(buf),
+          "%-10.10s: l:%016" PRIxPTR "[%08d] 1:%016" PRIxPTR " 2:%016" PRIxPTR
+          "\n",
+          entry.action, entry.l, entry.len, entry.li1, entry.li2);
+      assert(snp_len + 1 == sizeof(buf));
+      const ptrdiff_t fw_ret = file_write(&fp, buf, snp_len);
+      if (fw_ret != (ptrdiff_t)snp_len) {
+        assert(fw_ret < 0);
+        if (i) {
+          memmove(chunk->entries, chunk->entries + i,
+                  sizeof(chunk->entries[0]) * (chunk->size - i));
+          chunk->size -= i;
+        }
+        emsgf(_("E5143: Failed to write to file %s: %s"),
+              fname, os_strerror((int)fw_ret));
+        return;
+      }
+    }
+    list_log_first = chunk->next;
+    xfree(chunk);
+    chunk = list_log_first;
+  }
+  const int fc_ret = file_close(&fp, true);
+  if (fc_ret != 0) {
+    emsgf(_("E5144: Failed to close file %s: %s"), fname, os_strerror(fc_ret));
+  }
+}
+
+#ifdef EXITFREE
+/// Free list log
+void list_free_log(void)
+{
+  for (ListLog *chunk = list_log_first; chunk != NULL;) {
+    list_log_first = chunk->next;
+    xfree(chunk);
+    chunk = list_log_first;
+  }
+}
+#endif
+#endif
 //{{{2 List item
 
 /// Allocate a list item
@@ -132,8 +197,14 @@ void tv_list_watch_fix(list_T *const l, const listitem_T *const item)
 ///
 /// Caller should take care of the reference count.
 ///
+/// @param[in]  len  Expected number of items to be populated before list
+///                  becomes accessible from VimL. It is still valid to
+///                  underpopulate a list, value only controls how many elements
+///                  will be allocated in advance. Currently does nothing.
+///                  @see ListLenSpecials.
+///
 /// @return [allocated] new list.
-list_T *tv_list_alloc(void)
+list_T *tv_list_alloc(const ptrdiff_t len)
   FUNC_ATTR_NONNULL_RET
 {
   list_T *const list = xcalloc(1, sizeof(list_T));
@@ -145,6 +216,7 @@ list_T *tv_list_alloc(void)
   list->lv_used_prev = NULL;
   list->lv_used_next = gc_first_list;
   gc_first_list = list;
+  list_log(list, NULL, (void *)(uintptr_t)len, "alloc");
   return list;
 }
 
@@ -174,6 +246,8 @@ void tv_list_init_static10(staticList10_T *const sl)
     li->li_prev = li - 1;
     li->li_next = li + 1;
   }
+  list_log((const list_T *)sl, &sl->sl_items[0], &sl->sl_items[SL_SIZE - 1],
+           "s10init");
 #undef SL_SIZE
 }
 
@@ -185,6 +259,7 @@ void tv_list_init_static(list_T *const l)
 {
   memset(l, 0, sizeof(*l));
   l->lv_refcount = DO_NOT_FREE_CNT;
+  list_log(l, NULL, NULL, "sinit");
 }
 
 /// Free items contained in a list
@@ -193,6 +268,7 @@ void tv_list_init_static(list_T *const l)
 void tv_list_free_contents(list_T *const l)
   FUNC_ATTR_NONNULL_ALL
 {
+  list_log(l, NULL, NULL, "freecont");
   for (listitem_T *item = l->lv_first; item != NULL; item = l->lv_first) {
     // Remove the item before deleting it.
     l->lv_first = item->li_next;
@@ -222,6 +298,7 @@ void tv_list_free_list(list_T *const l)
   if (l->lv_used_next != NULL) {
     l->lv_used_next->lv_used_prev = l->lv_used_prev;
   }
+  list_log(l, NULL, NULL, "freelist");
 
   xfree(l);
 }
@@ -266,6 +343,7 @@ void tv_list_drop_items(list_T *const l, listitem_T *const item,
                         listitem_T *const item2)
   FUNC_ATTR_NONNULL_ALL
 {
+  list_log(l, item, item2, "drop");
   // Notify watchers.
   for (listitem_T *ip = item; ip != item2->li_next; ip = ip->li_next) {
     l->lv_len--;
@@ -283,6 +361,7 @@ void tv_list_drop_items(list_T *const l, listitem_T *const item,
     item->li_prev->li_next = item2->li_next;
   }
   l->lv_idx_item = NULL;
+  list_log(l, l->lv_first, l->lv_last, "afterdrop");
 }
 
 /// Like tv_list_drop_items, but also frees all removed items
@@ -290,6 +369,7 @@ void tv_list_remove_items(list_T *const l, listitem_T *const item,
                           listitem_T *const item2)
   FUNC_ATTR_NONNULL_ALL
 {
+  list_log(l, item, item2, "remove");
   tv_list_drop_items(l, item, item2);
   for (listitem_T *li = item;;) {
     tv_clear(TV_LIST_ITEM_TV(li));
@@ -314,6 +394,7 @@ void tv_list_move_items(list_T *const l, listitem_T *const item,
                         const int cnt)
   FUNC_ATTR_NONNULL_ALL
 {
+  list_log(l, item, item2, "move");
   tv_list_drop_items(l, item, item2);
   item->li_prev = tgt_l->lv_last;
   item2->li_next = NULL;
@@ -324,6 +405,7 @@ void tv_list_move_items(list_T *const l, listitem_T *const item,
   }
   tgt_l->lv_last = item2;
   tgt_l->lv_len += cnt;
+  list_log(tgt_l, tgt_l->lv_first, tgt_l->lv_last, "movetgt");
 }
 
 /// Insert list item
@@ -352,6 +434,7 @@ void tv_list_insert(list_T *const l, listitem_T *const ni,
     }
     item->li_prev = ni;
     l->lv_len++;
+    list_log(l, ni, item, "insert");
   }
 }
 
@@ -378,6 +461,7 @@ void tv_list_insert_tv(list_T *const l, typval_T *const tv,
 void tv_list_append(list_T *const l, listitem_T *const item)
   FUNC_ATTR_NONNULL_ALL
 {
+  list_log(l, item, NULL, "append");
   if (l->lv_last == NULL) {
     // empty list
     l->lv_first = item;
@@ -521,7 +605,7 @@ list_T *tv_list_copy(const vimconv_T *const conv, list_T *const orig,
     return NULL;
   }
 
-  list_T *copy = tv_list_alloc();
+  list_T *copy = tv_list_alloc(tv_list_len(orig));
   tv_list_ref(copy);
   if (copyID != 0) {
     // Do this before adding the items, because one of the items may
@@ -741,6 +825,7 @@ void tv_list_reverse(list_T *const l)
   if (tv_list_len(l) <= 1) {
     return;
   }
+  list_log(l, NULL, NULL, "reverse");
 #define SWAP(a, b) \
   do { \
     tmp = a; \
@@ -779,6 +864,7 @@ void tv_list_item_sort(list_T *const l, ListSortItem *const ptrs,
   if (len <= 1) {
     return;
   }
+  list_log(l, NULL, NULL, "sort");
   int i = 0;
   TV_LIST_ITER(l, li, {
     ptrs[i].item = li;
@@ -867,6 +953,7 @@ listitem_T *tv_list_find(list_T *const l, int n)
   // Cache the used index.
   l->lv_idx = idx;
   l->lv_idx_item = item;
+  list_log(l, l->lv_idx_item, (void *)(uintptr_t)l->lv_idx, "find");
 
   return item;
 }
@@ -1817,12 +1904,16 @@ void tv_dict_set_keys_readonly(dict_T *const dict)
 /// Also sets reference count.
 ///
 /// @param[out]  ret_tv  Structure where list is saved.
+/// @param[in]  len  Expected number of items to be populated before list
+///                  becomes accessible from VimL. It is still valid to
+///                  underpopulate a list, value only controls how many elements
+///                  will be allocated in advance. @see ListLenSpecials.
 ///
 /// @return [allocated] pointer to the created list.
-list_T *tv_list_alloc_ret(typval_T *const ret_tv)
+list_T *tv_list_alloc_ret(typval_T *const ret_tv, const ptrdiff_t len)
   FUNC_ATTR_NONNULL_ALL
 {
-  list_T *const l = tv_list_alloc();
+  list_T *const l = tv_list_alloc(len);
   ret_tv->vval.v_list = l;
   ret_tv->v_type = VAR_LIST;
   ret_tv->v_lock = VAR_UNLOCKED;