Vim executing UltiSnips snippet every time I scroll the page

Question

I inserted the 'datetime' snippet from vim-snippets/all.snippet right at the beginning of my document.

The problem is that the time keeps on updating whenever I scroll, as if vim is redrawing the screen and executing the snippet at the same time. What this leads to is, I end up with the time at which the file is closed. Please help me fix the issue.

snippet datetime "YYYY-MM-DD hh:mm" w
`!v strftime("Date: %d %B, %Y | Time: %X")`
endsnippet

UPDATE 1:

UPDATE 2:

base_file

snippet base_file "Competitive Programming Template File" b
/*
**    Date: `!v strftime("%A, %d %B, %Y")`
**    Time: `!v strftime("%X")`
*/

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

#define sz(x) (int)x.size()
#define rep(a, b, i) for (int i = a; i < b; i++)
#define repi(a, b, i) for (int i = a; i > b; i--)
#define F first
#define S second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define __                                                                     \
  ios_base::sync_with_stdio(false);                                            \
  cin.tie(0);                                                                  \
  cout.tie(0)
#define CPU                                                                    \
  cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s." << endl;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;

const int MOD = 1e9 + 7;
const ll inf = 1e18 + 5;
const ld pi = 3.141592653589793;
const int maxn = 1e5 + 5;

int32_t main() {
  __;

  int t;
  cin >> t;
  while (t--) {
    ${1}
  }
  return 0;
}
endsnippet

outputs:

:autocmd CursorHold and :autocmd SafeState are empty

:autocmd CursorMoved

--- Autocommands ---
matchparen  CursorMoved
    *         call s:Highlight_Matching_Pair()
ycmcompletemecursormove  CursorMoved
    *         call s:OnCursorMovedNormalMode()
UltiSnips  CursorMoved
    *         call UltiSnips#CursorMoved()

I randomly tried entering this command: :call UltiSnips#CursorMoved() The same thing happened, i.e. the time updated. I think there is some problem with this command.

Answer 1

From this video:

UltiSnips evaluates each text object that might have a dependency on some types of text multiple times, to make sure that all dependencies are properly updated.

To prevent the date from being updated several times, you could switch to a python interpolation, and use the guard if not snip.c. For example, you could replace this:

**    Time: `!v strftime("%X")`

With this:

**    Time: `!p
if not snip.c:
    from datetime import datetime
    snip.rv = datetime.now().strftime('%X')`

---

Alternatively, try to move your cursor outside the snippet to end its expansion; if you can't, run this:

:sil! py3 UltiSnips_Manager._current_snippet_is_done()

---

For more info about snip.c, read :h UltiSnips-python. See here for a similar issue.