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

int main() {
    int tt;
    cin >> tt;
    while (tt--) {
        int n;
        cin >> n;
        vector<int> b(n);
        for (int i = 0; i < n; i++) {
            cin >> b[i];
        }
        if (b[0] == -1) {
            b[0] = 0;
        }
        bool fail = false;
        for (int i = 0; i < n - 1; i++) {
            if (b[i + 1] == -1) {
                b[i + 1] = b[i];
            }
            if (b[i + 1] < b[i] || b[i] > i + 1) {
                fail = true;
                break;
            }
        }
        if (fail) {
            cout << -1 << endl;
            continue;
        }
        set<int> st;
        for (int i = 0; i < b[n - 1]; i++) {
            st.emplace(i);
        }
        for (int i = 0; i < n; i++) {
            st.emplace(b[n - 1] + 1 + i);
        }
        vector<int> a(n, -1);
        int last = 0;
        for (int i = 0; i < n; i++) {
            if (b[i] > last) {
                a[i] = last;
                st.erase(last);
                last = b[i];
            }
        }
        for (int i = 0; i < n; i++) {
            if (a[i] == -1) {
                a[i] = *st.begin();
                st.erase(st.begin());
            }
        }
        for (int i = 0; i < n; i++) {
            if (i > 0) {
                cout << " ";
            }
            cout << a[i];
        }
        cout << endl;
    }
    return 0;
}