Use GroupBy.cumcount with ascending=False by column id and helper Series with Series.cumsum but form back – so added indexing by Series.iloc:
g = f['has_err'].iloc[::-1].cumsum().iloc[::-1]
df['days_to_err'] = df.groupby(['id', g])['has_err'].cumcount(ascending=False)
print(df)
id date info_a_cnt info_b_cnt has_err days_to_err
0 123 2020-01-01 123 32 0 2
1 123 2020-01-02 2 43 0 1
2 123 2020-01-03 43 4 1 0
3 123 2020-01-04 43 4 0 3
4 123 2020-01-05 43 4 0 2
5 123 2020-01-06 43 4 0 1
6 123 2020-01-07 43 4 1 0
7 123 2020-01-08 43 4 0 0
8 232 2020-01-04 56 4 0 3
9 232 2020-01-05 97 1 0 2
10 232 2020-01-06 23 74 0 1
11 232 2020-01-07 91 85 1 0
12 232 2020-01-08 91 85 0 2
13 232 2020-01-09 91 85 0 1
14 232 2020-01-10 91 85 1 0
EDIT: For count cumulative sum of differencies of dates use custom lambda function with GroupBy.transform:
df['days_to_err'] = (df.groupby(['id', df['has_err'].iloc[::-1].cumsum()])['date']
.transform(lambda x: x.diff().dt.days.cumsum())
.fillna(0)
.to_numpy()[::-1])
print(df)
id date info_a_cnt info_b_cnt has_err days_to_err
0 123 2020-01-01 123 32 0 2.0
1 123 2020-01-02 2 43 0 1.0
2 123 2020-01-03 43 4 1 0.0
3 123 2020-01-04 43 4 0 3.0
4 123 2020-01-05 43 4 0 2.0
5 123 2020-01-06 43 4 0 1.0
6 123 2020-01-07 43 4 1 0.0
7 123 2020-01-08 43 4 0 0.0
8 232 2020-01-04 56 4 0 3.0
9 232 2020-01-05 97 1 0 2.0
10 232 2020-01-06 23 74 0 1.0
11 232 2020-01-07 91 85 1 0.0
12 232 2020-01-08 91 85 0 2.0
13 232 2020-01-09 91 85 0 1.0
14 232 2020-01-10 91 85 1 0.0
EDIT1: Use Series.dt.total_seconds with divide by 60:
#some data sample cleaning
df = pd.read_csv("https://pastebin.com/raw/YZukAhBz", parse_dates=['date'])
df['date'] = df['date'].apply(lambda x: x.replace(month=1, day=1))
print(df)
df['days_to_err'] = (df.groupby(['id', df['has_err'].iloc[::-1].cumsum()])['date']
.transform(lambda x: x.diff().dt.total_seconds().div(60).cumsum())
.fillna(0)
.to_numpy()[::-1])
print(df)
id date info_a_cnt info_b_cnt has_err days_to_err
0 123 2020-01-01 12:00:00 123 32 0 30.0
1 123 2020-01-01 12:15:00 2 43 0 15.0
2 123 2020-01-01 12:30:00 43 4 1 0.0
3 123 2020-01-01 12:45:00 43 4 0 45.0
4 123 2020-01-01 13:00:00 43 4 0 30.0
5 123 2020-01-01 13:15:00 43 4 0 15.0
6 123 2020-01-01 13:30:00 43 4 1 0.0
7 123 2020-01-01 13:45:00 43 4 0 0.0
8 232 2020-01-01 17:00:00 56 4 0 45.0
9 232 2020-01-01 17:15:00 97 1 0 30.0
10 232 2020-01-01 17:30:00 23 74 0 15.0
11 232 2020-01-01 17:45:00 91 85 1 0.0
12 232 2020-01-01 18:00:00 91 85 0 30.0
13 232 2020-01-01 18:15:00 91 85 0 15.0
14 232 2020-01-01 18:30:00 91 85 1 0.0
CLICK HERE to find out more related problems solutions.