Merge on predicate throw error on date colum: Unable to convert expression to string

[ibabeo]

Environment

Delta-rs version: 0.16.4

Binding: python

Environment:

• OS: windows
• python: 3.8.17

---

Bug

What happened:
Merge on predicate throw error when the merge key is a date column, which table is partitioned by.

How to reproduce it:

import pandas as pd
from datetime import date
from deltalake import DeltaTable, write_deltalake
import tempfile 

f  = tempfile.TemporaryDirectory().name
df = pd.DataFrame(data={"Date": [date(2023,1,1)] *10 + [date(2024,1,1)]*10, "B":range(20), "C":"constant"})
write_deltalake(f, df, mode='append', partition_by=["Date"])
dt = DeltaTable(f)
df_new = pd.DataFrame(data={"Date":[date(2023,1,1)], "B":[1], "C":"new value"})
dt.merge(source=df_new, predicate='t.Date = s.Date AND t.B = s.B', target_alias='t', source_alias='s').when_matched_update_all().execute()

DeltaError Traceback (most recent call last)
... \lib\site-packages\deltalake\table.py] in execute(self)
1776 Dict: metrics
1777 """
-> 1778 metrics = self.table._table.merge_execute(
1779 source=self.source,
1780 predicate=self.predicate,

DeltaError: Generic DeltaTable error: Unable to convert expression to string

More details:
The same code works in deltalake 0.16.1

[ion-elgreco]

This is already fixed here #2357

And will be available in the next release