From 6d1122be2a25cbd726536ac92061156fd7a9a0b4 Mon Sep 17 00:00:00 2001
From: Lasse <lasseh0310@gmail.com>
Date: Thu, 22 Feb 2024 15:17:20 +0100
Subject: [PATCH 1/2] fix(#480): pure NaNs when flattening with
 lookbehind-tuple in 01_basic

Fixes #480
---
 docs/tutorials/01_basic.ipynb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/tutorials/01_basic.ipynb b/docs/tutorials/01_basic.ipynb
index e34e455f..094d0345 100644
--- a/docs/tutorials/01_basic.ipynb
+++ b/docs/tutorials/01_basic.ipynb
@@ -51,7 +51,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 1,
    "metadata": {},
    "outputs": [
     {

From 3ade969b3db28aba52690afefa855b8cc8c9cc2f Mon Sep 17 00:00:00 2001
From: Lasse <lasseh0310@gmail.com>
Date: Thu, 22 Feb 2024 15:46:38 +0100
Subject: [PATCH 2/2] fix: bug in `_get_timedelta_frame` if timestamp col names
 were the same

---
 .../spec_processors/temporal.py               | 11 +++++---
 .../spec_processors/test_temporal.py          | 25 +++++++++++++++++++
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/src/timeseriesflattenerv2/spec_processors/temporal.py b/src/timeseriesflattenerv2/spec_processors/temporal.py
index 5639aa24..e220e253 100644
--- a/src/timeseriesflattenerv2/spec_processors/temporal.py
+++ b/src/timeseriesflattenerv2/spec_processors/temporal.py
@@ -24,15 +24,20 @@ def _get_timedelta_frame(
     predictiontime_frame: PredictionTimeFrame, value_frame: ValueFrame
 ) -> TimeDeltaFrame:
     # Join the prediction time dataframe
-    joined_frame = predictiontime_frame.df.join(
-        value_frame.df, on=predictiontime_frame.entity_id_col_name, how="left"
+    # ensure that the timestamp col names are different to avoid conflicts
+    unique_predictiontime_frame_timestamp_col_name = (
+        f"__{predictiontime_frame.timestamp_col_name}__"
     )
 
+    joined_frame = predictiontime_frame.df.rename(
+        {predictiontime_frame.timestamp_col_name: unique_predictiontime_frame_timestamp_col_name}
+    ).join(value_frame.df, on=predictiontime_frame.entity_id_col_name, how="left")
+
     # Get timedelta
     timedelta_frame = joined_frame.with_columns(
         (
             pl.col(value_frame.value_timestamp_col_name)
-            - pl.col(predictiontime_frame.timestamp_col_name)
+            - pl.col(unique_predictiontime_frame_timestamp_col_name)
         ).alias("time_from_prediction_to_value")
     )
 
diff --git a/src/timeseriesflattenerv2/spec_processors/test_temporal.py b/src/timeseriesflattenerv2/spec_processors/test_temporal.py
index bd77a7aa..428de6a4 100644
--- a/src/timeseriesflattenerv2/spec_processors/test_temporal.py
+++ b/src/timeseriesflattenerv2/spec_processors/test_temporal.py
@@ -117,6 +117,31 @@ def test_get_timedelta_frame():
     assert result.get_timedeltas() == expected_timedeltas
 
 
+def test_get_timedelta_frame_same_timestamp_col_names():
+    pred_frame = str_to_pl_df(
+        """entity_id,timestamp
+            1,2021-01-03"""
+    )
+
+    value_frame = str_to_pl_df(
+        """entity_id,value,timestamp
+        1,1,2021-01-01
+        1,2,2021-01-02
+        1,3,2021-01-03"""
+    )
+
+    expected_timedeltas = [dt.timedelta(days=-2), dt.timedelta(days=-1), dt.timedelta(days=0)]
+
+    result = process_spec._get_timedelta_frame(
+        predictiontime_frame=PredictionTimeFrame(
+            init_df=pred_frame.lazy(), timestamp_col_name="timestamp"
+        ),
+        value_frame=ValueFrame(init_df=value_frame.lazy()),
+    )
+
+    assert result.get_timedeltas() == expected_timedeltas
+
+
 def test_slice_without_any_within_window():
     timedelta_frame = TimeDeltaFrame(
         df=pl.LazyFrame(