From 1809e75ca6a87f2ca074f2f23ae481c08abc2c11 Mon Sep 17 00:00:00 2001
From: whn <142425816+Whning0513@users.noreply.github.com>
Date: Thu, 30 Jul 2026 05:31:25 +0800
Subject: [PATCH 1/3] Preserve source timezone in chart timestamps

---
 backtesting/_plotting.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/backtesting/_plotting.py b/backtesting/_plotting.py
index 340ea646..6818b46b 100644
--- a/backtesting/_plotting.py
+++ b/backtesting/_plotting.py
@@ -76,6 +76,13 @@ def _windos_safe_filename(filename):
     return filename
 
 
+
+def _remove_timezone(values):
+    if isinstance(values, pd.DatetimeIndex):
+        return values.tz_localize(None) if values.tz is not None else values
+    if isinstance(values, pd.Series) and isinstance(values.dtype, pd.DatetimeTZDtype):
+        return values.dt.tz_localize(None)
+    return values
 def _bokeh_reset(filename=None):
     curstate().reset()
     if filename:
@@ -239,7 +246,7 @@ def plot(*, results: pd.Series,
             resample, df, indicators, equity_data, trades)
 
     df.index.name = None  # Provides source name @index
-    df['datetime'] = df.index  # Save original, maybe datetime index
+    df['datetime'] = _remove_timezone(df.index)  # Save original, maybe datetime index
     df = df.reset_index(drop=True)
     equity_data = equity_data.reset_index(drop=True)
     index = df.index

From 70ab81f3b63cb3347025995edffb717f776f2538 Mon Sep 17 00:00:00 2001
From: whn <142425816+Whning0513@users.noreply.github.com>
Date: Thu, 30 Jul 2026 05:33:02 +0800
Subject: [PATCH 2/3] Normalize trade timestamps for Bokeh

---
 backtesting/_plotting.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/backtesting/_plotting.py b/backtesting/_plotting.py
index 6818b46b..607acc2d 100644
--- a/backtesting/_plotting.py
+++ b/backtesting/_plotting.py
@@ -75,14 +75,14 @@ def _windos_safe_filename(filename):
         return re.sub(r'[^a-zA-Z0-9,_-]', '_', filename.replace('=', '-'))
     return filename
 
-
-
 def _remove_timezone(values):
     if isinstance(values, pd.DatetimeIndex):
         return values.tz_localize(None) if values.tz is not None else values
     if isinstance(values, pd.Series) and isinstance(values.dtype, pd.DatetimeTZDtype):
         return values.dt.tz_localize(None)
     return values
+
+
 def _bokeh_reset(filename=None):
     curstate().reset()
     if filename:
@@ -275,7 +275,7 @@ def plot(*, results: pd.Series,
 
     trade_source = ColumnDataSource(dict(
         index=trades['ExitBar'],
-        datetime=trades['ExitTime'],
+        datetime=_remove_timezone(trades['ExitTime']),
         size=trades['Size'],
         returns_positive=(trades['ReturnPct'] > 0).astype(int).astype(str),
     ))

From bfe44f19bebc2174883d587f3bd613df2c86ee68 Mon Sep 17 00:00:00 2001
From: whn <142425816+Whning0513@users.noreply.github.com>
Date: Thu, 30 Jul 2026 05:33:51 +0800
Subject: [PATCH 3/3] Format timezone helper separation

---
 backtesting/_plotting.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/backtesting/_plotting.py b/backtesting/_plotting.py
index 607acc2d..c53a3e3b 100644
--- a/backtesting/_plotting.py
+++ b/backtesting/_plotting.py
@@ -75,6 +75,7 @@ def _windos_safe_filename(filename):
         return re.sub(r'[^a-zA-Z0-9,_-]', '_', filename.replace('=', '-'))
     return filename
 
+
 def _remove_timezone(values):
     if isinstance(values, pd.DatetimeIndex):
         return values.tz_localize(None) if values.tz is not None else values