Bugfix/adjust (#92)

* bugfix

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update changelog

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -10,6 +10,9 @@ Keep it human-readable, your future self will thank you!
 
 ## [Unreleased](https://github.com/ecmwf/anemoi-datasets/compare/0.5.7...HEAD)
 
+### Changed
+
+- Bugfix in `auto_adjust`
 
 ### Added
 

src/anemoi/datasets/data/misc.py

@@ -235,16 +235,21 @@ def _auto_adjust(datasets, kwargs):
             if set(d.variables) != variables:
                 subset_kwargs[i]["select"] = sorted(variables)
 
+    if "start" or "end" in adjust_set:
+        common = datasets[0].dates
+        for d in datasets[0:]:
+            common = np.intersect1d(common, d.dates)
+
     if "start" in adjust_set:
         assert "start" not in kwargs, "Cannot use 'start' in adjust and kwargs"
-        start = max(d.dates[0] for d in datasets).astype(object)
+        start = min(common).astype(object)
         for i, d in enumerate(datasets):
             if start != d.dates[0]:
                 subset_kwargs[i]["start"] = start
 
     if "end" in adjust_set:
         assert "end" not in kwargs, "Cannot use 'end' in adjust and kwargs"
-        end = min(d.dates[-1] for d in datasets).astype(object)
+        end = max(common).astype(object)
         for i, d in enumerate(datasets):
             if end != d.dates[-1]:
                 subset_kwargs[i]["end"] = end