fix: more useful repr for stack (#449)

* fix: nicer stack repr

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

* fix: avoid listing label when unset

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

Signed-off-by: Henry Schreiner <henryschreineriii@gmail.com>

Author: henryiii

docs/changelog.md

@@ -1,5 +1,19 @@
 # Changelog
 
+## Version 2.6.2
+
+* Nicer stacks repr
+  [#449](https://github.com/scikit-hep/hist/pull/449)
+* Backport `storage_type` if boost-histogram < 1.3.2
+  [#447](https://github.com/scikit-hep/hist/pull/447)
+* Allow overwriting labels for plot/overlay
+  [#414](https://github.com/scikit-hep/hist/pull/414)
+* Use Hatching to build the package
+  [#418](https://github.com/scikit-hep/hist/pull/418)
+* Support git archival version numbers
+  [#441](https://github.com/scikit-hep/hist/pull/441)
+
+
 ## Version 2.6.1
 
 * Fall back on normal repr when histogram is too large

src/hist/axis/__init__.py

@@ -82,7 +82,7 @@ def _repr_args_(self: AxisProtocol) -> list[str]:
 
         if self.name:
             ret.append(f"name={self.name!r}")
-        if self.label:
+        if self.label and self.label != self.name:
             ret.append(f"label={self.label!r}")
 
         return ret

src/hist/stack.py

@@ -111,8 +111,9 @@ def __len__(self) -> int:
         return len(self._stack)
 
     def __repr__(self) -> str:
-        str_stack = ", ".join(repr(h) for h in self)
-        return f"{self.__class__.__name__}({str_stack})"
+        names = ", ".join(repr(getattr(h, "name", f"H{i}")) for i, h in enumerate(self))
+        h = repr(self[0]) if len(self) else "Empty stack"
+        return f"{self.__class__.__name__}<({names}) of {h}>"
 
     def __eq__(self, other: Any) -> bool:
         if not isinstance(other, Stack):