formatting

pint/delegates/formatter/full.py

@@ -37,6 +37,7 @@
         PlainQuantity,
         PlainUnit,
     )
+    from ...facets.kind import KindKind, QuantityKind
     from ...registry import UnitRegistry
 
 
@@ -130,6 +131,19 @@ def format_unit(
             unit, uspec, sort_func=sort_func, **babel_kwds
         )
 
+    def format_kind(
+        self,
+        kind: KindKind | Iterable[tuple[str, Any]],
+        uspec: str = "",
+        sort_func: SortFunc | None = None,
+        **babel_kwds: Unpack[BabelKwds],
+    ) -> str:
+        uspec = uspec or self.default_format
+        sort_func = sort_func or self.default_sort_func
+        return self.get_formatter(uspec).format_kind(
+            kind, uspec, sort_func=sort_func, **babel_kwds
+        )
+
     def format_quantity(
         self,
         quantity: PlainQuantity[MagnitudeT],
@@ -166,6 +180,20 @@ def format_quantity(
             length=babel_kwds.get("length", None),
             locale=locale,
         )
+
+    def format_quantitykind(
+        self,
+        quantitykind: QuantityKind | Iterable[tuple[str, Any]],
+        uspec: str = "",
+        sort_func: SortFunc | None = None,
+        **babel_kwds: Unpack[BabelKwds],
+    ) -> str:
+        uspec = uspec or self.default_format
+        sort_func = sort_func or self.default_sort_func
+        return self.get_formatter(uspec).format_quantitykind(
+            quantitykind, uspec, sort_func=sort_func, **babel_kwds
+        )
+
 
     def format_measurement(
         self,

pint/delegates/formatter/plain.py

@@ -39,6 +39,7 @@
 )
 
 if TYPE_CHECKING:
+    from ...facets.kind import KindKind
     from ...facets.measurement import Measurement
     from ...facets.plain import MagnitudeT, PlainQuantity, PlainUnit
     from ...registry import UnitRegistry
@@ -51,6 +52,42 @@ class BaseFormatter:
     def __init__(self, registry: UnitRegistry | None = None):
         self._registry = registry
 
+    def format_kind(
+        self,
+        kind: KindKind | Iterable[tuple[str, Any]],
+        uspec: str = "",
+        sort_func: SortFunc | None = None,
+        **babel_kwds: Unpack[BabelKwds],
+    ) -> str:
+        """Format a unit (can be compound) into string
+        given a string formatting specification and locale related arguments.
+        """
+        kind = kind._kinds
+        return self.format_unit(kind, uspec, sort_func, **babel_kwds)
+
+    def format_quantitykind(
+        self,
+        quantitykind: QuantityKind,
+        qspec: str = "",
+        sort_func: SortFunc | None = None,
+        **babel_kwds: Unpack[BabelKwds],
+    ) -> str:
+        """Format a quantitykind into string
+        given a string formatting specification and locale related arguments.
+        """
+        quantity = quantitykind.quantity
+
+        registry = self._registry
+
+        mspec, uspec = split_format(
+            qspec, registry.formatter.default_format, registry.separate_format_defaults
+        )
+
+        mu = self.format_quantity(quantity, qspec, sort_func, **babel_kwds)
+        k = self.format_kind(quantitykind.kinds, uspec, sort_func, **babel_kwds)
+        return mu + " " + k
+
+
 
 class DefaultFormatter(BaseFormatter):
     """Simple, localizable plain text formatter.
@@ -112,6 +149,7 @@ def format_unit(
             parentheses_fmt=r"({})",
         )
 
+
     def format_quantity(
         self,
         quantity: PlainQuantity[MagnitudeT],

pint/facets/kind/objects.py

@@ -109,7 +109,7 @@ def __new__(cls, value, kinds, units=None):
                     "units must be of type str, PlainQuantity or "
                     "UnitsContainer; not {}.".format(type(units))
                 )
-        if isinstance(value, cls):
+        if isinstance(value, PlainQuantity):
             magnitude = value.to(units)._magnitude
         else:
             magnitude = _to_magnitude(
@@ -121,17 +121,15 @@ def __new__(cls, value, kinds, units=None):
 
         return inst
 
-    def __repr__(self):
-        return "<QuantityKind({}, {}, {})>".format(
-            self.magnitude, self._kinds, self.units
-        )
+    def __repr__(self) -> str:
+        return f"<QuantityKind({self._magnitude}, {self._units}, {self._kinds})>"
 
     def __str__(self):
         return f"{self}"
 
-    # def __format__(self, spec):
-    #     spec = spec or self._REGISTRY.default_format
-    #     return self._REGISTRY.formatter.format_measurement(self, spec)
+    def __format__(self, spec):
+        spec = spec or self._REGISTRY.default_format
+        return self._REGISTRY.formatter.format_quantitykind(self, spec)
 
     @property
     def kinds(self) -> KindKind:

pint/util.py

@@ -962,7 +962,8 @@ def _is_dim(name: str) -> bool:
 
 
 class SharedRegistryObject:
-    """
+    """Base class for object keeping a reference to the registree.
+
     Such object are for now Quantity and Unit, in a number of places it is
     that an object from this class has a '_units' attribute.
 
@@ -1016,7 +1017,6 @@ def _check(self, other: Any) -> bool:
             return False
 
 
-
 class PrettyIPython:
     """Mixin to add pretty-printers for IPython"""