Mandate kwargs on to_zarr (#8257)

* Mandate kwargs on `to_zarr`

This aleviates some of the dangers of having these in a different order between `da` & `ds`.

_Technically_ it's a breaking change, but only very technically, given that I would wager literally no one has a dozen positional arguments to this method. So I think it's OK.

Author: max-sixty

doc/whats-new.rst

@@ -30,6 +30,10 @@ New Features
 Breaking changes
 ~~~~~~~~~~~~~~~~
 
+- :py:meth:`Dataset.to_zarr` & :py:meth:`DataArray.to_zarr` require keyword
+  arguments after the initial 7 positional arguments.
+  By `Maximilian Roos <https://github.com/max-sixty>`_.
+
 
 Deprecations
 ~~~~~~~~~~~~

xarray/backends/api.py

@@ -1528,6 +1528,7 @@ def to_zarr(
     synchronizer=None,
     group: str | None = None,
     encoding: Mapping | None = None,
+    *,
     compute: Literal[True] = True,
     consolidated: bool | None = None,
     append_dim: Hashable | None = None,
@@ -1573,6 +1574,7 @@ def to_zarr(
     synchronizer=None,
     group: str | None = None,
     encoding: Mapping | None = None,
+    *,
     compute: bool = True,
     consolidated: bool | None = None,
     append_dim: Hashable | None = None,

xarray/core/dataarray.py

@@ -4010,6 +4010,7 @@ def to_zarr(
         mode: Literal["w", "w-", "a", "r+", None] = None,
         synchronizer=None,
         group: str | None = None,
+        *,
         encoding: Mapping | None = None,
         compute: Literal[True] = True,
         consolidated: bool | None = None,
@@ -4050,6 +4051,7 @@ def to_zarr(
         synchronizer=None,
         group: str | None = None,
         encoding: Mapping | None = None,
+        *,
         compute: bool = True,
         consolidated: bool | None = None,
         append_dim: Hashable | None = None,

xarray/core/dataset.py

@@ -2293,6 +2293,7 @@ def to_zarr(
         synchronizer=None,
         group: str | None = None,
         encoding: Mapping | None = None,
+        *,
         compute: Literal[True] = True,
         consolidated: bool | None = None,
         append_dim: Hashable | None = None,
@@ -2336,6 +2337,7 @@ def to_zarr(
         synchronizer=None,
         group: str | None = None,
         encoding: Mapping | None = None,
+        *,
         compute: bool = True,
         consolidated: bool | None = None,
         append_dim: Hashable | None = None,