From 7b388c52d90d7f9ac5afdd6b22ca1773c281cc05 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Fri, 27 May 2022 18:30:11 +0200
Subject: [PATCH 01/13] Allow all interp options

---
 xarray/core/dataarray.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/xarray/core/dataarray.py b/xarray/core/dataarray.py
index b5bcc255b70..fcdccf7c386 100644
--- a/xarray/core/dataarray.py
+++ b/xarray/core/dataarray.py
@@ -88,7 +88,6 @@
         ErrorOptions,
         ErrorOptionsWithWarn,
         InterpAllOptions,
-        InterpOptions,
         PadModeOptions,
         PadReflectOptions,
         QueryEngineOptions,
@@ -1754,7 +1753,7 @@ def reindex(
     def interp(
         self: T_DataArray,
         coords: Mapping[Any, Any] | None = None,
-        method: InterpOptions = "linear",
+        method: InterpAllOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] | None = None,
         **coords_kwargs: Any,
@@ -1885,7 +1884,7 @@ def interp(
     def interp_like(
         self: T_DataArray,
         other: DataArray | Dataset,
-        method: InterpOptions = "linear",
+        method: InterpAllOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] | None = None,
     ) -> T_DataArray:

From 10e313bf6a9e3ad5ae0a06798d0c03057d02b004 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 09:30:42 +0200
Subject: [PATCH 02/13] renaming the typve variable

---
 xarray/core/dataarray.py | 8 ++++----
 xarray/core/types.py     | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/xarray/core/dataarray.py b/xarray/core/dataarray.py
index fcdccf7c386..0341d84b661 100644
--- a/xarray/core/dataarray.py
+++ b/xarray/core/dataarray.py
@@ -87,7 +87,7 @@
         DatetimeUnitOptions,
         ErrorOptions,
         ErrorOptionsWithWarn,
-        InterpAllOptions,
+        InterpOptions,
         PadModeOptions,
         PadReflectOptions,
         QueryEngineOptions,
@@ -1753,7 +1753,7 @@ def reindex(
     def interp(
         self: T_DataArray,
         coords: Mapping[Any, Any] | None = None,
-        method: InterpAllOptions = "linear",
+        method: InterpOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] | None = None,
         **coords_kwargs: Any,
@@ -1884,7 +1884,7 @@ def interp(
     def interp_like(
         self: T_DataArray,
         other: DataArray | Dataset,
-        method: InterpAllOptions = "linear",
+        method: InterpOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] | None = None,
     ) -> T_DataArray:
@@ -2625,7 +2625,7 @@ def fillna(self: T_DataArray, value: Any) -> T_DataArray:
     def interpolate_na(
         self: T_DataArray,
         dim: Hashable | None = None,
-        method: InterpAllOptions = "linear",
+        method: InterpOptions = "linear",
         limit: int | None = None,
         use_coordinate: bool | str = True,
         max_gap: (
diff --git a/xarray/core/types.py b/xarray/core/types.py
index 38d13c07c3c..e58588906a7 100644
--- a/xarray/core/types.py
+++ b/xarray/core/types.py
@@ -49,10 +49,10 @@
 ]
 JoinOptions = Literal["outer", "inner", "left", "right", "exact", "override"]
 
-InterpOptions = Literal["linear", "nearest", "zero", "slinear", "quadratic", "cubic"]
-Interp1dOptions = Union[InterpOptions, Literal["polynomial"]]
-InterpAllOptions = Union[
-    Interp1dOptions, Literal["barycentric", "krog", "pchip", "spline", "akima"]
+Interp1dOptions = Literal["linear", "nearest", "zero", "slinear", "quadratic", "cubic", "polynomial"]
+InterpolantOptions = Literal["barycentric", "krog", "pchip", "spline", "akima"]
+InterpOptions = Union[
+    Interp1dOptions, InterpolantOptions
 ]
 
 DatetimeUnitOptions = Literal[

From a07f7dc535c9da2b0db9209f703175cfab273d85 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 28 May 2022 07:32:19 +0000
Subject: [PATCH 03/13] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 xarray/core/types.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/xarray/core/types.py b/xarray/core/types.py
index e58588906a7..f4f86bafc93 100644
--- a/xarray/core/types.py
+++ b/xarray/core/types.py
@@ -49,11 +49,11 @@
 ]
 JoinOptions = Literal["outer", "inner", "left", "right", "exact", "override"]
 
-Interp1dOptions = Literal["linear", "nearest", "zero", "slinear", "quadratic", "cubic", "polynomial"]
-InterpolantOptions = Literal["barycentric", "krog", "pchip", "spline", "akima"]
-InterpOptions = Union[
-    Interp1dOptions, InterpolantOptions
+Interp1dOptions = Literal[
+    "linear", "nearest", "zero", "slinear", "quadratic", "cubic", "polynomial"
 ]
+InterpolantOptions = Literal["barycentric", "krog", "pchip", "spline", "akima"]
+InterpOptions = Union[Interp1dOptions, InterpolantOptions]
 
 DatetimeUnitOptions = Literal[
     "Y", "M", "W", "D", "h", "m", "s", "ms", "us", "ns", "ps", "fs", "as"

From b0cc4e10dabc014e1a47ee8934c6cab61ce42ba6 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 09:51:02 +0200
Subject: [PATCH 04/13] use the Literal lists in the interpolator checks

---
 xarray/core/missing.py | 23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 2e869dbe675..990f88a0187 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -4,7 +4,7 @@
 import warnings
 from functools import partial
 from numbers import Number
-from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence
+from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence, get_args
 
 import numpy as np
 import pandas as pd
@@ -18,6 +18,7 @@
 from .pycompat import dask_version, is_duck_dask_array
 from .utils import OrderedSet, is_scalar
 from .variable import Variable, broadcast_variables
+from .types import Interp1dOptions, InterpOptions
 
 if TYPE_CHECKING:
     from .dataarray import DataArray
@@ -469,27 +470,13 @@ def _import_interpolant(interpolant, method):
         raise ImportError(f"Interpolation with method {method} requires scipy.") from e
 
 
-def _get_interpolator(method, vectorizeable_only=False, **kwargs):
+def _get_interpolator(method: InterpOptions, vectorizeable_only: bool =False, **kwargs):
     """helper function to select the appropriate interpolator class
 
     returns interpolator class and keyword arguments for the class
     """
-    interp1d_methods = [
-        "linear",
-        "nearest",
-        "zero",
-        "slinear",
-        "quadratic",
-        "cubic",
-        "polynomial",
-    ]
-    valid_methods = interp1d_methods + [
-        "barycentric",
-        "krog",
-        "pchip",
-        "spline",
-        "akima",
-    ]
+    interp1d_methods = get_args(Interp1dOptions)
+    valid_methods = get_args(InterpOptions)
 
     # prioritize scipy.interpolate
     if (

From e52489cb53d5af34b7bec8f7d7a2b931eb162d23 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 28 May 2022 07:53:00 +0000
Subject: [PATCH 05/13] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 xarray/core/missing.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 990f88a0187..b0990bafe03 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -16,9 +16,9 @@
 from .duck_array_ops import datetime_to_numeric, push, timedelta_to_numeric
 from .options import OPTIONS, _get_keep_attrs
 from .pycompat import dask_version, is_duck_dask_array
+from .types import Interp1dOptions, InterpOptions
 from .utils import OrderedSet, is_scalar
 from .variable import Variable, broadcast_variables
-from .types import Interp1dOptions, InterpOptions
 
 if TYPE_CHECKING:
     from .dataarray import DataArray
@@ -470,7 +470,9 @@ def _import_interpolant(interpolant, method):
         raise ImportError(f"Interpolation with method {method} requires scipy.") from e
 
 
-def _get_interpolator(method: InterpOptions, vectorizeable_only: bool =False, **kwargs):
+def _get_interpolator(
+    method: InterpOptions, vectorizeable_only: bool = False, **kwargs
+):
     """helper function to select the appropriate interpolator class
 
     returns interpolator class and keyword arguments for the class

From 4a5e53a34b379092d4024e5207c9085ccd06b1d4 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 10:12:11 +0200
Subject: [PATCH 06/13] Update missing.py

---
 xarray/core/missing.py | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 990f88a0187..acea365e9fe 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -4,7 +4,7 @@
 import warnings
 from functools import partial
 from numbers import Number
-from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence, get_args
+from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence, Union, get_args
 
 import numpy as np
 import pandas as pd
@@ -310,7 +310,7 @@ def interp_na(
     self,
     dim: Hashable = None,
     use_coordinate: bool | str = True,
-    method: str = "linear",
+    method: InterpOptions = "linear",
     limit: int = None,
     max_gap: int | float | str | pd.Timedelta | np.timedelta64 | dt.timedelta = None,
     keep_attrs: bool = None,
@@ -475,6 +475,8 @@ def _get_interpolator(method: InterpOptions, vectorizeable_only: bool =False, **
 
     returns interpolator class and keyword arguments for the class
     """
+    interp_class: Union[NumpyInterpolator, ScipyInterpolator]
+
     interp1d_methods = get_args(Interp1dOptions)
     valid_methods = get_args(InterpOptions)
 
@@ -584,7 +586,7 @@ def _floatize_x(x, new_x):
     return x, new_x
 
 
-def interp(var, indexes_coords, method, **kwargs):
+def interp(var, indexes_coords, method: InterpOptions, **kwargs):
     """Make an interpolation of Variable
 
     Parameters
@@ -647,7 +649,7 @@ def interp(var, indexes_coords, method, **kwargs):
     return result
 
 
-def interp_func(var, x, new_x, method, kwargs):
+def interp_func(var, x, new_x, method: InterpOptions, kwargs):
     """
     multi-dimensional interpolation for array-like. Interpolated axes should be
     located in the last position.

From 93837fba1b42ef32fdce4f98a95518835823b6c4 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 28 May 2022 08:14:00 +0000
Subject: [PATCH 07/13] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 xarray/core/missing.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index af17811b121..0527028da63 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -477,7 +477,7 @@ def _get_interpolator(
 
     returns interpolator class and keyword arguments for the class
     """
-    interp_class: Union[NumpyInterpolator, ScipyInterpolator]
+    interp_class: NumpyInterpolator | ScipyInterpolator
 
     interp1d_methods = get_args(Interp1dOptions)
     valid_methods = get_args(InterpOptions)

From 043ca5fd6e70860c9768ec6e9d3548590a2eaa56 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 10:27:34 +0200
Subject: [PATCH 08/13] more fixes

---
 xarray/core/dataset.py | 3 ++-
 xarray/core/missing.py | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/xarray/core/dataset.py b/xarray/core/dataset.py
index c5c727f4bed..aa85f99d430 100644
--- a/xarray/core/dataset.py
+++ b/xarray/core/dataset.py
@@ -109,6 +109,7 @@
         CompatOptions,
         ErrorOptions,
         ErrorOptionsWithWarn,
+        InterpOptions,
         JoinOptions,
         PadModeOptions,
         PadReflectOptions,
@@ -3037,7 +3038,7 @@ def _reindex(
     def interp(
         self,
         coords: Mapping[Any, Any] = None,
-        method: str = "linear",
+        method: InterpOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] = None,
         method_non_numeric: str = "nearest",
diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 0527028da63..4abc27f1fbf 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -477,7 +477,7 @@ def _get_interpolator(
 
     returns interpolator class and keyword arguments for the class
     """
-    interp_class: NumpyInterpolator | ScipyInterpolator
+    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator]
 
     interp1d_methods = get_args(Interp1dOptions)
     valid_methods = get_args(InterpOptions)

From 4653e589e3cd6a460d035c62be9b314a1a456ddb Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 28 May 2022 08:29:09 +0000
Subject: [PATCH 09/13] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 xarray/core/missing.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 4abc27f1fbf..393367eba37 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -4,7 +4,7 @@
 import warnings
 from functools import partial
 from numbers import Number
-from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence, Union, get_args
+from typing import TYPE_CHECKING, Any, Callable, Hashable, Sequence, get_args
 
 import numpy as np
 import pandas as pd

From 5af2fe31e9742854747acf6d9d6ebe4331a0f07e Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 10:45:13 +0200
Subject: [PATCH 10/13] more fixes

---
 xarray/core/dataset.py | 2 +-
 xarray/core/missing.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/xarray/core/dataset.py b/xarray/core/dataset.py
index aa85f99d430..084437e102c 100644
--- a/xarray/core/dataset.py
+++ b/xarray/core/dataset.py
@@ -3299,7 +3299,7 @@ def _validate_interp_indexer(x, new_x):
     def interp_like(
         self,
         other: Dataset | DataArray,
-        method: str = "linear",
+        method: InterpOptions = "linear",
         assume_sorted: bool = False,
         kwargs: Mapping[str, Any] = None,
         method_non_numeric: str = "nearest",
diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 4abc27f1fbf..cfd9a0253cc 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -641,7 +641,7 @@ def interp(var, indexes_coords, method: InterpOptions, **kwargs):
         result = Variable(new_dims, interped, attrs=var.attrs)
 
         # dimension of the output array
-        out_dims = OrderedSet()
+        out_dims: OrderedSet = OrderedSet()
         for d in var.dims:
             if d in dims:
                 out_dims.update(indexes_coords[d][1].dims)

From 4dc66286611bd579487004a0ce8d77d77947812f Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 11:32:19 +0200
Subject: [PATCH 11/13] Get the args of Literals that's inside of the Union

---
 xarray/core/missing.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 02f2a977929..2bcabe081cb 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -477,10 +477,10 @@ def _get_interpolator(
 
     returns interpolator class and keyword arguments for the class
     """
-    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator]
+    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator] | Type[SplineInterpolator]
 
     interp1d_methods = get_args(Interp1dOptions)
-    valid_methods = get_args(InterpOptions)
+    valid_methods = tuple(vv for v in get_args(InterpOptions) for vv in get_args(v))
 
     # prioritize scipy.interpolate
     if (

From acff97f9ae6bc8c36ff9ed3e8f9569d29171e54d Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Sat, 28 May 2022 09:33:56 +0000
Subject: [PATCH 12/13] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 xarray/core/missing.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 2bcabe081cb..698d767ed6e 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -477,7 +477,9 @@ def _get_interpolator(
 
     returns interpolator class and keyword arguments for the class
     """
-    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator] | Type[SplineInterpolator]
+    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator] | Type[
+        SplineInterpolator
+    ]
 
     interp1d_methods = get_args(Interp1dOptions)
     valid_methods = tuple(vv for v in get_args(InterpOptions) for vv in get_args(v))

From b254513817b8b8cfbf62868e49b92ea8800e9729 Mon Sep 17 00:00:00 2001
From: Illviljan <14371165+Illviljan@users.noreply.github.com>
Date: Sat, 28 May 2022 12:02:30 +0200
Subject: [PATCH 13/13] Update missing.py

---
 xarray/core/missing.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xarray/core/missing.py b/xarray/core/missing.py
index 2bcabe081cb..81966534355 100644
--- a/xarray/core/missing.py
+++ b/xarray/core/missing.py
@@ -477,7 +477,7 @@ def _get_interpolator(
 
     returns interpolator class and keyword arguments for the class
     """
-    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator] | Type[SplineInterpolator]
+    interp_class: type[NumpyInterpolator] | type[ScipyInterpolator] | type[SplineInterpolator]
 
     interp1d_methods = get_args(Interp1dOptions)
     valid_methods = tuple(vv for v in get_args(InterpOptions) for vv in get_args(v))