From b46633f31ddb79d712c6115639660bf157ca4515 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 13 May 2024 21:21:58 +0000
Subject: [PATCH 01/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.3 → v0.4.4](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.3...v0.4.4)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d2dd579f..4fcbb07b 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.3
+  rev: v0.4.4
   hooks:
   - id: ruff
 

From 9fb921abfd6c937f5c2870029cf2361fe7f7bd41 Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 15 May 2024 09:34:09 -0400
Subject: [PATCH 02/22] Implement dak.nan_to_num

---
 src/dask_awkward/lib/structure.py | 24 +++++++++---------------
 tests/test_structure.py           |  9 +++++++++
 2 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/src/dask_awkward/lib/structure.py b/src/dask_awkward/lib/structure.py
index 6b9fafad..ae5f104f 100644
--- a/src/dask_awkward/lib/structure.py
+++ b/src/dask_awkward/lib/structure.py
@@ -600,26 +600,20 @@ def mask(
 @borrow_docstring(ak.nan_to_num)
 def nan_to_num(
     array: Array,
-    copy: bool = True,
     nan: float = 0.0,
     posinf: Any | None = None,
     neginf: Any | None = None,
-    highlevel: bool = True,
     behavior: Any | None = None,
-    attrs: Mapping[str, Any] | None = None,
 ) -> Array:
-    # return map_partitions(
-    #     ak.nan_to_num,
-    #     array,
-    #     output_partitions=1,
-    #     copy=copy,
-    #     nan=nan,
-    #     posinf=posinf,
-    #     neginf=neginf,
-    #     highlevel=highlevel,
-    #     behavior=behavior,
-    # )
-    raise DaskAwkwardNotImplemented("TODO")
+    return map_partitions(
+        ak.nan_to_num,
+        array,
+        nan=nan,
+        posinf=posinf,
+        neginf=neginf,
+        highlevel=True,
+        behavior=behavior,
+    )
 
 
 def _numaxis0(*integers):
diff --git a/tests/test_structure.py b/tests/test_structure.py
index 180e922e..d196ee35 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -157,6 +157,15 @@ def test_drop_none(axis: int) -> None:
     assert_eq(d, e)
 
 
+def test_nan_to_num():
+    a = [[1, 2, np.nan], [], [np.nan], [5, 6, 7, np.nan], [1, 2], np.nan]
+    b = [[np.nan, 2, 1], [np.nan], [], np.nan, [7, 6, np.nan, 5], [np.nan, np.nan]]
+    c = dak.from_lists([a, b])
+    d = dak.nan_to_num(c, nan=5)
+    e = ak.nan_to_num(ak.from_iter(a + b), nan=5)
+    assert_eq(d, e)
+
+
 @pytest.mark.parametrize("axis", [0, 1, -1])
 def test_is_none(axis: int) -> None:
     a: list[Any] = [[1, 2, None], None, None, [], [None], [5, 6, 7, None], [1, 2], None]

From 77b7ea1824c9f7b1eeef2c38ba336aa91e64ba5e Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 15 May 2024 09:43:38 -0400
Subject: [PATCH 03/22] lint

---
 tests/test_optimize.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_optimize.py b/tests/test_optimize.py
index 7f67d836..80fb975f 100644
--- a/tests/test_optimize.py
+++ b/tests/test_optimize.py
@@ -28,7 +28,7 @@ def test_multiple_computes(ndjson_points_file: str) -> None:
     assert len(things3[1]) < len(things3[0])
 
     things = dask.compute(ds1.points, ds2.points.x, ds2.points.y, ds1.points.y, ds3)
-    assert things[-1].tolist() == ak.Array(lists[0] + lists[1]).tolist()  # type: ignore
+    assert things[-1].tolist() == ak.Array(lists[0] + lists[1]).tolist()
 
 
 def identity(x):

From cc00adda140b96320595057856db92b33b47b166 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 27 May 2024 21:21:56 +0000
Subject: [PATCH 04/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.4 → v0.4.5](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.4...v0.4.5)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 4fcbb07b..4b24a5f5 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.4
+  rev: v0.4.5
   hooks:
   - id: ruff
 

From a0e75e48744b542b90bf74a6ef2a0d75aadc5c0d Mon Sep 17 00:00:00 2001
From: Iason Krommydas <iason.krom@gmail.com>
Date: Fri, 31 May 2024 15:22:22 +0200
Subject: [PATCH 05/22] add without_field, untested yet

---
 src/dask_awkward/__init__.py      |  1 +
 src/dask_awkward/lib/__init__.py  |  1 +
 src/dask_awkward/lib/structure.py | 41 +++++++++++++++++++++++++++++++
 3 files changed, 43 insertions(+)

diff --git a/src/dask_awkward/__init__.py b/src/dask_awkward/__init__.py
index 9b205092..34b5c4f5 100644
--- a/src/dask_awkward/__init__.py
+++ b/src/dask_awkward/__init__.py
@@ -100,6 +100,7 @@
     with_field,
     with_name,
     with_parameter,
+    without_field,
     without_parameters,
     zeros_like,
     zip,
diff --git a/src/dask_awkward/lib/__init__.py b/src/dask_awkward/lib/__init__.py
index 90835ff7..74d16d6c 100644
--- a/src/dask_awkward/lib/__init__.py
+++ b/src/dask_awkward/lib/__init__.py
@@ -86,6 +86,7 @@
     with_field,
     with_name,
     with_parameter,
+    without_field,
     without_parameters,
     zeros_like,
     zip,
diff --git a/src/dask_awkward/lib/structure.py b/src/dask_awkward/lib/structure.py
index ae5f104f..d7e52ed1 100644
--- a/src/dask_awkward/lib/structure.py
+++ b/src/dask_awkward/lib/structure.py
@@ -70,6 +70,7 @@
     "values_astype",
     "where",
     "with_field",
+    "without_field",
     "with_name",
     "with_parameter",
     "without_parameters",
@@ -1083,6 +1084,46 @@ def with_field(
     )
 
 
+class _WithoutFieldFn:
+    def __init__(
+        self,
+        highlevel: bool,
+        behavior: Mapping | None = None,
+        attrs: Mapping[str, Any] | None = None,
+    ) -> None:
+        self.highlevel = highlevel
+        self.behavior = behavior
+        self.attrs = attrs
+
+    def __call__(self, array: ak.Array, where: str) -> ak.Array:
+        return ak.without_field(
+            array, where=where, behavior=self.behavior, attrs=self.attrs
+        )
+
+
+@borrow_docstring(ak.without_field)
+def without_field(
+    base: Array,
+    where: str,
+    highlevel: bool = True,
+    behavior: Mapping | None = None,
+    attrs: Mapping[str, Any] | None = None,
+) -> Array:
+    if not highlevel:
+        raise ValueError("Only highlevel=True is supported")
+
+    if not isinstance(base, Array):
+        raise ValueError("Base argument in without_field must be a dask_awkward.Array")
+
+    return map_partitions(
+        _WithoutFieldFn(highlevel=highlevel, behavior=behavior, attrs=attrs),
+        base,
+        where,
+        label="without-field",
+        output_divisions=1,
+    )
+
+
 class _WithNameFn:
     def __init__(
         self,

From 3a38bf614981831ed11b3d1eb8404201318fcd46 Mon Sep 17 00:00:00 2001
From: Iason Krommydas <iason.krom@gmail.com>
Date: Fri, 31 May 2024 15:51:14 +0200
Subject: [PATCH 06/22] some testing

---
 tests/test_structure.py | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/tests/test_structure.py b/tests/test_structure.py
index d196ee35..f602e11e 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -212,20 +212,20 @@ def test_pad_none(axis: int, target: int) -> None:
 
 
 def test_with_field(caa: ak.Array, daa: dak.Array) -> None:
-    assert_eq(
-        ak.with_field(caa["points"], caa["points"]["x"], where="xx"),
-        dak.with_field(daa["points"], daa["points"]["x"], where="xx"),
-    )
+    new_caa = ak.with_field(caa["points"], caa["points"]["x"], where="xx")
+    new_daa = dak.with_field(daa["points"], daa["points"]["x"], where="xx")
+    assert_eq(new_caa, new_daa)
+    assert_eq(ak.without_field(new_caa, "xx"), ak.without_field(new_daa, "xx"))
 
-    assert_eq(
-        ak.with_field(caa["points"], 1, where="xx"),
-        dak.with_field(daa["points"], 1, where="xx"),
-    )
+    new_caa = ak.with_field(caa["points"], 1, where="xx")
+    new_daa = dak.with_field(daa["points"], 1, where="xx")
+    assert_eq(new_caa, new_daa)
+    assert_eq(ak.without_field(new_caa, "xx"), ak.without_field(new_daa, "xx"))
 
-    assert_eq(
-        ak.with_field(caa["points"], 1.0, where="xx"),
-        dak.with_field(daa["points"], 1.0, where="xx"),
-    )
+    new_caa = ak.with_field(caa["points"], 1.0, where="xx")
+    new_daa = dak.with_field(daa["points"], 1.0, where="xx")
+    assert_eq(new_caa, new_daa)
+    assert_eq(ak.without_field(new_caa, "xx"), ak.without_field(new_daa, "xx"))
 
     with pytest.raises(
         ValueError,
@@ -233,6 +233,15 @@ def test_with_field(caa: ak.Array, daa: dak.Array) -> None:
     ):
         _ = dak.with_field([{"foo": 1.0}, {"foo": 2.0}], daa.points.x, where="x")
 
+    with pytest.raises(
+        ValueError,
+        match="Base argument in without_field must be a dask_awkward.Array",
+    ):
+        _ = dak.without_field(
+            [{"foo": [1.0, 2.0], "bar": [3.0, 4.0]}],
+            "bar",
+        )
+
     with pytest.raises(
         ValueError,
         match="with_field cannot accept string, bytes, list, or dict values yet",

From ca3ad7a706b2612af1ff709a92213edc9790507f Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 3 Jun 2024 21:35:59 +0000
Subject: [PATCH 07/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.5 → v0.4.7](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.5...v0.4.7)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 4b24a5f5..84dde665 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.5
+  rev: v0.4.7
   hooks:
   - id: ruff
 

From fde5c808ea6f6135308d5e9b5fb7e42040c64973 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 10 Jun 2024 21:44:22 +0000
Subject: [PATCH 08/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.7 → v0.4.8](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.7...v0.4.8)
- [github.com/asottile/pyupgrade: v3.15.2 → v3.16.0](https://github.com/asottile/pyupgrade/compare/v3.15.2...v3.16.0)
---
 .pre-commit-config.yaml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 84dde665..cf0308b5 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.7
+  rev: v0.4.8
   hooks:
   - id: ruff
 
@@ -35,7 +35,7 @@ repos:
     language_version: python3
 
 - repo: https://github.com/asottile/pyupgrade
-  rev: v3.15.2
+  rev: v3.16.0
   hooks:
   - id: pyupgrade
     args:

From 21eca160a5bf4032167bd973e9789420266b6c70 Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 12 Jun 2024 21:30:50 -0400
Subject: [PATCH 09/22] Make simple types of repartition

---
 src/dask_awkward/lib/core.py      | 84 ++++++++++++++++++++++++-------
 src/dask_awkward/lib/structure.py | 43 ++++++++++++++++
 tests/test_structure.py           |  6 +++
 3 files changed, 114 insertions(+), 19 deletions(-)

diff --git a/src/dask_awkward/lib/core.py b/src/dask_awkward/lib/core.py
index 40898b11..204ccc3f 100644
--- a/src/dask_awkward/lib/core.py
+++ b/src/dask_awkward/lib/core.py
@@ -942,29 +942,75 @@ def repartition(
         npartitions: int | None = None,
         divisions: tuple[int, ...] | None = None,
         rows_per_partition: int | None = None,
+        one_to_n: int | None = None,
+        n_to_one: int | None = None,
     ) -> Array:
+        """Restructure the partitioning of the whole array
+
+        Various schemes are possible, with one of the mutually exclusive
+        optional arguments for each. Of these, the first three require
+        knowledge of the number of rows in each existing partition, which
+        will be eagerly computed if not already known, and some shuffling of
+        data between partitions.
+
+        - npartitions: split all the rows as evenly as possible into this
+          many output partitions.
+        - divisions: exact row count offsets of each output partition
+        - rows_per_partition: each partition will have this many rows,
+          except the last, which will have this number or fewer
+        - one_to_n: each input partition becomes n output partitions
+        - n_to_one: every n adjacent input partitions becomes one
+          output partition. Note that exactly one output partition
+          (npartitions=1) is a special case of this.
+        """
         from dask_awkward.layers import AwkwardMaterializedLayer
-        from dask_awkward.lib.structure import repartition_layer
+        from dask_awkward.lib.structure import (
+            repartition_layer,
+            simple_repartition_layer,
+        )
 
-        if sum(bool(_) for _ in [npartitions, divisions, rows_per_partition]) != 1:
+        if (
+            sum(
+                bool(_)
+                for _ in (
+                    npartitions,
+                    divisions,
+                    rows_per_partition,
+                    one_to_n,
+                    n_to_one,
+                )
+            )
+            != 1
+        ):
             raise ValueError("Please specify exactly one of the inputs")
-        if not self.known_divisions:
-            self.eager_compute_divisions()
-        nrows = self.defined_divisions[-1]
-        new_divisions: tuple[int, ...] = tuple()
-        if divisions:
-            new_divisions = divisions
-        elif npartitions:
-            rows_per_partition = math.ceil(nrows / npartitions)
-        if rows_per_partition:
-            new_divs = list(range(0, nrows, rows_per_partition))
-            new_divs.append(nrows)
-            new_divisions = tuple(new_divs)
-
-        token = tokenize(self, divisions)
-        key = f"repartition-{token}"
-
-        new_layer_raw = repartition_layer(self, key, new_divisions)
+        new_divisions: tuple[int, ...] = ()
+        if npartitions and npartitions == 1:
+            npartitions, n_to_one = None, self.npartitions
+        if n_to_one or one_to_n:
+            token = tokenize(self, n_to_one, one_to_n)
+            key = f"repartition-{token}"
+            new_layer_raw, new_divisions = simple_repartition_layer(
+                self, n_to_one, one_to_n, key
+            )
+        else:
+            if not self.known_divisions:
+                self.eager_compute_divisions()
+            nrows = self.defined_divisions[-1]
+            if divisions:
+                if divisions == self.divisions:
+                    # noop
+                    return self
+                new_divisions = divisions
+            elif npartitions:
+                rows_per_partition = math.ceil(nrows / npartitions)
+            if rows_per_partition:
+                new_divs = list(range(0, nrows, rows_per_partition))
+                new_divs.append(nrows)
+                new_divisions = tuple(new_divs)
+            token = tokenize(self, divisions)
+            key = f"repartition-{token}"
+            new_layer_raw = repartition_layer(self, key, new_divisions)
+
         new_layer = AwkwardMaterializedLayer(
             new_layer_raw,
             previous_layer_names=[self.name],
diff --git a/src/dask_awkward/lib/structure.py b/src/dask_awkward/lib/structure.py
index ae5f104f..84b5ea8a 100644
--- a/src/dask_awkward/lib/structure.py
+++ b/src/dask_awkward/lib/structure.py
@@ -1350,6 +1350,49 @@ def repartition_layer(arr: Array, key: str, divisions: tuple[int, ...]) -> dict:
     return layer
 
 
+def _subpart(data: ak.Array, parts: int, part: int) -> ak.Array:
+    from dask_awkward.lib.core import is_typetracer
+
+    if is_typetracer(data):
+        return data
+    rows_per = len(data) // parts
+    return data[
+        part * rows_per : None if part == (parts - 1) else (part + 1) * rows_per
+    ]
+
+
+def _subcat(*arrs: tuple[ak.Array, ...]) -> ak.Array:
+    return ak.concatenate(arrs)
+
+
+def simple_repartition_layer(
+    arr: Array, n_to_one: int | None, one_to_n: int | None, key: str
+) -> tuple[dict, tuple[Any, ...]]:
+    layer: dict[tuple[str, int], tuple[Any, ...]] = {}
+    new_divisions: tuple[Any, ...]
+    if n_to_one:
+        for i in range(0, arr.npartitions, n_to_one):
+            layer[(key, i)] = (_subcat,) + tuple(
+                (arr.name, part)
+                for part in range(i, min(i + n_to_one, arr.npartitions))
+            )
+        new_divisions = arr.divisions[::n_to_one]
+    elif one_to_n:
+        for i in range(arr.npartitions):
+            for part in range(one_to_n):
+                layer[(key, (i * one_to_n + part))] = (
+                    _subpart,
+                    (arr.name, i),
+                    one_to_n,
+                    part,
+                )
+        # TODO: if arr.known_divisions:
+        new_divisions = (None,) * (arr.npartitions * one_to_n + 1)
+    else:
+        raise ValueError
+    return layer, new_divisions
+
+
 @borrow_docstring(ak.enforce_type)
 def enforce_type(
     array: Array,
diff --git a/tests/test_structure.py b/tests/test_structure.py
index d196ee35..3c9b1673 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -539,6 +539,12 @@ def test_repartition_whole(daa):
     assert_eq(daa, daa1, check_divisions=False)
 
 
+def test_repartition_one_to_n(daa):
+    daa1 = daa.repartition(one_to_n=2)
+    assert daa1.npartitions == daa.npartitions * 2
+    assert_eq(daa, daa1, check_divisions=False)
+
+
 def test_repartition_no_change(daa):
     daa1 = daa.repartition(divisions=(0, 5, 10, 15))
     assert daa1.npartitions == 3

From 3ff54e57f3c4a426d4a4d197d677c4bddd1c3068 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 17 Jun 2024 21:44:28 +0000
Subject: [PATCH 10/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.8 → v0.4.9](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.8...v0.4.9)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index cf0308b5..4c06f6eb 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.8
+  rev: v0.4.9
   hooks:
   - id: ruff
 

From c492ac42fee1c17f46501d93305a637649d5a6bf Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 09:29:34 -0400
Subject: [PATCH 11/22] Respect inverse in scalar binop

---
 src/dask_awkward/lib/core.py | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/src/dask_awkward/lib/core.py b/src/dask_awkward/lib/core.py
index 204ccc3f..e52e43af 100644
--- a/src/dask_awkward/lib/core.py
+++ b/src/dask_awkward/lib/core.py
@@ -502,9 +502,17 @@ def f(self, other):
             if is_dask_collection(other):
                 task = (op, self.key, *other.__dask_keys__())
                 deps.append(other)
-                plns.append(other.name)
+                if inv:
+                    plns.insert(0, other.name)
+                else:
+                    plns.append(other.name)
             else:
-                task = (op, self.key, other)
+                if inv:
+                    task = (op, other, self.key)
+                else:
+                    task = (op, self.key, other)
+            if inv:
+                plns.reverse()
             graph = HighLevelGraph.from_collections(
                 name,
                 layer=AwkwardMaterializedLayer(
@@ -514,10 +522,16 @@ def f(self, other):
                 ),
                 dependencies=tuple(deps),
             )
-            if isinstance(other, Scalar):
-                meta = op(self._meta, other._meta)
+            if isinstance(other, (Scalar, Array)):
+                if inv:
+                    meta = op(other._meta, self._meta)
+                else:
+                    meta = op(self._meta, other._meta)
             else:
-                meta = op(self._meta, other)
+                if inv:
+                    meta = op(other, self._meta)
+                else:
+                    meta = op(self._meta, other)
             return new_scalar_object(graph, name, meta=meta)
 
         return f

From 46b0a9f2bdeea7d4fc3c789ee753c2128fb6ea70 Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 09:34:30 -0400
Subject: [PATCH 12/22] Add test

---
 tests/test_core.py | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/tests/test_core.py b/tests/test_core.py
index 369cdbb4..8dd82b9f 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -115,7 +115,7 @@ def test_len(ndjson_points_file: str) -> None:
         assert len(daa) == 10
     daa.eager_compute_divisions()
     assert daa.known_divisions
-    assert len(daa) == 10  # type: ignore
+    assert len(daa) == 10
 
 
 def test_meta_exists(daa: Array) -> None:
@@ -157,7 +157,7 @@ def test_partitions_divisions(ndjson_points_file: str) -> None:
     assert not t1.known_divisions
     t2 = daa.partitions[1]
     assert t2.known_divisions
-    assert t2.divisions == (0, divs[2] - divs[1])  # type: ignore
+    assert t2.divisions == (0, divs[2] - divs[1])
 
 
 def test_array_rebuild(ndjson_points_file: str) -> None:
@@ -537,7 +537,7 @@ def test_compatible_partitions_after_slice() -> None:
     assert_eq(lazy, ccrt)
 
     # sanity
-    assert dak.compatible_partitions(lazy, lazy + 2)  # type: ignore
+    assert dak.compatible_partitions(lazy, lazy + 2)
     assert dak.compatible_partitions(lazy, dak.num(lazy, axis=1) > 2)
 
     assert not dak.compatible_partitions(lazy[:-2], lazy)
@@ -646,6 +646,14 @@ def test_scalar_divisions(daa: Array) -> None:
     assert s.divisions == (None, None)
 
 
+def test_scalar_binop_inv() -> None:
+    # GH #515
+    x = dak.from_lists([[1]])
+    y = x[0]  # scalar
+    assert (0 - y) == -1
+    assert (y - 0) == 1
+
+
 def test_array_persist(daa: Array) -> None:
     daa2 = daa["points"]["x"].persist()
     assert_eq(daa["points"]["x"], daa2)
@@ -886,7 +894,7 @@ def test_shape_only_ops(fn: Callable, tmp_path_factory: pytest.TempPathFactory)
     p = tmp_path_factory.mktemp("zeros-like-flat")
     ak.to_parquet(a, str(p / "file.parquet"))
     lazy = dak.from_parquet(str(p))
-    result = fn(lazy.b)  # type: ignore
+    result = fn(lazy.b)
     with dask.config.set({"awkward.optimization.enabled": True}):
         result.compute()
 
@@ -898,7 +906,7 @@ def test_assign_behavior() -> None:
     with pytest.raises(
         TypeError, match="'mappingproxy' object does not support item assignment"
     ):
-        dx.behavior["should_fail"] = None  # type: ignore
+        dx.behavior["should_fail"] = None
     assert dx.behavior == behavior
 
 
@@ -909,7 +917,7 @@ def test_assign_attrs() -> None:
     with pytest.raises(
         TypeError, match="'mappingproxy' object does not support item assignment"
     ):
-        dx.attrs["should_fail"] = None  # type: ignore
+        dx.attrs["should_fail"] = None
     assert dx.attrs == attrs
 
 

From ca75020a9fddae210bde5422bf6e6d4e5b426dda Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 09:44:04 -0400
Subject: [PATCH 13/22] no mypy for test files

---
 pyproject.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 56ab6f1e..7527ba14 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -111,7 +111,7 @@ src_paths = ["src", "tests"]
 
 [tool.mypy]
 python_version = "3.9"
-files = ["src", "tests"]
+files = ["src"]
 strict = false
 warn_unused_configs = true
 show_error_codes = true

From 442d44136a9f56a05197f628c0ff22fac3c96685 Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 10:22:45 -0400
Subject: [PATCH 14/22] Don't mypy tests (again)

---
 .pre-commit-config.yaml | 1 +
 pyproject.toml          | 1 +
 2 files changed, 2 insertions(+)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 4c06f6eb..226b54f1 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -62,6 +62,7 @@ repos:
   rev: v1.10.0
   hooks:
   - id: mypy
+    files: "src/"
     args: [--ignore-missing-imports]
     additional_dependencies:
     - dask
diff --git a/pyproject.toml b/pyproject.toml
index 7527ba14..4bbafc23 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -112,6 +112,7 @@ src_paths = ["src", "tests"]
 [tool.mypy]
 python_version = "3.9"
 files = ["src"]
+exclude = ["tests/"]
 strict = false
 warn_unused_configs = true
 show_error_codes = true

From 0803b43a1a545d9e383d3c6a7764f75a9d6d930d Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 10:36:03 -0400
Subject: [PATCH 15/22] Fix n_to_one repartition

---
 src/dask_awkward/lib/structure.py |  9 +++++++--
 tests/test_structure.py           | 13 +++++++++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/dask_awkward/lib/structure.py b/src/dask_awkward/lib/structure.py
index 7afba822..af72d527 100644
--- a/src/dask_awkward/lib/structure.py
+++ b/src/dask_awkward/lib/structure.py
@@ -1412,12 +1412,17 @@ def simple_repartition_layer(
     layer: dict[tuple[str, int], tuple[Any, ...]] = {}
     new_divisions: tuple[Any, ...]
     if n_to_one:
-        for i in range(0, arr.npartitions, n_to_one):
-            layer[(key, i)] = (_subcat,) + tuple(
+        for i0, i in enumerate(range(0, arr.npartitions, n_to_one)):
+            layer[(key, i0)] = (_subcat,) + tuple(
                 (arr.name, part)
                 for part in range(i, min(i + n_to_one, arr.npartitions))
             )
         new_divisions = arr.divisions[::n_to_one]
+        if arr.npartitions % n_to_one:
+            new_divisions = new_divisions + (arr.divisions[-1],)
+            layer[(key, i0 + 1)] = (_subcat,) + tuple(
+                (arr.name, part) for part in range(new_divisions[-2], new_divisions[-1])
+            )
     elif one_to_n:
         for i in range(arr.npartitions):
             for part in range(one_to_n):
diff --git a/tests/test_structure.py b/tests/test_structure.py
index 8e003d97..22a3d500 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -554,6 +554,19 @@ def test_repartition_one_to_n(daa):
     assert_eq(daa, daa1, check_divisions=False)
 
 
+def test_repartition_n_to_one():
+    daa = dak.from_lists([[[1, 2, 3], [], [4, 5]]] * 52)
+    daa2 = daa.repartition(n_to_one=52)
+    assert daa2.npartitions == 1
+    assert daa.compute().to_list() == daa2.compute().to_list()
+    daa2 = daa.repartition(n_to_one=53)
+    assert daa2.npartitions == 1
+    assert daa.compute().to_list() == daa2.compute().to_list()
+    daa2 = daa.repartition(n_to_one=2)
+    assert daa2.npartitions == 26
+    assert daa.compute().to_list() == daa2.compute().to_list()
+
+
 def test_repartition_no_change(daa):
     daa1 = daa.repartition(divisions=(0, 5, 10, 15))
     assert daa1.npartitions == 3

From 5a0af7b9f4f82470c66534f4313e4511960e754b Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 10:38:06 -0400
Subject: [PATCH 16/22] test unever case

---
 tests/test_structure.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tests/test_structure.py b/tests/test_structure.py
index 22a3d500..9b761339 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -565,6 +565,9 @@ def test_repartition_n_to_one():
     daa2 = daa.repartition(n_to_one=2)
     assert daa2.npartitions == 26
     assert daa.compute().to_list() == daa2.compute().to_list()
+    daa2 = daa.repartition(n_to_one=10)
+    assert daa2.npartitions == 6
+    assert daa.compute().to_list() == daa2.compute().to_list()
 
 
 def test_repartition_no_change(daa):

From 188483e80810e28f567888d44a358b68f894792e Mon Sep 17 00:00:00 2001
From: Martin Durant <martin.durant@alumni.utoronto.ca>
Date: Wed, 19 Jun 2024 11:09:42 -0400
Subject: [PATCH 17/22] fix: allow for Nones in repartition n_to_one

---
 src/dask_awkward/lib/structure.py | 2 +-
 tests/test_structure.py           | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/dask_awkward/lib/structure.py b/src/dask_awkward/lib/structure.py
index af72d527..6b70c8b9 100644
--- a/src/dask_awkward/lib/structure.py
+++ b/src/dask_awkward/lib/structure.py
@@ -1421,7 +1421,7 @@ def simple_repartition_layer(
         if arr.npartitions % n_to_one:
             new_divisions = new_divisions + (arr.divisions[-1],)
             layer[(key, i0 + 1)] = (_subcat,) + tuple(
-                (arr.name, part) for part in range(new_divisions[-2], new_divisions[-1])
+                (arr.name, part0) for part0 in range(len(layer), arr.npartitions)
             )
     elif one_to_n:
         for i in range(arr.npartitions):
diff --git a/tests/test_structure.py b/tests/test_structure.py
index 9b761339..9f86b747 100644
--- a/tests/test_structure.py
+++ b/tests/test_structure.py
@@ -555,7 +555,7 @@ def test_repartition_one_to_n(daa):
 
 
 def test_repartition_n_to_one():
-    daa = dak.from_lists([[[1, 2, 3], [], [4, 5]]] * 52)
+    daa = dak.from_lists([[[1, 2, 3], [], [4, 5]] * 2] * 52)
     daa2 = daa.repartition(n_to_one=52)
     assert daa2.npartitions == 1
     assert daa.compute().to_list() == daa2.compute().to_list()
@@ -568,6 +568,9 @@ def test_repartition_n_to_one():
     daa2 = daa.repartition(n_to_one=10)
     assert daa2.npartitions == 6
     assert daa.compute().to_list() == daa2.compute().to_list()
+    daa._divisions = (None,) * len(daa.divisions)
+    assert daa2.npartitions == 6
+    assert daa.compute().to_list() == daa2.compute().to_list()
 
 
 def test_repartition_no_change(daa):

From 3e3c884a6fdb762f36eb3716629f51132abd2148 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 24 Jun 2024 21:37:05 +0000
Subject: [PATCH 18/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.9 → v0.4.10](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.9...v0.4.10)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 226b54f1..4de485d5 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.9
+  rev: v0.4.10
   hooks:
   - id: ruff
 

From ebe17fd5ddc6204ac4e64b09b63eecafb58ac6f5 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 1 Jul 2024 23:17:05 +0000
Subject: [PATCH 19/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.4.10 → v0.5.0](https://github.com/astral-sh/ruff-pre-commit/compare/v0.4.10...v0.5.0)
- [github.com/adamchainz/blacken-docs: 1.16.0 → 1.18.0](https://github.com/adamchainz/blacken-docs/compare/1.16.0...1.18.0)
- [github.com/pre-commit/mirrors-mypy: v1.10.0 → v1.10.1](https://github.com/pre-commit/mirrors-mypy/compare/v1.10.0...v1.10.1)
---
 .pre-commit-config.yaml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 4de485d5..7984064c 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.4.10
+  rev: v0.5.0
   hooks:
   - id: ruff
 
@@ -52,14 +52,14 @@ repos:
   - id: yesqa
 
 - repo: https://github.com/adamchainz/blacken-docs
-  rev: 1.16.0
+  rev: 1.18.0
   hooks:
   - id: blacken-docs
     additional_dependencies:
     - black
 
 - repo: https://github.com/pre-commit/mirrors-mypy
-  rev: v1.10.0
+  rev: v1.10.1
   hooks:
   - id: mypy
     files: "src/"

From 49bf2d792442cf8bae065271c18022bf3813be37 Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 8 Jul 2024 21:16:43 +0000
Subject: [PATCH 20/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.5.0 → v0.5.1](https://github.com/astral-sh/ruff-pre-commit/compare/v0.5.0...v0.5.1)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 7984064c..e76d580a 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.5.0
+  rev: v0.5.1
   hooks:
   - id: ruff
 

From 77ccde61ed82a037691c5ab48dc3c78fa04dc89d Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 15 Jul 2024 21:48:38 +0000
Subject: [PATCH 21/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.5.1 → v0.5.2](https://github.com/astral-sh/ruff-pre-commit/compare/v0.5.1...v0.5.2)
---
 .pre-commit-config.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index e76d580a..b35527a1 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.5.1
+  rev: v0.5.2
   hooks:
   - id: ruff
 

From 295748899abd7a8659b426236dc0b94917c3d85e Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Mon, 22 Jul 2024 21:51:46 +0000
Subject: [PATCH 22/22] [pre-commit.ci] pre-commit autoupdate
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.5.2 → v0.5.4](https://github.com/astral-sh/ruff-pre-commit/compare/v0.5.2...v0.5.4)
- [github.com/pre-commit/mirrors-mypy: v1.10.1 → v1.11.0](https://github.com/pre-commit/mirrors-mypy/compare/v1.10.1...v1.11.0)
---
 .pre-commit-config.yaml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index b35527a1..2db13547 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
     - --target-version=py312
 
 - repo: https://github.com/astral-sh/ruff-pre-commit
-  rev: v0.5.2
+  rev: v0.5.4
   hooks:
   - id: ruff
 
@@ -59,7 +59,7 @@ repos:
     - black
 
 - repo: https://github.com/pre-commit/mirrors-mypy
-  rev: v1.10.1
+  rev: v1.11.0
   hooks:
   - id: mypy
     files: "src/"