test: reproduce a bug with a complex calculation (#593)

* reproduce a bug with a complex calculation

* no unused vars

Author: jsw800

priv/resource_snapshots/test_repo/complex_calculations_folder_items/20250714225304.json

@@ -0,0 +1,86 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"gen_random_uuid()\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": true,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "name",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "level",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": {
+        "deferrable": false,
+        "destination_attribute": "id",
+        "destination_attribute_default": null,
+        "destination_attribute_generated": null,
+        "index?": false,
+        "match_type": null,
+        "match_with": null,
+        "multitenancy": {
+          "attribute": null,
+          "global": null,
+          "strategy": null
+        },
+        "name": "complex_calculations_folder_items_folder_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "complex_calculations_folders"
+      },
+      "scale": null,
+      "size": null,
+      "source": "folder_id",
+      "type": "uuid"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": false,
+  "hash": "C7BC97676F202A744482B4095560986B265E6BCB74F6E69C1330034FBC4981E5",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "complex_calculations_folder_items"
+}

priv/resource_snapshots/test_repo/complex_calculations_folders/20250714225304.json

@@ -0,0 +1,55 @@
+{
+  "attributes": [
+    {
+      "allow_nil?": false,
+      "default": "fragment(\"gen_random_uuid()\")",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": true,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "id",
+      "type": "uuid"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "some_integer_setting",
+      "type": "bigint"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "level",
+      "type": "ltree"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": false,
+  "hash": "1982E0DAF0B5B22502A5747ED8533C6F1D58E882E1132FAB0939EC13F2CFC5AF",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "complex_calculations_folders"
+}

priv/test_repo/migrations/20250714225304_add_complex_calculations_folder_and_items.exs

@@ -0,0 +1,61 @@
+defmodule AshPostgres.TestRepo.Migrations.AddComplexCalculationsFolderAndItems do
+  @moduledoc """
+  Updates resources based on their most recent snapshots.
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    create table(:complex_calculations_folder_items, primary_key: false) do
+      add(:id, :uuid, null: false, default: fragment("gen_random_uuid()"), primary_key: true)
+      add(:name, :text)
+      add(:level, :bigint)
+      add(:folder_id, :uuid)
+    end
+
+    create table(:complex_calculations_folders, primary_key: false) do
+      add(:id, :uuid, null: false, default: fragment("gen_random_uuid()"), primary_key: true)
+    end
+
+    alter table(:complex_calculations_folder_items) do
+      modify(
+        :folder_id,
+        references(:complex_calculations_folders,
+          column: :id,
+          name: "complex_calculations_folder_items_folder_id_fkey",
+          type: :uuid,
+          prefix: "public"
+        )
+      )
+    end
+
+    alter table(:complex_calculations_folders) do
+      add(:some_integer_setting, :bigint)
+      add(:level, :ltree)
+    end
+  end
+
+  def down do
+    alter table(:complex_calculations_folders) do
+      remove(:level)
+      remove(:some_integer_setting)
+    end
+
+    drop(
+      constraint(
+        :complex_calculations_folder_items,
+        "complex_calculations_folder_items_folder_id_fkey"
+      )
+    )
+
+    alter table(:complex_calculations_folder_items) do
+      modify(:folder_id, :uuid)
+    end
+
+    drop(table(:complex_calculations_folders))
+
+    drop(table(:complex_calculations_folder_items))
+  end
+end

test/complex_calculations_test.exs

@@ -373,4 +373,34 @@ defmodule AshPostgres.Test.ComplexCalculationsTest do
     assert doc_before.is_active_with_timezone == false
     assert doc_after.is_active_with_timezone == true
   end
+
+  test "gnarly parent bug with some weird ltree setup" do
+    _folder_a =
+      Ash.Seed.seed!(
+        AshPostgres.Test.Support.ComplexCalculations.Folder,
+        %{some_integer_setting: 1, level: "a"}
+      )
+
+    _folder_b =
+      Ash.Seed.seed!(
+        AshPostgres.Test.Support.ComplexCalculations.Folder,
+        %{some_integer_setting: nil, level: "a.b"}
+      )
+
+    folder_c =
+      Ash.Seed.seed!(
+        AshPostgres.Test.Support.ComplexCalculations.Folder,
+        %{some_integer_setting: nil, level: "a.b.c"}
+      )
+
+    folder_c_item =
+      Ash.Seed.seed!(
+        AshPostgres.Test.Support.ComplexCalculations.FolderItem,
+        %{name: "Item in C", level: 1, folder_id: folder_c.id}
+      )
+
+    # reproduction: this raises Unknown Error
+    # * ** (Postgrex.Error) ERROR 42846 (cannot_coerce) cannot cast type bigint to ltree
+    assert Ash.calculate!(folder_c_item, :folder_setting) == 1
+  end
 end

test/support/complex_calculations/domain.ex

@@ -9,6 +9,8 @@ defmodule AshPostgres.Test.ComplexCalculations.Domain do
     resource(AshPostgres.Test.ComplexCalculations.Channel)
     resource(AshPostgres.Test.ComplexCalculations.DMChannel)
     resource(AshPostgres.Test.ComplexCalculations.ChannelMember)
+    resource(AshPostgres.Test.Support.ComplexCalculations.Folder)
+    resource(AshPostgres.Test.Support.ComplexCalculations.FolderItem)
   end
 
   authorization do

test/support/complex_calculations/resources/folder.ex

@@ -0,0 +1,75 @@
+defmodule AshPostgres.Test.Support.ComplexCalculations.Folder do
+  @moduledoc """
+  A tree structure using the ltree type.
+  """
+
+  alias AshPostgres.Test.Support.ComplexCalculations.Folder
+
+  use Ash.Resource,
+    domain: AshPostgres.Test.ComplexCalculations.Domain,
+    data_layer: AshPostgres.DataLayer
+
+  @default_integer_setting 5
+
+  postgres do
+    table "complex_calculations_folders"
+    repo(AshPostgres.TestRepo)
+  end
+
+  attributes do
+    uuid_primary_key(:id)
+
+    attribute(:some_integer_setting, :integer,
+      public?: true,
+      description: "Some setting that can be inherited. No real semantic meaning, just for demo"
+    )
+
+    attribute(:level, AshPostgres.Ltree, public?: true)
+  end
+
+  actions do
+    defaults([:read])
+  end
+
+  relationships do
+    has_many :ancestors, Folder do
+      public?(true)
+      no_attributes?(true)
+
+      # use ltree @> operator to get all ancestors
+      filter(expr(fragment("? @> ? AND ? < ?", level, parent(level), nlevel, parent(nlevel))))
+    end
+
+    has_many :items, AshPostgres.Test.Support.ComplexCalculations.FolderItem do
+      public?(true)
+    end
+  end
+
+  calculations do
+    calculate(:nlevel, :integer, expr(fragment("nlevel(?)", level)))
+
+    calculate(
+      :effective_integer_setting,
+      :integer,
+      expr(
+        if is_nil(some_integer_setting) do
+          # closest ancestor with a non-nil setting, or the default
+          first(
+            ancestors,
+            query: [
+              sort: [nlevel: :desc],
+              filter: expr(not is_nil(some_integer_setting))
+            ],
+            field: :some_integer_setting
+          ) || @default_integer_setting
+        else
+          some_integer_setting
+        end
+      ),
+      description: """
+      The effective integer setting, inheriting from ancestors if not explicitly set,
+      or defaulting to #{@default_integer_setting} if none are set. No real semantic meaning, just for demo
+      """
+    )
+  end
+end

test/support/complex_calculations/resources/folder_item.ex

@@ -0,0 +1,38 @@
+defmodule AshPostgres.Test.Support.ComplexCalculations.FolderItem do
+  @moduledoc false
+  use Ash.Resource,
+    domain: AshPostgres.Test.ComplexCalculations.Domain,
+    data_layer: AshPostgres.DataLayer
+
+  postgres do
+    table "complex_calculations_folder_items"
+    repo(AshPostgres.TestRepo)
+  end
+
+  attributes do
+    uuid_primary_key(:id)
+    attribute(:name, :string, public?: true)
+
+    attribute(:level, :integer,
+      public?: true,
+      description: """
+      No real semantic meaning here, just for demo, this *deliberately* is named the same as the ltree level column in Folder,
+      but is NOT related to it in any way
+      """
+    )
+  end
+
+  actions do
+    defaults([:read])
+  end
+
+  calculations do
+    calculate(:folder_setting, :integer, expr(folder.effective_integer_setting))
+  end
+
+  relationships do
+    belongs_to(:folder, AshPostgres.Test.Support.ComplexCalculations.Folder) do
+      public?(true)
+    end
+  end
+end