poc: extend exists/2 to traverse embedded array attributes

lib/data_layer.ex

@@ -731,6 +731,7 @@ defmodule AshPostgres.DataLayer do
 
   def can?(_, {:aggregate, :unrelated}), do: true
   def can?(_, {:exists, :unrelated}), do: true
+  def can?(_, {:exists, :embedded_array}), do: true
   def can?(_, :aggregate_filter), do: true
   def can?(_, :aggregate_sort), do: true
   def can?(_, :calculate), do: true

priv/resource_snapshots/test_repo/embedded_array_companies/20260516132942.json

@@ -0,0 +1,44 @@
+{
+  "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"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "create_table_options": null,
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "76AC03FB2DBC3C968CBC922C933E82F084A07AFD4FBE6C90BBE53E5E755BC37F",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "embedded_array_companies"
+}

priv/resource_snapshots/test_repo/embedded_array_estimates/20260515050043.json

@@ -0,0 +1,68 @@
+{
+  "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": "title",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "true",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "active",
+      "type": "boolean"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "options",
+      "type": "jsonb"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "create_table_options": null,
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "7E03C1BEBCCEE486DAB75FCA9D4BA7454F6C120C032ABB5C08398C120196EFC2",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "embedded_array_estimates"
+}

priv/resource_snapshots/test_repo/embedded_array_estimates/20260516132943.json

@@ -0,0 +1,99 @@
+{
+  "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": "title",
+      "type": "text"
+    },
+    {
+      "allow_nil?": true,
+      "default": "true",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "active",
+      "type": "boolean"
+    },
+    {
+      "allow_nil?": true,
+      "default": "nil",
+      "generated?": false,
+      "precision": null,
+      "primary_key?": false,
+      "references": null,
+      "scale": null,
+      "size": null,
+      "source": "options",
+      "type": "jsonb"
+    },
+    {
+      "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": "embedded_array_estimates_company_id_fkey",
+        "on_delete": null,
+        "on_update": null,
+        "primary_key?": true,
+        "schema": "public",
+        "table": "embedded_array_companies"
+      },
+      "scale": null,
+      "size": null,
+      "source": "company_id",
+      "type": "uuid"
+    }
+  ],
+  "base_filter": null,
+  "check_constraints": [],
+  "create_table_options": null,
+  "custom_indexes": [],
+  "custom_statements": [],
+  "has_create_action": true,
+  "hash": "29C7F9D1AA3AFAEA997BBBD762FBDA7486336DCBFFBC4A065C45B6DE34DB1707",
+  "identities": [],
+  "multitenancy": {
+    "attribute": null,
+    "global": null,
+    "strategy": null
+  },
+  "repo": "Elixir.AshPostgres.TestRepo",
+  "schema": null,
+  "table": "embedded_array_estimates"
+}

priv/test_repo/migrations/20260515050043_migrate_resources68.exs

@@ -0,0 +1,22 @@
+defmodule AshPostgres.TestRepo.Migrations.MigrateResources68 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(:embedded_array_estimates, primary_key: false) do
+      add(:id, :uuid, null: false, default: fragment("gen_random_uuid()"), primary_key: true)
+      add(:title, :text)
+      add(:active, :boolean, default: true)
+      add(:options, :jsonb)
+    end
+  end
+
+  def down do
+    drop(table(:embedded_array_estimates))
+  end
+end

priv/test_repo/migrations/20260516132941_migrate_resources71.exs

@@ -0,0 +1,29 @@
+defmodule AshPostgres.TestRepo.Migrations.MigrateResources71 do
+  @moduledoc """
+  Adds the `embedded_array_companies` table and the `company_id` column on
+  `embedded_array_estimates`. Other autogenerated changes for unrelated
+  resources (interest/profile_interest schemas, classroom.public) were
+  trimmed out because those tables already exist in the local test DB.
+  """
+
+  use Ecto.Migration
+
+  def up do
+    alter table(:embedded_array_estimates) do
+      add(:company_id, :uuid)
+    end
+
+    create table(:embedded_array_companies, primary_key: false) do
+      add(:id, :uuid, null: false, default: fragment("gen_random_uuid()"), primary_key: true)
+      add(:name, :text)
+    end
+  end
+
+  def down do
+    drop(table(:embedded_array_companies))
+
+    alter table(:embedded_array_estimates) do
+      remove(:company_id)
+    end
+  end
+end