Add comprehensive tests for Accounts.UserCredential

Improved coverage from 28.57% to 100% by adding 13 tests covering:
- Required field validations (user_id, credential_id, public_key, name)
- Name length validation (min 1, max 100 characters)
- Optional field handling (sign_count, last_used_at, aaguid, transports, backup flags, attestation_format)
- Default values for optional fields
- touch_changeset/1 function (updates last_used_at and increments sign_count)

Overall coverage: 66.44%

test/towerops/accounts/user_credential_test.exs

@@ -0,0 +1,200 @@
+defmodule Towerops.Accounts.UserCredentialTest do
+  use Towerops.DataCase
+
+  alias Towerops.Accounts.UserCredential
+
+  describe "changeset/2" do
+    test "valid changeset with required fields" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: "My Passkey"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      assert changeset.valid?
+      assert get_field(changeset, :name) == "My Passkey"
+      assert get_field(changeset, :credential_id) == attrs.credential_id
+      assert get_field(changeset, :public_key) == attrs.public_key
+    end
+
+    test "requires user_id" do
+      attrs = %{
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: "My Passkey"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      assert %{user_id: ["can't be blank"]} = errors_on(changeset)
+    end
+
+    test "requires credential_id" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: "My Passkey"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      assert %{credential_id: ["can't be blank"]} = errors_on(changeset)
+    end
+
+    test "requires public_key" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        name: "My Passkey"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      assert %{public_key: ["can't be blank"]} = errors_on(changeset)
+    end
+
+    test "requires name" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65)
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      assert %{name: ["can't be blank"]} = errors_on(changeset)
+    end
+
+    test "validates name length minimum" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: ""
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      # Empty string triggers "can't be blank" before length validation
+      assert %{name: ["can't be blank"]} = errors_on(changeset)
+    end
+
+    test "validates name length maximum" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: String.duplicate("a", 101)
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      refute changeset.valid?
+      assert %{name: ["should be at most 100 character(s)"]} = errors_on(changeset)
+    end
+
+    test "accepts name at maximum length" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: String.duplicate("a", 100)
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      assert changeset.valid?
+    end
+
+    test "accepts optional fields" do
+      last_used_at = DateTime.truncate(DateTime.utc_now(), :second)
+
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: "My Passkey",
+        sign_count: 42,
+        last_used_at: last_used_at,
+        aaguid: :crypto.strong_rand_bytes(16),
+        transports: ["usb", "nfc"],
+        backup_eligible: true,
+        backup_state: true,
+        attestation_format: "packed"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      assert changeset.valid?
+      assert get_field(changeset, :sign_count) == 42
+      assert DateTime.compare(get_field(changeset, :last_used_at), last_used_at) == :eq
+      assert get_field(changeset, :aaguid) == attrs.aaguid
+      assert get_field(changeset, :transports) == ["usb", "nfc"]
+      assert get_field(changeset, :backup_eligible) == true
+      assert get_field(changeset, :backup_state) == true
+      assert get_field(changeset, :attestation_format) == "packed"
+    end
+
+    test "uses default values for optional fields when not provided" do
+      attrs = %{
+        user_id: Ecto.UUID.generate(),
+        credential_id: :crypto.strong_rand_bytes(16),
+        public_key: :crypto.strong_rand_bytes(65),
+        name: "My Passkey"
+      }
+
+      changeset = UserCredential.changeset(%UserCredential{}, attrs)
+
+      assert changeset.valid?
+      # These defaults come from the schema definition
+      assert get_field(changeset, :sign_count) == 0
+      assert get_field(changeset, :transports) == []
+      assert get_field(changeset, :backup_eligible) == false
+      assert get_field(changeset, :backup_state) == false
+    end
+  end
+
+  describe "touch_changeset/1" do
+    test "updates last_used_at to current time" do
+      old_time = DateTime.add(DateTime.utc_now(), -3600, :second)
+
+      credential = %UserCredential{
+        sign_count: 5,
+        last_used_at: old_time
+      }
+
+      changeset = UserCredential.touch_changeset(credential)
+      last_used_at = get_field(changeset, :last_used_at)
+
+      # Should be more recent than the old time
+      assert DateTime.after?(last_used_at, old_time)
+      # Should be within last 2 seconds (account for timing + truncation)
+      diff = DateTime.diff(DateTime.utc_now(), last_used_at, :second)
+      assert diff <= 2
+    end
+
+    test "increments sign_count by 1" do
+      credential = %UserCredential{sign_count: 5}
+
+      changeset = UserCredential.touch_changeset(credential)
+
+      assert get_field(changeset, :sign_count) == 6
+    end
+
+    test "increments sign_count from 0" do
+      credential = %UserCredential{sign_count: 0}
+
+      changeset = UserCredential.touch_changeset(credential)
+
+      assert get_field(changeset, :sign_count) == 1
+    end
+  end
+end