From 8f130a7598d2030b30617c5929504d074fad12b0 Mon Sep 17 00:00:00 2001
From: shibao <shibao@bubbletea.dev>
Date: Mon, 31 Jan 2022 23:45:00 -0500
Subject: [PATCH] add types to ecto changeset specs

---
 CONTRIBUTING.md                         |  2 +-
 lib/cannery/accounts.ex                 | 20 +++++++++++---------
 lib/cannery/accounts/user.ex            | 24 +++++++++++++-----------
 lib/cannery/ammo.ex                     | 22 ++++++++++++++--------
 lib/cannery/ammo/ammo_group.ex          |  2 +-
 lib/cannery/ammo/ammo_type.ex           |  2 +-
 lib/cannery/containers.ex               | 18 ++++++++++--------
 lib/cannery/containers/container.ex     |  2 +-
 lib/cannery/containers/container_tag.ex |  3 ++-
 lib/cannery/invites.ex                  | 22 ++++++++++++----------
 lib/cannery/invites/invite.ex           |  2 +-
 lib/cannery/tags.ex                     | 11 ++++++-----
 lib/cannery/tags/tag.ex                 |  2 +-
 13 files changed, 74 insertions(+), 58 deletions(-)

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 4cd291ca..f3756ece 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -9,7 +9,7 @@ contributing to Cannery (hopefully) as great of an experience as you found it!
   inline `do:` blocks for short functions and make your aliases as short as
   possible without introducing ambiguity.
   - I.e. since there's only one `Changeset` in the app, please alias
-    `Changeset.t()` instead of using `Ecto.Changeset.t()`
+    `Changeset.t(Type.t())` instead of using `Ecto.Changeset.t(Long.Type.t())`
 - Use pipelines when possible. If a function only calls a single method, a
   pipeline isn't strictly necessary but still encouraged for future
   modification.
diff --git a/lib/cannery/accounts.ex b/lib/cannery/accounts.ex
index 130415b2..a1b1f064 100644
--- a/lib/cannery/accounts.ex
+++ b/lib/cannery/accounts.ex
@@ -89,7 +89,7 @@ defmodule Cannery.Accounts do
       {:error, %Changeset{}}
 
   """
-  @spec register_user(map()) :: {:ok, User.t()} | {:error, Changeset.t()}
+  @spec register_user(map()) :: {:ok, User.t()} | {:error, Changeset.t(User.new_user())}
   def register_user(attrs) do
     # if no registered users, make first user an admin
     attrs =
@@ -109,8 +109,10 @@ defmodule Cannery.Accounts do
       %Changeset{data: %User{}}
 
   """
-  @spec change_user_registration(User.t() | User.new_user()) :: Changeset.t()
-  @spec change_user_registration(User.t() | User.new_user(), map()) :: Changeset.t()
+  @spec change_user_registration(User.t() | User.new_user()) ::
+          Changeset.t(User.t() | User.new_user())
+  @spec change_user_registration(User.t() | User.new_user(), map()) ::
+          Changeset.t(User.t() | User.new_user())
   def change_user_registration(user, attrs \\ %{}),
     do: User.registration_changeset(user, attrs, hash_password: false)
 
@@ -125,7 +127,7 @@ defmodule Cannery.Accounts do
       %Changeset{data: %User{}}
 
   """
-  @spec change_user_email(User.t(), map()) :: Changeset.t()
+  @spec change_user_email(User.t(), map()) :: Changeset.t(User.t())
   def change_user_email(user, attrs \\ %{}), do: User.email_changeset(user, attrs)
 
   @doc """
@@ -137,7 +139,7 @@ defmodule Cannery.Accounts do
       %Changeset{data: %User{}}
 
   """
-  @spec change_user_role(User.t(), atom()) :: Changeset.t()
+  @spec change_user_role(User.t(), atom()) :: Changeset.t(User.t())
   def change_user_role(user, role), do: User.role_changeset(user, role)
 
   @doc """
@@ -154,7 +156,7 @@ defmodule Cannery.Accounts do
 
   """
   @spec apply_user_email(User.t(), String.t(), map()) ::
-          {:ok, User.t()} | {:error, Changeset.t()}
+          {:ok, User.t()} | {:error, Changeset.t(User.t())}
   def apply_user_email(user, password, attrs) do
     user
     |> User.email_changeset(attrs)
@@ -218,7 +220,7 @@ defmodule Cannery.Accounts do
       %Changeset{data: %User{}}
 
   """
-  @spec change_user_password(User.t(), map()) :: Changeset.t()
+  @spec change_user_password(User.t(), map()) :: Changeset.t(User.t())
   def change_user_password(user, attrs \\ %{}),
     do: User.password_changeset(user, attrs, hash_password: false)
 
@@ -235,7 +237,7 @@ defmodule Cannery.Accounts do
 
   """
   @spec update_user_password(User.t(), String.t(), map()) ::
-          {:ok, User.t()} | {:error, Changeset.t()}
+          {:ok, User.t()} | {:error, Changeset.t(User.t())}
   def update_user_password(user, password, attrs) do
     changeset =
       user
@@ -399,7 +401,7 @@ defmodule Cannery.Accounts do
       {:error, %Changeset{}}
 
   """
-  @spec reset_user_password(User.t(), map()) :: {:ok, User.t()} | {:error, Changeset.t()}
+  @spec reset_user_password(User.t(), map()) :: {:ok, User.t()} | {:error, Changeset.t(User.t())}
   def reset_user_password(user, attrs) do
     Multi.new()
     |> Multi.update(:user, User.password_changeset(user, attrs))
diff --git a/lib/cannery/accounts/user.ex b/lib/cannery/accounts/user.ex
index 95508490..2545c9b6 100644
--- a/lib/cannery/accounts/user.ex
+++ b/lib/cannery/accounts/user.ex
@@ -54,9 +54,9 @@ defmodule Cannery.Accounts.User do
       validations on a LiveView form), this option can be set to `false`.
       Defaults to `true`.
   """
-  @spec registration_changeset(t() | new_user(), attrs :: map()) :: Changeset.t()
+  @spec registration_changeset(t() | new_user(), attrs :: map()) :: Changeset.t(t() | new_user())
   @spec registration_changeset(t() | new_user(), attrs :: map(), opts :: keyword()) ::
-          Changeset.t()
+          Changeset.t(t() | new_user())
   def registration_changeset(user, attrs, opts \\ []) do
     user
     |> cast(attrs, [:email, :password, :role])
@@ -68,12 +68,12 @@ defmodule Cannery.Accounts.User do
   A user changeset for role.
 
   """
-  @spec role_changeset(t(), role :: atom()) :: Changeset.t()
+  @spec role_changeset(t(), role :: atom()) :: Changeset.t(t())
   def role_changeset(user, role) do
     user |> cast(%{"role" => role}, [:role])
   end
 
-  @spec validate_email(Changeset.t()) :: Changeset.t()
+  @spec validate_email(Changeset.t(t() | new_user())) :: Changeset.t(t() | new_user())
   defp validate_email(changeset) do
     changeset
     |> validate_required([:email])
@@ -83,7 +83,8 @@ defmodule Cannery.Accounts.User do
     |> unique_constraint(:email)
   end
 
-  @spec validate_password(Changeset.t(), opts :: keyword()) :: Changeset.t()
+  @spec validate_password(Changeset.t(t() | new_user()), opts :: keyword()) ::
+          Changeset.t(t() | new_user())
   defp validate_password(changeset, opts) do
     changeset
     |> validate_required([:password])
@@ -94,7 +95,8 @@ defmodule Cannery.Accounts.User do
     |> maybe_hash_password(opts)
   end
 
-  @spec maybe_hash_password(Changeset.t(), opts :: keyword()) :: Changeset.t()
+  @spec maybe_hash_password(Changeset.t(t() | new_user()), opts :: keyword()) ::
+          Changeset.t(t() | new_user())
   defp maybe_hash_password(changeset, opts) do
     hash_password? = Keyword.get(opts, :hash_password, true)
     password = get_change(changeset, :password)
@@ -113,7 +115,7 @@ defmodule Cannery.Accounts.User do
 
   It requires the email to change otherwise an error is added.
   """
-  @spec email_changeset(t(), attrs :: map()) :: Changeset.t()
+  @spec email_changeset(t(), attrs :: map()) :: Changeset.t(t())
   def email_changeset(user, attrs) do
     user
     |> cast(attrs, [:email])
@@ -136,8 +138,8 @@ defmodule Cannery.Accounts.User do
       validations on a LiveView form), this option can be set to `false`.
       Defaults to `true`.
   """
-  @spec password_changeset(t(), attrs :: map()) :: Changeset.t()
-  @spec password_changeset(t(), attrs :: map(), opts :: keyword()) :: Changeset.t()
+  @spec password_changeset(t(), attrs :: map()) :: Changeset.t(t())
+  @spec password_changeset(t(), attrs :: map(), opts :: keyword()) :: Changeset.t(t())
   def password_changeset(user, attrs, opts \\ []) do
     user
     |> cast(attrs, [:password])
@@ -148,7 +150,7 @@ defmodule Cannery.Accounts.User do
   @doc """
   Confirms the account by setting `confirmed_at`.
   """
-  @spec confirm_changeset(t() | Changeset.t()) :: Changeset.t()
+  @spec confirm_changeset(t() | Changeset.t(t())) :: Changeset.t(t())
   def confirm_changeset(user_or_changeset) do
     now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
     user_or_changeset |> change(confirmed_at: now)
@@ -174,7 +176,7 @@ defmodule Cannery.Accounts.User do
   @doc """
   Validates the current password otherwise adds an error to the changeset.
   """
-  @spec validate_current_password(Changeset.t(), String.t()) :: Changeset.t()
+  @spec validate_current_password(Changeset.t(t()), String.t()) :: Changeset.t(t())
   def validate_current_password(changeset, password) do
     if valid_password?(changeset.data, password),
       do: changeset,
diff --git a/lib/cannery/ammo.ex b/lib/cannery/ammo.ex
index 40b9391d..e485176e 100644
--- a/lib/cannery/ammo.ex
+++ b/lib/cannery/ammo.ex
@@ -49,7 +49,8 @@ defmodule Cannery.Ammo do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec create_ammo_type(attrs :: map()) :: {:ok, AmmoType.t()} | {:error, Changeset.t()}
+  @spec create_ammo_type(attrs :: map()) ::
+          {:ok, AmmoType.t()} | {:error, Changeset.t(AmmoType.new_ammo_type())}
   def create_ammo_type(attrs \\ %{}),
     do: %AmmoType{} |> AmmoType.changeset(attrs) |> Repo.insert()
 
@@ -66,7 +67,7 @@ defmodule Cannery.Ammo do
 
   """
   @spec update_ammo_type(AmmoType.t(), attrs :: map()) ::
-          {:ok, AmmoType.t()} | {:error, Changeset.t()}
+          {:ok, AmmoType.t()} | {:error, Changeset.t(AmmoType.t())}
   def update_ammo_type(%AmmoType{} = ammo_type, attrs),
     do: ammo_type |> AmmoType.changeset(attrs) |> Repo.update()
 
@@ -82,7 +83,8 @@ defmodule Cannery.Ammo do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec delete_ammo_type(AmmoType.t()) :: {:ok, AmmoType.t()} | {:error, Changeset.t()}
+  @spec delete_ammo_type(AmmoType.t()) ::
+          {:ok, AmmoType.t()} | {:error, Changeset.t(AmmoType.t())}
   def delete_ammo_type(%AmmoType{} = ammo_type), do: ammo_type |> Repo.delete()
 
   @doc """
@@ -106,8 +108,10 @@ defmodule Cannery.Ammo do
       %Ecto.Changeset{data: %AmmoType{}}
 
   """
-  @spec change_ammo_type(AmmoType.t() | AmmoType.new_ammo_type()) :: Changeset.t()
-  @spec change_ammo_type(AmmoType.t() | AmmoType.new_ammo_type(), attrs :: map()) :: Changeset.t()
+  @spec change_ammo_type(AmmoType.t() | AmmoType.new_ammo_type()) ::
+          Changeset.t(AmmoType.t() | AmmoType.new_ammo_type())
+  @spec change_ammo_type(AmmoType.t() | AmmoType.new_ammo_type(), attrs :: map()) ::
+          Changeset.t(AmmoType.t() | AmmoType.new_ammo_type())
   def change_ammo_type(%AmmoType{} = ammo_type, attrs \\ %{}),
     do: AmmoType.changeset(ammo_type, attrs)
 
@@ -159,7 +163,8 @@ defmodule Cannery.Ammo do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec create_ammo_group(attrs :: map()) :: {:ok, AmmoGroup.t()} | {:error, Changeset.t()}
+  @spec create_ammo_group(attrs :: map()) ::
+          {:ok, AmmoGroup.t()} | {:error, Changeset.t(AmmoGroup.new_ammo_group())}
   def create_ammo_group(attrs \\ %{}),
     do: %AmmoGroup{} |> AmmoGroup.changeset(attrs) |> Repo.insert()
 
@@ -176,7 +181,7 @@ defmodule Cannery.Ammo do
 
   """
   @spec update_ammo_group(AmmoGroup.t(), attrs :: map()) ::
-          {:ok, AmmoGroup.t()} | {:error, Changeset.t()}
+          {:ok, AmmoGroup.t()} | {:error, Changeset.t(AmmoGroup.t())}
   def update_ammo_group(%AmmoGroup{} = ammo_group, attrs),
     do: ammo_group |> AmmoGroup.changeset(attrs) |> Repo.update()
 
@@ -192,7 +197,8 @@ defmodule Cannery.Ammo do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec delete_ammo_group(AmmoGroup.t()) :: {:ok, AmmoGroup.t()} | {:error, Changeset.t()}
+  @spec delete_ammo_group(AmmoGroup.t()) ::
+          {:ok, AmmoGroup.t()} | {:error, Changeset.t(AmmoGroup.t())}
   def delete_ammo_group(%AmmoGroup{} = ammo_group), do: ammo_group |> Repo.delete()
 
   @doc """
diff --git a/lib/cannery/ammo/ammo_group.ex b/lib/cannery/ammo/ammo_group.ex
index 261ddd26..463b70cf 100644
--- a/lib/cannery/ammo/ammo_group.ex
+++ b/lib/cannery/ammo/ammo_group.ex
@@ -47,7 +47,7 @@ defmodule Cannery.Ammo.AmmoGroup do
   @type id :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_ammo_group(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_ammo_group(), attrs :: map()) :: Changeset.t(t() | new_ammo_group())
   def changeset(ammo_group, attrs) do
     ammo_group
     |> cast(attrs, [:count, :price_paid, :notes, :tag_id, :ammo_type_id, :container_id, :user_id])
diff --git a/lib/cannery/ammo/ammo_type.ex b/lib/cannery/ammo/ammo_type.ex
index e29d21f1..4cc007ad 100644
--- a/lib/cannery/ammo/ammo_type.ex
+++ b/lib/cannery/ammo/ammo_type.ex
@@ -38,7 +38,7 @@ defmodule Cannery.Ammo.AmmoType do
   @type id :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_ammo_type(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_ammo_type(), attrs :: map()) :: Changeset.t(t() | new_ammo_type())
   def changeset(ammo_type, attrs) do
     ammo_type
     |> cast(attrs, [:name, :desc, :case_material, :bullet_type, :grain, :manufacturer])
diff --git a/lib/cannery/containers.ex b/lib/cannery/containers.ex
index 096737cc..39100acb 100644
--- a/lib/cannery/containers.ex
+++ b/lib/cannery/containers.ex
@@ -50,7 +50,8 @@ defmodule Cannery.Containers do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec create_container(attrs :: map()) :: {:ok, Container.t()} | {:error, Changeset.t()}
+  @spec create_container(attrs :: map()) ::
+          {:ok, Container.t()} | {:error, Changeset.t(Container.new_container())}
   def create_container(attrs) do
     %Container{} |> Container.changeset(attrs) |> Repo.insert()
   end
@@ -67,8 +68,8 @@ defmodule Cannery.Containers do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec update_container(Container.t() | Ecto.Changeset.t(), attrs :: map()) ::
-          {:ok, Container.t()} | {:error, Ecto.Changeset.t()}
+  @spec update_container(Container.t(), attrs :: map()) ::
+          {:ok, Container.t()} | {:error, Changeset.t(Container.t())}
   def update_container(container, attrs) do
     container |> Container.changeset(attrs) |> Repo.update()
   end
@@ -85,8 +86,8 @@ defmodule Cannery.Containers do
       {:error, %Ecto.Changeset{}}
 
   """
-  @spec delete_container(Container.t() | Ecto.Changeset.t()) ::
-          {:ok, Container.t()} | {:error, Ecto.Changeset.t()}
+  @spec delete_container(Container.t()) ::
+          {:ok, Container.t()} | {:error, Changeset.t(Container.t())}
   def delete_container(container), do: container |> Repo.delete()
 
   @doc """
@@ -98,7 +99,7 @@ defmodule Cannery.Containers do
       %Container{}
 
   """
-  @spec delete_container!(Container.t() | Ecto.Changeset.t()) :: Container.t()
+  @spec delete_container!(Container.t()) :: Container.t()
   def delete_container!(container), do: container |> Repo.delete!()
 
   @doc """
@@ -113,9 +114,10 @@ defmodule Cannery.Containers do
       %Ecto.Changeset{data: %Container{}}
 
   """
-  @spec change_container(Container.t() | Container.new_container()) :: Changeset.t()
+  @spec change_container(Container.t() | Container.new_container()) ::
+          Changeset.t(Container.t() | Container.new_container())
   @spec change_container(Container.t() | Container.new_container(), attrs :: map()) ::
-          Changeset.t()
+          Changeset.t(Container.t() | Container.new_container())
   def change_container(container, attrs \\ %{}), do: container |> Container.changeset(attrs)
 
   @doc """
diff --git a/lib/cannery/containers/container.ex b/lib/cannery/containers/container.ex
index d7718436..15339dc1 100644
--- a/lib/cannery/containers/container.ex
+++ b/lib/cannery/containers/container.ex
@@ -36,7 +36,7 @@ defmodule Cannery.Containers.Container do
   @type id :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_container(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_container(), attrs :: map()) :: Changeset.t(t() | new_container())
   def changeset(container, attrs) do
     container
     |> cast(attrs, [:name, :desc, :type, :location, :user_id])
diff --git a/lib/cannery/containers/container_tag.ex b/lib/cannery/containers/container_tag.ex
index ac4ad835..ee0f8ee5 100644
--- a/lib/cannery/containers/container_tag.ex
+++ b/lib/cannery/containers/container_tag.ex
@@ -31,7 +31,8 @@ defmodule Cannery.Containers.ContainerTag do
   @type id :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_container_tag(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_container_tag(), attrs :: map()) ::
+          Changeset.t(t() | new_container_tag())
   def changeset(container_tag, attrs) do
     container_tag
     |> cast(attrs, [:tag_id, :container_id])
diff --git a/lib/cannery/invites.ex b/lib/cannery/invites.ex
index bf8ab43e..45033c75 100644
--- a/lib/cannery/invites.ex
+++ b/lib/cannery/invites.ex
@@ -93,11 +93,11 @@ defmodule Cannery.Invites do
       {:ok, %Invite{}}
 
       iex> create_invite(%User{id: "1"}, %{field: bad_value})
-      {:error, %Ecto.Changeset{}}
+      {:error, %Changeset{}}
 
   """
   @spec create_invite(User.t() | User.id(), attrs :: map()) ::
-          {:ok, Invite.t()} | {:error, Changeset.t()}
+          {:ok, Invite.t()} | {:error, Changeset.t(Invite.new_invite())}
   def create_invite(%{id: user_id}, attrs), do: create_invite(user_id, attrs)
 
   def create_invite(user_id, attrs) when not (user_id |> is_nil()) do
@@ -120,11 +120,11 @@ defmodule Cannery.Invites do
       {:ok, %Invite{}}
 
       iex> update_invite(invite, %{field: bad_value})
-      {:error, %Ecto.Changeset{}}
+      {:error, %Changeset{}}
 
   """
   @spec update_invite(Invite.t(), attrs :: map()) ::
-          {:ok, Invite.t()} | {:error, Ecto.Changeset.t()}
+          {:ok, Invite.t()} | {:error, Changeset.t(Invite.t())}
   def update_invite(invite, attrs), do: invite |> Invite.changeset(attrs) |> Repo.update()
 
   @doc """
@@ -136,10 +136,10 @@ defmodule Cannery.Invites do
       {:ok, %Invite{}}
 
       iex> delete_invite(invite)
-      {:error, %Ecto.Changeset{}}
+      {:error, %Changeset{}}
 
   """
-  @spec delete_invite(Invite.t()) :: {:ok, Invite.t()} | {:error, Ecto.Changeset.t()}
+  @spec delete_invite(Invite.t()) :: {:ok, Invite.t()} | {:error, Changeset.t(Invite.t())}
   def delete_invite(invite), do: invite |> Repo.delete()
 
   @doc """
@@ -155,15 +155,17 @@ defmodule Cannery.Invites do
   def delete_invite!(invite), do: invite |> Repo.delete!()
 
   @doc """
-  Returns an `%Ecto.Changeset{}` for tracking invite changes.
+  Returns an `%Changeset{}` for tracking invite changes.
 
   ## Examples
 
       iex> change_invite(invite)
-      %Ecto.Changeset{data: %Invite{}}
+      %Changeset{data: %Invite{}}
 
   """
-  @spec change_invite(Invite.t() | Invite.new_invite()) :: Ecto.Changeset.t()
-  @spec change_invite(Invite.t() | Invite.new_invite(), attrs :: map()) :: Ecto.Changeset.t()
+  @spec change_invite(Invite.t() | Invite.new_invite()) ::
+          Changeset.t(Invite.t() | Invite.new_invite())
+  @spec change_invite(Invite.t() | Invite.new_invite(), attrs :: map()) ::
+          Changeset.t(Invite.t() | Invite.new_invite())
   def change_invite(invite, attrs \\ %{}), do: invite |> Invite.changeset(attrs)
 end
diff --git a/lib/cannery/invites/invite.ex b/lib/cannery/invites/invite.ex
index 36031c17..e3e06e91 100644
--- a/lib/cannery/invites/invite.ex
+++ b/lib/cannery/invites/invite.ex
@@ -38,7 +38,7 @@ defmodule Cannery.Invites.Invite do
   @type id :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_invite(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_invite(), attrs :: map()) :: Changeset.t(t() | new_invite())
   def changeset(invite, attrs) do
     invite
     |> cast(attrs, [:name, :token, :uses_left, :disabled_at, :user_id])
diff --git a/lib/cannery/tags.ex b/lib/cannery/tags.ex
index 5ff7ad18..8ee6cee1 100644
--- a/lib/cannery/tags.ex
+++ b/lib/cannery/tags.ex
@@ -49,7 +49,7 @@ defmodule Cannery.Tags do
       {:error, %Changeset{}}
 
   """
-  @spec create_tag(attrs :: map()) :: {:ok, Tag.t()} | {:error, Changeset.t()}
+  @spec create_tag(attrs :: map()) :: {:ok, Tag.t()} | {:error, Changeset.t(Tag.new_tag())}
   def create_tag(attrs), do: %Tag{} |> Tag.changeset(attrs) |> Repo.insert()
 
   @doc """
@@ -64,7 +64,7 @@ defmodule Cannery.Tags do
       {:error, %Changeset{}}
 
   """
-  @spec update_tag(Tag.t(), attrs :: map()) :: {:ok, Tag.t()} | {:error, Changeset.t()}
+  @spec update_tag(Tag.t(), attrs :: map()) :: {:ok, Tag.t()} | {:error, Changeset.t(Tag.t())}
   def update_tag(tag, attrs), do: tag |> Tag.changeset(attrs) |> Repo.update()
 
   @doc """
@@ -79,7 +79,7 @@ defmodule Cannery.Tags do
       {:error, %Changeset{}}
 
   """
-  @spec delete_tag(Tag.t()) :: {:ok, Tag.t()} | {:error, Changeset.t()}
+  @spec delete_tag(Tag.t()) :: {:ok, Tag.t()} | {:error, Changeset.t(Tag.t())}
   def delete_tag(tag), do: tag |> Repo.delete()
 
   @doc """
@@ -103,8 +103,9 @@ defmodule Cannery.Tags do
       %Changeset{data: %Tag{}}
 
   """
-  @spec change_tag(Tag.t() | Tag.new_tag()) :: Changeset.t()
-  @spec change_tag(Tag.t() | Tag.new_tag(), attrs :: map()) :: Changeset.t()
+  @spec change_tag(Tag.t() | Tag.new_tag()) :: Changeset.t(Tag.t() | Tag.new_tag())
+  @spec change_tag(Tag.t() | Tag.new_tag(), attrs :: map()) ::
+          Changeset.t(Tag.t() | Tag.new_tag())
   def change_tag(tag, attrs \\ %{}), do: Tag.changeset(tag, attrs)
 
   @doc """
diff --git a/lib/cannery/tags/tag.ex b/lib/cannery/tags/tag.ex
index 5abc8e5b..2f74436f 100644
--- a/lib/cannery/tags/tag.ex
+++ b/lib/cannery/tags/tag.ex
@@ -35,7 +35,7 @@ defmodule Cannery.Tags.Tag do
   @type id() :: UUID.t()
 
   @doc false
-  @spec changeset(t() | new_tag(), attrs :: map()) :: Changeset.t()
+  @spec changeset(t() | new_tag(), attrs :: map()) :: Changeset.t(t() | new_tag())
   def changeset(tag, attrs) do
     tag
     |> cast(attrs, [:name, :bg_color, :text_color, :user_id])