update

phoenix/deps/ecto_sql/lib/mix/ecto_sql.ex

@@ -0,0 +1,45 @@
+defmodule Mix.EctoSQL do
+  @moduledoc false
+
+  @doc """
+  Ensures the given repository's migrations paths exists on the file system.
+  """
+  @spec ensure_migrations_paths(Ecto.Repo.t(), Keyword.t()) :: [String.t()]
+  def ensure_migrations_paths(repo, opts) do
+    paths = Keyword.get_values(opts, :migrations_path)
+    paths = if paths == [], do: [Path.join(source_repo_priv(repo), "migrations")], else: paths
+
+    if not Mix.Project.umbrella?() do
+      for path <- paths, not File.dir?(path) do
+        raise_missing_migrations(Path.relative_to_cwd(path), repo)
+      end
+    end
+
+    paths
+  end
+
+  defp raise_missing_migrations(path, repo) do
+    Mix.raise("""
+    Could not find migrations directory #{inspect(path)}
+    for repo #{inspect(repo)}.
+
+    This may be because you are in a new project and the
+    migration directory has not been created yet. Creating an
+    empty directory at the path above will fix this error.
+
+    If you expected existing migrations to be found, please
+    make sure your repository has been properly configured
+    and the configured path exists.
+    """)
+  end
+
+  @doc """
+  Returns the private repository path relative to the source.
+  """
+  def source_repo_priv(repo) do
+    config = repo.config()
+    priv = config[:priv] || "priv/#{repo |> Module.split() |> List.last() |> Macro.underscore()}"
+    app = Keyword.fetch!(config, :otp_app)
+    Path.join(Mix.Project.deps_paths()[app] || File.cwd!(), priv)
+  end
+end