Add a fake shell command to avoid using cmd all the time

lib/toolshed.ex

@@ -22,6 +22,7 @@ defmodule Toolshed do
     * `date/0`         - print out the current date and time
     * `dmesg/0`        - print kernel messages (Nerves-only)
     * `exit/0`         - exit out of an IEx session
+    * `fake_shell/0`   - starts a sh like session that sends all lines to `cmd/1`
     * `fw_validate/0`  - marks the current image as valid (check Nerves system if supported)
     * `geo/1`          - print out a rough physical location
     * `grep/2`         - print out lines that match a regular expression

lib_src/core/fake_shell.ex

@@ -0,0 +1,56 @@
+# SPDX-FileCopyrightText: 2025 Marc Lainez
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+defmodule Toolshed.Core.FakeShell do
+  @prompt "fksh> "
+
+  @doc """
+  Start an interactive fake shell session.
+
+  The shell reads lines from `IO.gets/1` and delegates command execution to
+  `Toolshed.cmd/1`. It is intended for manual use or lightweight integration
+  testing where an interactive prompt is convenient.
+
+   Example
+
+      iex> Toolshed.fake_shell()
+      Starting fake shell. Type 'exit' to quit.
+      fksh> echo hello
+      ...
+
+  The function returns `:ok` when the user types `exit`.
+  """
+  @spec fake_shell() :: :ok
+  def fake_shell() do
+    IO.puts("Starting fake shell. Type 'exit' to quit.")
+    fake_shell_loop()
+  end
+
+  defp fake_shell_loop() do
+    case IO.gets(@prompt) do
+      :eof ->
+        :ok
+
+      "exit\n" ->
+        :ok
+
+      line ->
+        line
+        |> String.trim()
+        |> exec()
+
+        fake_shell_loop()
+    end
+  end
+
+  defp exec(""), do: :ok
+
+  defp exec(cmdline) do
+    _ = Toolshed.cmd(cmdline)
+    :ok
+  rescue
+    e ->
+      IO.puts("error: #{inspect(e)}")
+  end
+end

test/toolshed_test.exs

@@ -12,6 +12,7 @@ defmodule ToolshedTest do
     cat: 1,
     cmd: 1,
     date: 0,
+    fake_shell: 0,
     geo: 0,
     geo: 1,
     grep: 2,