feat: add prompt to emitter

Signed-off-by: Dariusz Duda <dariusz.duda@canonical.com>

.pre-commit-config.yaml

@@ -12,17 +12,15 @@ repos:
       - id: check-toml
       - id: fix-byte-order-marker
       - id: mixed-line-ending
-  - repo: https://github.com/charliermarsh/ruff-pre-commit
+  - repo: https://github.com/astral-sh/ruff-pre-commit
     # renovate: datasource=pypi;depName=ruff
-    rev: "v0.0.269"
+    rev: "v0.8.3"
     hooks:
+      # Run the linter
       - id: ruff
         args: [--fix, --exit-non-zero-on-fix]
-  - repo: https://github.com/psf/black
-    # renovate: datasource=pypi;depName=black
-    rev: "23.3.0"
-    hooks:
-      - id: black
+      # Run the formatter
+      - id: ruff-format
   - repo: https://github.com/adrienverge/yamllint.git
     # renovate: datasource=pypi;depName=yamllint
     rev: "v1.32.0"

craft_cli/messages.py

@@ -25,6 +25,7 @@
 
 import enum
 import functools
+import getpass
 import logging
 import os
 import pathlib
@@ -806,6 +807,27 @@ def confirm(self, prompt: str, *, default: bool = False) -> bool:
             return False
         return default
 
+    @_active_guard()
+    def prompt(self, prompt: str, *, hide: bool = False) -> str:
+        """Prompt user for input.
+
+        If stdin is not a tty a CraftError is raised.
+
+        :param hide: hide user input if True.
+        :returns: value that was provided by user.
+        :raises: CraftError if shell is not interactive or input is empty
+        """
+        if not sys.stdin.isatty():
+            raise errors.CraftError("prompting not possible without tty")
+
+        method: Callable[[str], str] = getpass.getpass if hide else input  # type: ignore[assignment]
+
+        with self.pause():
+            val = method(prompt).strip()
+        if not val:
+            raise errors.CraftError("input cannot be empty")
+        return val
+
 
 # module-level instantiated Emitter; this is the instance all code shall use and Emitter
 # shall not be instantiated again for the process' run

docs/changelog.rst

@@ -7,6 +7,11 @@ Changelog
 See the `Releases page`_ on GitHub for a complete list of commits that are
 included in each version.
 
+2.14.0 (2025-MMM-DD)
+--------------------
+
+- Add a ``prompt`` method to the emmiter to ask for user input.
+
 2.13.0 (2024-Dec-16)
 --------------------
 

tests/unit/test_messages_emitter.py

@@ -20,9 +20,11 @@
 import sys
 from unittest import mock
 from unittest.mock import call, patch
+from typing import cast, Callable
 
 import craft_cli
 import pytest
+import pytest_mock
 
 from craft_cli import messages
 from craft_cli.errors import CraftError, CraftCommandError
@@ -879,7 +881,7 @@ def test_reporterror_simple_message_developer_modes(mode, get_initiated_emitter)
 
 def test_reporterror_detailed_info_quiet_modes(get_initiated_emitter):
     """Report an error having detailed information, in final user modes.
-    
+
     Check that "quiet" is indeed quiet.
     """
     emitter = get_initiated_emitter(EmitterMode.QUIET)
@@ -1251,16 +1253,72 @@ def test_confirm_with_user(get_initiated_emitter, user_input, expected, mock_inp
     assert mock_input.mock_calls == [call("prompt [y/N]: ")]
 
 
-def test_confirm_with_user_pause_emitter(get_initiated_emitter, emitter_mode, mock_isatty, mocker):
+@pytest.fixture
+def initiated_emitter(get_initiated_emitter, mock_isatty, emitter_mode) -> Emitter:
+    return cast(Emitter, get_initiated_emitter(emitter_mode))
+
+
+@pytest.fixture
+def fake_input(initiated_emitter: Emitter) -> Callable[[str], Callable[[str], str]]:
+    def get_fake_input_wrapper(input_val: str) -> Callable[[str], str]:
+        def _inner(prompt: str) -> str:
+            assert initiated_emitter._stopped
+            return input_val
+
+        return _inner
+
+    return get_fake_input_wrapper
+
+
+def test_confirm_with_user_pause_emitter(
+    initiated_emitter: Emitter,
+    fake_input: Callable[[str], Callable[[str], str]],
+    mocker,
+):
     """The emitter should be paused when using the terminal."""
-    mock_isatty.return_value = True
+    mocker.patch("builtins.input", fake_input(""))
+
+    initiated_emitter.confirm("prompt")
+
+
+def test_prompt_returns_user_input(
+    initiated_emitter: Emitter,
+    fake_input: Callable[[str], Callable[[str], str]],
+    mocker: pytest_mock.MockerFixture,
+):
+    """The emitter should return user input."""
+    mocker.patch("builtins.input", fake_input("some-input"))
+
+    assert initiated_emitter.prompt("prompt") == "some-input"
+
+
+def test_prompt_returns_secret_input(
+    initiated_emitter: Emitter,
+    fake_input: Callable[[str], Callable[[str], str]],
+    mocker: pytest_mock.MockerFixture,
+):
+    """The emitter should return user secret input."""
+    mocker.patch("getpass.getpass", fake_input("some-secret-input"))
+
+    assert initiated_emitter.prompt("prompt", hide=True) == "some-secret-input"
+
+def test_prompt_errors_out_without_tty(
+    get_initiated_emitter, mock_isatty: mock.MagicMock, emitter_mode,
+):
+    """The emitter should error out if no tty available."""
+    mock_isatty.return_value = False
     emit = get_initiated_emitter(emitter_mode)
 
-    def fake_input(_prompt):
-        """Check if the Emitter is paused."""
-        assert emit._stopped
-        return ""
+    with pytest.raises(CraftError, match="prompting not possible without tty"):
+        emit.prompt("no prompting without tty!")
 
-    mocker.patch("builtins.input", fake_input)
+def test_prompt_does_not_allow_empty_input(
+    initiated_emitter: Emitter,
+    fake_input: Callable[[str], Callable[[str], str]],
+    mocker: pytest_mock.MockerFixture,
+):
+    """The emitter should not allow empty input."""
+    mocker.patch("builtins.input", fake_input(""))
 
-    emit.confirm("prompt")
+    with pytest.raises(CraftError, match="input cannot be empty") as error:
+        initiated_emitter.prompt("prompt")