Added a search feature for List()

examples/list_search.py

@@ -0,0 +1,25 @@
+import os
+import sys
+from pprint import pprint
+
+
+sys.path.append(os.path.realpath("."))
+import inquirer  # noqa
+
+
+# To make the search case-insensitive
+def matcher(entry, search):
+    return entry.lower().startswith(search.lower())
+
+
+questions = [
+    inquirer.List(
+        "size", message="What size do you need?",
+        choices=["Jumbo", "Large", "Standard"],
+        carousel=True, search=True, matcher=matcher
+    ),
+]
+
+answers = inquirer.prompt(questions)
+
+pprint(answers)

src/inquirer/questions.py

@@ -159,10 +159,14 @@ def __init__(
         carousel=False,
         other=False,
         autocomplete=None,
+        search=False,
+        matcher=None
     ):
         super().__init__(name, message, choices, default, ignore, validate, hints=hints, other=other)
         self.carousel = carousel
         self.autocomplete = autocomplete
+        self.search = search
+        self.matcher = matcher
 
 
 class Checkbox(Question):

src/inquirer/render/console/_list.py

@@ -11,12 +11,16 @@ class List(BaseConsoleRender):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.current = self._current_index()
+        self.input = ""
 
     @property
     def is_long(self):
         choices = self.question.choices or []
         return len(choices) >= MAX_OPTIONS_DISPLAYED_AT_ONCE
 
+    def get_current_value(self):
+        return self.input if self.question.search else ""
+
     def get_hint(self):
         try:
             choice = self.question.choices[self.current]
@@ -90,6 +94,18 @@ def process_input(self, pressed):
 
             raise errors.EndOfInput(getattr(value, "value", value))
 
+        if self.question.matcher is not None:
+            if pressed.isprintable():
+                self.input += pressed
+                for choice in self.question.choices:
+                    if self.question.matcher(choice, self.input):
+                        self.current = self.question.choices.index(choice)
+                        break
+
+            # BACKSPACE gives a \x7f on linux while it gives a \x08 on windows
+            if pressed == chr(127) or pressed == chr(8):
+                self.input = self.input[:-1]
+
         if pressed == key.CTRL_C:
             raise KeyboardInterrupt()
 

tests/integration/console_render/test_list.py

@@ -132,6 +132,36 @@ def test_ctrl_c_breaks_execution(self):
         with pytest.raises(KeyboardInterrupt):
             sut.render(question)
 
+    def test_type_char(self):
+        stdin = helper.event_factory('b', 'A', 'z', key.ENTER)
+        message = "Foo message"
+        variable = "Bar variable"
+        choices = ["foo", "bar", "bazz"]
+
+        # To make the search case-insensitive
+        def matcher(entry, search):
+            return entry.lower().startswith(search.lower())
+
+        question = questions.List(variable, message, choices=choices, carousel=True, matcher=matcher)
+
+        sut = ConsoleRender(event_generator=stdin)
+        result = sut.render(question)
+
+        assert result == "bazz"
+
+    def test_type_char_without_matcher(self):
+        stdin = helper.event_factory('b', 'A', 'z', key.ENTER)
+        message = "Foo message"
+        variable = "Bar variable"
+        choices = ["foo", "bar", "bazz"]
+
+        question = questions.List(variable, message, choices=choices, carousel=True)
+
+        sut = ConsoleRender(event_generator=stdin)
+        result = sut.render(question)
+
+        assert result == "foo"
+
     def test_first_hint_is_shown(self):
         stdin = helper.event_factory(key.ENTER)
         message = "Foo message"