From e1379d8ead15edd6cc4369c22274345982edc95a Mon Sep 17 00:00:00 2001
From: Jess Archer <jess@jessarcher.com>
Date: Fri, 27 Oct 2023 23:53:59 +1000
Subject: [PATCH] Allow empty strings on `select` prompt (#99)

* Allow empty string keys on `select` prompts

* Remove truthy check on `required`
---
 src/Prompt.php                     | 12 ++++++++++--
 src/SelectPrompt.php               |  8 ++++++++
 tests/Feature/SelectPromptTest.php | 14 ++++++++++++++
 3 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/src/Prompt.php b/src/Prompt.php
index dfa0657e..fcc80baf 100644
--- a/src/Prompt.php
+++ b/src/Prompt.php
@@ -307,9 +307,9 @@ private function validate(mixed $value): void
     {
         $this->validated = true;
 
-        if (($this->required ?? false) && ($value === '' || $value === [] || $value === false || $value === null)) {
+        if ($this->required !== false && $this->isInvalidWhenRequired($value)) {
             $this->state = 'error';
-            $this->error = is_string($this->required) ? $this->required : 'Required.';
+            $this->error = is_string($this->required) && strlen($this->required) > 0 ? $this->required : 'Required.';
 
             return;
         }
@@ -330,6 +330,14 @@ private function validate(mixed $value): void
         }
     }
 
+    /**
+     * Determine whether the given value is invalid when the prompt is required.
+     */
+    protected function isInvalidWhenRequired(mixed $value): bool
+    {
+        return $value === '' || $value === [] || $value === false || $value === null;
+    }
+
     /**
      * Check whether the environment can support the prompt.
      */
diff --git a/src/SelectPrompt.php b/src/SelectPrompt.php
index 018b956c..6c9e5ed8 100644
--- a/src/SelectPrompt.php
+++ b/src/SelectPrompt.php
@@ -96,4 +96,12 @@ public function visible(): array
     {
         return array_slice($this->options, $this->firstVisible, $this->scroll, preserve_keys: true);
     }
+
+    /**
+     * Determine whether the given value is invalid when the prompt is required.
+     */
+    protected function isInvalidWhenRequired(mixed $value): bool
+    {
+        return $value === null;
+    }
 }
diff --git a/tests/Feature/SelectPromptTest.php b/tests/Feature/SelectPromptTest.php
index 26138776..6d57d3fb 100644
--- a/tests/Feature/SelectPromptTest.php
+++ b/tests/Feature/SelectPromptTest.php
@@ -257,6 +257,20 @@
     expect($result)->toBe('Blue');
 });
 
+it('allows empty strings', function () {
+    Prompt::fake([Key::ENTER]);
+
+    $result = select(
+        label: 'What is your favorite color?',
+        options: [
+            '' => 'Empty',
+            'not-empty' => 'Not empty',
+        ],
+    );
+
+    expect($result)->toBe('');
+});
+
 it('fails when there is no default in non-interactive mode', function () {
     Prompt::interactive(false);