feature #35400 [RFC][DX][OptionsResolver] Allow setting info message per option (yceruto)

This PR was merged into the 5.1-dev branch.

Discussion
----------

[RFC][DX][OptionsResolver] Allow setting info message per option

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | -
| License       | MIT
| Doc PR        | TODO

This is a DX proposal that will help in debugging/errors to better understand the meaning of one defined option.

This is how you'd use it:
```php
$resolver = new OptionsResolver();
$resolver->setDefined('date');
$resolver->setAllowedTypes('date', \DateTime::class);
$resolver->setInfo('date', 'A future date'); // <-- NEW
// ...
```
This information may be useful for those options where their name cannot be intuitive enough, or their purpose is too complex. Here is an example (based on the example above):
```php
// ...
$resolver->setAllowedValues('date', static function ($value): bool {
    return $value >= new \DateTime('now');
});
```
So, if you introduce a date value that does not match the criteria, you will get this error message:

**Before:**
```
The option "date" with value DateTime is invalid.
```
Note that the allowed value is not printable in this case, hence the error message cannot be clear at all.

**After:**
```
The option "date" with value DateTime is invalid. Info: A future date.
```
Although a more accurate error message can be triggered within the `\Closure` if desired.

Also you'll see this info message on `debug:form` command (see tests), then you have in advance the informative description of any option.

What do you think?

Commits
-------

0477a06d8a Allow setting one info message per option

Author: fabpot

CHANGELOG.md

@@ -5,6 +5,7 @@ CHANGELOG
 -----
 
  * added fluent configuration of options using `OptionResolver::define()`
+ * added `setInfo()` and `getInfo()` methods
 
 5.0.0
 -----

OptionConfigurator.php

@@ -124,4 +124,18 @@ public function required(): self
 
         return $this;
     }
+
+    /**
+     * Sets an info message for an option.
+     *
+     * @return $this
+     *
+     * @throws AccessException If called from a lazy option or normalizer
+     */
+    public function info(string $info): self
+    {
+        $this->resolver->setInfo($this->name, $info);
+
+        return $this;
+    }
 }

OptionsResolver.php

@@ -71,6 +71,11 @@ class OptionsResolver implements Options
      */
     private $allowedTypes = [];
 
+    /**
+     * A list of info messages for each option.
+     */
+    private $info = [];
+
     /**
      * A list of closures for evaluating lazy options.
      */
@@ -715,6 +720,41 @@ public function define(string $option): OptionConfigurator
         return new OptionConfigurator($option, $this);
     }
 
+    /**
+     * Sets an info message for an option.
+     *
+     * @return $this
+     *
+     * @throws UndefinedOptionsException If the option is undefined
+     * @throws AccessException           If called from a lazy option or normalizer
+     */
+    public function setInfo(string $option, string $info): self
+    {
+        if ($this->locked) {
+            throw new AccessException('The Info message cannot be set from a lazy option or normalizer.');
+        }
+
+        if (!isset($this->defined[$option])) {
+            throw new UndefinedOptionsException(sprintf('The option "%s" does not exist. Defined options are: "%s".', $this->formatOptions([$option]), implode('", "', array_keys($this->defined))));
+        }
+
+        $this->info[$option] = $info;
+
+        return $this;
+    }
+
+    /**
+     * Gets the info message for an option.
+     */
+    public function getInfo(string $option): ?string
+    {
+        if (!isset($this->defined[$option])) {
+            throw new UndefinedOptionsException(sprintf('The option "%s" does not exist. Defined options are: "%s".', $this->formatOptions([$option]), implode('", "', array_keys($this->defined))));
+        }
+
+        return $this->info[$option] ?? null;
+    }
+
     /**
      * Removes the option with the given name.
      *
@@ -734,7 +774,7 @@ public function remove($optionNames)
 
         foreach ((array) $optionNames as $option) {
             unset($this->defined[$option], $this->defaults[$option], $this->required[$option], $this->resolved[$option]);
-            unset($this->lazy[$option], $this->normalizers[$option], $this->allowedTypes[$option], $this->allowedValues[$option]);
+            unset($this->lazy[$option], $this->normalizers[$option], $this->allowedTypes[$option], $this->allowedValues[$option], $this->info[$option]);
         }
 
         return $this;
@@ -763,6 +803,7 @@ public function clear()
         $this->allowedTypes = [];
         $this->allowedValues = [];
         $this->deprecated = [];
+        $this->info = [];
 
         return $this;
     }
@@ -996,6 +1037,10 @@ public function offsetGet($option, bool $triggerDeprecation = true)
                     );
                 }
 
+                if (isset($this->info[$option])) {
+                    $message .= sprintf(' Info: %s.', $this->info[$option]);
+                }
+
                 throw new InvalidOptionsException($message);
             }
         }

Tests/OptionsResolverTest.php

@@ -14,7 +14,9 @@
 use PHPUnit\Framework\Assert;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\OptionsResolver\Debug\OptionsResolverIntrospector;
+use Symfony\Component\OptionsResolver\Exception\AccessException;
 use Symfony\Component\OptionsResolver\Exception\InvalidOptionsException;
+use Symfony\Component\OptionsResolver\Exception\UndefinedOptionsException;
 use Symfony\Component\OptionsResolver\Options;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 
@@ -2399,6 +2401,7 @@ public function testResolveOptionsDefinedByOptionConfigurator()
             ->normalize(static function (Options $options, $value) {
                 return $value;
             })
+            ->info('info message')
         ;
         $introspector = new OptionsResolverIntrospector($this->resolver);
 
@@ -2409,5 +2412,63 @@ public function testResolveOptionsDefinedByOptionConfigurator()
         $this->assertSame(['string', 'bool'], $introspector->getAllowedTypes('foo'));
         $this->assertSame(['bar', 'zab'], $introspector->getAllowedValues('foo'));
         $this->assertCount(1, $introspector->getNormalizers('foo'));
+        $this->assertSame('info message', $this->resolver->getInfo('foo'));
+    }
+
+    public function testGetInfo()
+    {
+        $info = 'The option info message';
+        $this->resolver->setDefined('foo');
+        $this->resolver->setInfo('foo', $info);
+
+        $this->assertSame($info, $this->resolver->getInfo('foo'));
+    }
+
+    public function testSetInfoOnNormalization()
+    {
+        $this->expectException(AccessException::class);
+        $this->expectExceptionMessage('The Info message cannot be set from a lazy option or normalizer.');
+
+        $this->resolver->setDefined('foo');
+        $this->resolver->setNormalizer('foo', static function (Options $options, $value) {
+            $options->setInfo('foo', 'Info');
+        });
+
+        $this->resolver->resolve(['foo' => 'bar']);
+    }
+
+    public function testSetInfoOnUndefinedOption()
+    {
+        $this->expectException(UndefinedOptionsException::class);
+        $this->expectExceptionMessage('The option "bar" does not exist. Defined options are: "foo".');
+
+        $this->resolver->setDefined('foo');
+        $this->resolver->setInfo('bar', 'The option info message');
+    }
+
+    public function testGetInfoOnUndefinedOption2()
+    {
+        $this->expectException(UndefinedOptionsException::class);
+        $this->expectExceptionMessage('The option "bar" does not exist. Defined options are: "foo".');
+
+        $this->resolver->setDefined('foo');
+        $this->resolver->getInfo('bar');
+    }
+
+    public function testInfoOnInvalidValue()
+    {
+        $this->expectException(InvalidOptionsException::class);
+        $this->expectExceptionMessage('The option "expires" with value DateTime is invalid. Info: A future date time.');
+
+        $this->resolver
+            ->setRequired('expires')
+            ->setInfo('expires', 'A future date time')
+            ->setAllowedTypes('expires', \DateTime::class)
+            ->setAllowedValues('expires', static function ($value) {
+                return $value >= new \DateTime('now');
+            })
+        ;
+
+        $this->resolver->resolve(['expires' => new \DateTime('-1 hour')]);
     }
 }