Add casting for string type

Author: Kirill Nesmeyanov

src/Type/StringType.php

@@ -9,6 +9,12 @@
 
 class StringType implements TypeInterface
 {
+    protected const NULL_TO_STRING  = '';
+    protected const TRUE_TO_STRING  = 'true';
+    protected const FALSE_TO_STRING = 'false';
+    protected const NAN_TO_STRING   = 'nan';
+    protected const INF_TO_STRING   = 'inf';
+
     public function match(mixed $value, Context $context): bool
     {
         return \is_string($value);
@@ -21,14 +27,42 @@ public function match(mixed $value, Context $context): bool
      */
     public function cast(mixed $value, Context $context): string
     {
-        if ($this->match($value, $context)) {
+        if (\is_string($value)) {
             /** @var string */
             return $value;
         }
 
+        if (!$context->isStrictTypesEnabled()) {
+            return $this->tryCast($value, $context);
+        }
+
         throw InvalidValueException::createFromContext(
             value: $value,
             context: $context,
         );
     }
+
+    /**
+     * @throws InvalidValueException
+     */
+    private function tryCast(mixed $value, Context $context): string
+    {
+        return match (true) {
+            $value === null => static::NULL_TO_STRING,
+            $value === true => static::TRUE_TO_STRING,
+            $value === false => static::FALSE_TO_STRING,
+            \is_float($value) => match (true) {
+                \is_nan($value) => static::NAN_TO_STRING,
+                \is_infinite($value) => ($value >= 0 ? '' : '-') . static::INF_TO_STRING,
+                default => (string) $value,
+            },
+            \is_int($value),
+            $value instanceof \Stringable => (string) $value,
+            $value instanceof \BackedEnum => (string) $value->value,
+            default => throw InvalidValueException::createFromContext(
+                value: $value,
+                context: $context,
+            ),
+        };
+    }
 }

tests/Feature/Type/string.feature

@@ -13,6 +13,7 @@ Feature: Checking the "StringType" type behavior
             | 42         | false      |
             | 42.1       | false      |
             | INF        | false      |
+            | -INF       | false      |
             | NAN        | false      |
             | "string"   | true       |
             | null       | false      |
@@ -21,9 +22,25 @@ Feature: Checking the "StringType" type behavior
             | true       | false      |
             | false      | false      |
 
-    Scenario Outline: Casting "<value>" by the StringType
+    Scenario Outline: Normalize "<value>" by the StringType
         When normalize
         Then cast of "<value>" must return <result>
+        Examples:
+            | value                | result                              |
+            | 42                   | "42"                                |
+            | -9223372036854775808 | "-9.2233720368548E+18"              |
+            | 42.1                 | "42.1"                              |
+            | INF                  | "inf"                               |
+            | -INF                 | "-inf"                              |
+            | NAN                  | "nan"                               |
+            | "string"             | "string"                            |
+            | null                 | ""                                  |
+            | (object)[]           | <error: Passed value {} is invalid> |
+            | []                   | <error: Passed value [] is invalid> |
+            | true                 | "true"                              |
+            | false                | "false"                             |
+
+    Scenario Outline: Denormalize "<value>" by the StringType
         When denormalize
         Then cast of "<value>" must return <result>
         Examples:
@@ -32,6 +49,7 @@ Feature: Checking the "StringType" type behavior
             | -9223372036854775808 | <error: Passed value -9.2233720368548E+18 is invalid> |
             | 42.1                 | <error: Passed value 42.1 is invalid>                 |
             | INF                  | <error: Passed value INF is invalid>                  |
+            | -INF                 | <error: Passed value -INF is invalid>                 |
             | NAN                  | <error: Passed value NAN is invalid>                  |
             | "string"             | "string"                                              |
             | null                 | <error: Passed value null is invalid>                 |