[Yaml] Add flag to dump NULL as ~

OskarStark · OskarStark · commit 749c11d94c4d · 2019-08-01T09:58:34.000+02:00
diff --git a/src/Symfony/Component/Yaml/CHANGELOG.md b/src/Symfony/Component/Yaml/CHANGELOG.md
@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+4.4.0
+-----
+
+ * Added support to dump `null` as `~` by using the `Yaml::DUMP_NULL_AS_TILDE` flag.
+
 4.3.0
 -----
 
diff --git a/src/Symfony/Component/Yaml/Inline.php b/src/Symfony/Component/Yaml/Inline.php
@@ -33,6 +33,7 @@ class Inline
     private static $objectSupport = false;
     private static $objectForMap = false;
     private static $constantSupport = false;
+    private static $nullAsTilde = false;
 
     /**
      * @param int         $flags
@@ -45,6 +46,7 @@ public static function initialize($flags, $parsedLineNumber = null, $parsedFilen
         self::$objectSupport = (bool) (Yaml::PARSE_OBJECT & $flags);
         self::$objectForMap = (bool) (Yaml::PARSE_OBJECT_FOR_MAP & $flags);
         self::$constantSupport = (bool) (Yaml::PARSE_CONSTANT & $flags);
+        self::$nullAsTilde = (bool) (Yaml::DUMP_NULL_AS_TILDE & $flags);
         self::$parsedFilename = $parsedFilename;
 
         if (null !== $parsedLineNumber) {
@@ -129,7 +131,7 @@ public static function dump($value, int $flags = 0): string
                     throw new DumpException(sprintf('Unable to dump PHP resources in a YAML file ("%s").', get_resource_type($value)));
                 }
 
-                return 'null';
+                return self::dumpNull($flags);
             case $value instanceof \DateTimeInterface:
                 return $value->format('c');
             case \is_object($value):
@@ -155,11 +157,11 @@ public static function dump($value, int $flags = 0): string
                     throw new DumpException('Object support when dumping a YAML file has been disabled.');
                 }
 
-                return 'null';
+                return self::dumpNull($flags);
             case \is_array($value):
                 return self::dumpArray($value, $flags);
             case null === $value:
-                return 'null';
+                return self::dumpNull($flags);
             case true === $value:
                 return 'true';
             case false === $value:
@@ -256,6 +258,15 @@ private static function dumpArray(array $value, int $flags): string
         return sprintf('{ %s }', implode(', ', $output));
     }
 
+    private static function dumpNull(int $flags): string
+    {
+        if (Yaml::DUMP_NULL_AS_TILDE & $flags) {
+            return '~';
+        }
+
+        return 'null';
+    }
+
     /**
      * Parses a YAML scalar.
      *
diff --git a/src/Symfony/Component/Yaml/Tests/DumperTest.php b/src/Symfony/Component/Yaml/Tests/DumperTest.php
@@ -513,6 +513,11 @@ public function testNegativeIndentationThrowsException()
     {
         new Dumper(-4);
     }
+
+    public function testDumpNullAsTilde()
+    {
+        $this->assertSame('{ foo: ~ }', $this->dumper->dump(['foo' => null], 0, 0, Yaml::DUMP_NULL_AS_TILDE));
+    }
 }
 
 class A
diff --git a/src/Symfony/Component/Yaml/Yaml.php b/src/Symfony/Component/Yaml/Yaml.php
@@ -33,6 +33,7 @@ class Yaml
     const PARSE_CONSTANT = 256;
     const PARSE_CUSTOM_TAGS = 512;
     const DUMP_EMPTY_ARRAY_AS_SEQUENCE = 1024;
+    const DUMP_NULL_AS_TILDE = 2048;
 
     /**
      * Parses a YAML file into a PHP value.

Original file line number	Diff line number	Diff line change
`@@ -513,6 +513,11 @@ public function testNegativeIndentationThrowsException()`
`513`	`513`	`{`
`514`	`514`	`new Dumper(-4);`
`515`	`515`	`}`
	`516`	`+`
	`517`	`+ public function testDumpNullAsTilde()`
	`518`	`+ {`
	`519`	`+ $this->assertSame('{ foo: ~ }', $this->dumper->dump(['foo' => null], 0, 0, Yaml::DUMP_NULL_AS_TILDE));`
	`520`	`+ }`
`516`	`521`	`}`
`517`	`522`
`518`	`523`	`class A`