Place Char constants into builtin Char companion object.

compiler/testData/builtin-classes.txt

@@ -233,6 +233,18 @@ public final class Char : kotlin.Comparable<kotlin.Char> {
 
     public companion object Companion {
         /*primary*/ private constructor Companion()
+        public const final val MAX_HIGH_SURROGATE: kotlin.Char
+            public final fun <get-MAX_HIGH_SURROGATE>(): kotlin.Char
+        public const final val MAX_LOW_SURROGATE: kotlin.Char
+            public final fun <get-MAX_LOW_SURROGATE>(): kotlin.Char
+        public const final val MAX_SURROGATE: kotlin.Char
+            public final fun <get-MAX_SURROGATE>(): kotlin.Char
+        public const final val MIN_HIGH_SURROGATE: kotlin.Char
+            public final fun <get-MIN_HIGH_SURROGATE>(): kotlin.Char
+        public const final val MIN_LOW_SURROGATE: kotlin.Char
+            public final fun <get-MIN_LOW_SURROGATE>(): kotlin.Char
+        public const final val MIN_SURROGATE: kotlin.Char
+            public final fun <get-MIN_SURROGATE>(): kotlin.Char
     }
 }
 

core/builtins/native/kotlin/Char.kt

@@ -21,7 +21,6 @@ package kotlin
  * On the JVM, non-nullable values of this type are represented as values of the primitive type `char`.
  */
 public class Char private () : Comparable<Char> {
-    companion object {}
 
     /**
      * Compares this value with the specified value for order.
@@ -60,5 +59,38 @@ public class Char private () : Comparable<Char> {
     public override fun toFloat(): Float
     /** Returns the value of this character as a `Double`. */
     public override fun toDouble(): Double
+
+    companion object {
+        /**
+         * The minimum value of a Unicode high-surrogate code unit.
+         */
+        public const val MIN_HIGH_SURROGATE: Char = '\uD800'
+
+        /**
+         * The maximum value of a Unicode high-surrogate code unit.
+         */
+        public const val MAX_HIGH_SURROGATE: Char = '\uDBFF'
+
+        /**
+         * The minimum value of a Unicode low-surrogate code unit.
+         */
+        public const val MIN_LOW_SURROGATE: Char = '\uDC00'
+
+        /**
+         * The maximum value of a Unicode low-surrogate code unit.
+         */
+        public const val MAX_LOW_SURROGATE: Char = '\uDFFF'
+
+        /**
+         * The minimum value of a Unicode surrogate code unit.
+         */
+        public const val MIN_SURROGATE: Char = MIN_HIGH_SURROGATE
+
+        /**
+         * The maximum value of a Unicode surrogate code unit.
+         */
+        public const val MAX_SURROGATE: Char = MAX_LOW_SURROGATE
+    }
+
 }
 

core/runtime.jvm/src/kotlin/jvm/internal/PrimitiveCompanionObjects.kt

@@ -53,7 +53,14 @@ private object ByteCompanionObject {
 }
 
 
-private object CharCompanionObject {}
+private object CharCompanionObject {
+    public const val MIN_HIGH_SURROGATE: Char = '\uD800'
+    public const val MAX_HIGH_SURROGATE: Char = '\uDBFF'
+    public const val MIN_LOW_SURROGATE: Char = '\uDC00'
+    public const val MAX_LOW_SURROGATE: Char = '\uDFFF'
+    public const val MIN_SURROGATE: Char = MIN_HIGH_SURROGATE
+    public const val MAX_SURROGATE: Char = MAX_LOW_SURROGATE
+}
 
 private object StringCompanionObject {}
 private object EnumCompanionObject {}

js/js.libraries/src/internal/primitiveCompanionObjects.kt

@@ -52,7 +52,14 @@ private object ByteCompanionObject {
     val MAX_VALUE: Byte = 127
 }
 
-private object CharCompanionObject {}
+private object CharCompanionObject {
+    public const val MIN_HIGH_SURROGATE: Char = '\uD800'
+    public const val MAX_HIGH_SURROGATE: Char = '\uDBFF'
+    public const val MIN_LOW_SURROGATE: Char = '\uDC00'
+    public const val MAX_LOW_SURROGATE: Char = '\uDFFF'
+    public const val MIN_SURROGATE: Char = MIN_HIGH_SURROGATE
+    public const val MAX_SURROGATE: Char = MAX_LOW_SURROGATE
+}
 
 private object StringCompanionObject {}
 private object EnumCompanionObject {}

libraries/stdlib/src/kotlin/text/Char.kt

@@ -61,35 +61,41 @@ public fun Char.isSurrogate(): Boolean = this in Char.MIN_SURROGATE..Char.MAX_SU
 /**
  * The minimum value of a Unicode high-surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MIN_HIGH_SURROGATE: Char
     get() = '\uD800'
 
 /**
  * The maximum value of a Unicode high-surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MAX_HIGH_SURROGATE: Char
     get() = '\uDBFF'
 
 /**
  * The minimum value of a Unicode low-surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MIN_LOW_SURROGATE: Char
     get() = '\uDC00'
 
 /**
  * The maximum value of a Unicode low-surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MAX_LOW_SURROGATE: Char
     get() = '\uDFFF'
 
 /**
  * The minimum value of a Unicode surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MIN_SURROGATE: Char
     get() = MIN_HIGH_SURROGATE
 
 /**
  * The maximum value of a Unicode surrogate code unit.
  */
+@Deprecated("Provided for binary compatibility", level = DeprecationLevel.HIDDEN)
 public val Char.Companion.MAX_SURROGATE: Char
     get() = MAX_LOW_SURROGATE