Deprecate contains, indexOf, lastIndexOf functions of Float/DoubleArray #KT-28753

libraries/stdlib/common/src/generated/_Arrays.kt

@@ -550,6 +550,8 @@ public operator fun LongArray.contains(element: Long): Boolean {
 /**
  * Returns `true` if [element] is found in the array.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'any { it == element }' instead to continue using this behavior, or '.asList().contains(element: T)' to get the same search behavior as in a list.", ReplaceWith("any { it == element }"))
+@Suppress("DEPRECATION")
 public operator fun FloatArray.contains(element: Float): Boolean {
     return indexOf(element) >= 0
 }
@@ -557,6 +559,8 @@ public operator fun FloatArray.contains(element: Float): Boolean {
 /**
  * Returns `true` if [element] is found in the array.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'any { it == element }' instead to continue using this behavior, or '.asList().contains(element: T)' to get the same search behavior as in a list.", ReplaceWith("any { it == element }"))
+@Suppress("DEPRECATION")
 public operator fun DoubleArray.contains(element: Double): Boolean {
     return indexOf(element) >= 0
 }
@@ -1474,6 +1478,7 @@ public fun LongArray.indexOf(element: Long): Int {
 /**
  * Returns first index of [element], or -1 if the array does not contain element.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'indexOfFirst { it == element }' instead to continue using this behavior, or '.asList().indexOf(element: T)' to get the same search behavior as in a list.", ReplaceWith("indexOfFirst { it == element }"))
 public fun FloatArray.indexOf(element: Float): Int {
     for (index in indices) {
         if (element == this[index]) {
@@ -1486,6 +1491,7 @@ public fun FloatArray.indexOf(element: Float): Int {
 /**
  * Returns first index of [element], or -1 if the array does not contain element.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'indexOfFirst { it == element }' instead to continue using this behavior, or '.asList().indexOf(element: T)' to get the same search behavior as in a list.", ReplaceWith("indexOfFirst { it == element }"))
 public fun DoubleArray.indexOf(element: Double): Int {
     for (index in indices) {
         if (element == this[index]) {
@@ -2004,6 +2010,7 @@ public fun LongArray.lastIndexOf(element: Long): Int {
 /**
  * Returns last index of [element], or -1 if the array does not contain element.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'indexOfLast { it == element }' instead to continue using this behavior, or '.asList().lastIndexOf(element: T)' to get the same search behavior as in a list.", ReplaceWith("indexOfLast { it == element }"))
 public fun FloatArray.lastIndexOf(element: Float): Int {
     for (index in indices.reversed()) {
         if (element == this[index]) {
@@ -2016,6 +2023,7 @@ public fun FloatArray.lastIndexOf(element: Float): Int {
 /**
  * Returns last index of [element], or -1 if the array does not contain element.
  */
+@Deprecated("The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use 'indexOfLast { it == element }' instead to continue using this behavior, or '.asList().lastIndexOf(element: T)' to get the same search behavior as in a list.", ReplaceWith("indexOfLast { it == element }"))
 public fun DoubleArray.lastIndexOf(element: Double): Int {
     for (index in indices.reversed()) {
         if (element == this[index]) {

libraries/stdlib/test/collections/ArraysTest.kt

@@ -12,7 +12,6 @@ import test.assertTypeEquals
 import test.collections.behaviors.*
 import test.comparisons.STRING_CASE_INSENSITIVE_ORDER
 import test.text.isAsciiLetter
-import kotlin.math.exp
 import kotlin.test.*
 import kotlin.random.Random
 
@@ -503,6 +502,7 @@ class ArraysTest {
         // for each arr with size > 0  arr.average() = arr.sum().toDouble() / arr.size()
     }
 
+    @Suppress("DEPRECATION")
     @Test fun indexOfInPrimitiveArrays() {
         expect(-1) { byteArrayOf(1, 2, 3).indexOf(0) }
         expect(0) { byteArrayOf(1, 2, 3).indexOf(1) }

libraries/tools/kotlin-stdlib-gen/src/templates/Elements.kt

@@ -27,6 +27,10 @@ object Elements : TemplateGroupBase() {
         }
     }
 
+    private fun floatingSearchDeprecationMessage(signature: String, replacement: String): String {
+        return "The function has unclear behavior when searching for NaN or zero values and will be removed soon. Use '$replacement' instead to continue using this behavior, or '.asList().$signature' to get the same search behavior as in a list."
+    }
+
     val f_contains = fn("contains(element: T)") {
         include(Iterables, Sequences, ArraysOfObjects, ArraysOfPrimitives)
     } builder {
@@ -34,12 +38,17 @@ object Elements : TemplateGroupBase() {
 
         doc { "Returns `true` if [element] is found in the ${f.collection}." }
         typeParam("@kotlin.internal.OnlyInputTypes T")
+        if (f == ArraysOfPrimitives && primitive!!.isFloatingPoint()) {
+            val replacement = "any { it == element }"
+            deprecate(Deprecation(floatingSearchDeprecationMessage(signature, replacement), replacement, DeprecationLevel.WARNING))
+            annotation("""@Suppress("DEPRECATION")""")
+        }
         returns("Boolean")
         body(Iterables) {
             """
-                if (this is Collection)
-                    return contains(element)
-                return indexOf(element) >= 0
+            if (this is Collection)
+                return contains(element)
+            return indexOf(element) >= 0
             """
         }
         body(ArraysOfPrimitives, ArraysOfObjects, Sequences) {
@@ -57,6 +66,10 @@ object Elements : TemplateGroupBase() {
         specialFor(Lists) {
             annotation("""@Suppress("EXTENSION_SHADOWED_BY_MEMBER") // false warning, extension takes precedence in some cases""")
         }
+        if (f == ArraysOfPrimitives && primitive!!.isFloatingPoint()) {
+            val replacement = "indexOfFirst { it == element }"
+            deprecate(Deprecation(floatingSearchDeprecationMessage(signature, replacement), replacement, DeprecationLevel.WARNING))
+        }
         returns("Int")
         body {
             """
@@ -117,6 +130,10 @@ object Elements : TemplateGroupBase() {
         specialFor(Lists) {
             annotation("""@Suppress("EXTENSION_SHADOWED_BY_MEMBER") // false warning, extension takes precedence in some cases""")
         }
+        if (f == ArraysOfPrimitives && primitive!!.isFloatingPoint()) {
+            val replacement = "indexOfLast { it == element }"
+            deprecate(Deprecation(floatingSearchDeprecationMessage(signature, replacement), replacement, DeprecationLevel.WARNING))
+        }
         returns("Int")
         body {
             """