[JS IR BE] hashCode, toString, number conversion support

libraries/stdlib/js/irRuntime/core.kt

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin.js
+
+fun equals(obj1: dynamic, obj2: dynamic): Boolean {
+    if (obj1 == null) {
+        return obj2 == null
+    }
+
+    if (obj2 == null) {
+        return false
+    }
+
+    return js("""
+    if (typeof obj1 === "object" && typeof obj1.equals === "function") {
+        return obj1.equals(obj2);
+    }
+
+    if (obj1 !== obj1) {
+        return obj2 !== obj2;
+    }
+
+    if (typeof obj1 === "number" && typeof obj2 === "number") {
+        return obj1 === obj2 && (obj1 !== 0 || 1 / obj1 === 1 / obj2)
+    }
+    return obj1 === obj2;
+    """).unsafeCast<Boolean>()
+}
+
+fun toString(o: dynamic): String = when {
+    o == null -> "null"
+    isArrayish(o) -> "[...]"
+    else -> js("o.toString()").unsafeCast<String>()
+}
+
+// TODO: Simplify, extract kotlin declarations for inner helper functions
+fun hashCode(obj: dynamic): Int {
+    return js(
+        """
+    function hashCode(obj) {
+        if (obj == null) {
+            return 0;
+        }
+        var objType = typeof obj;
+        if ("object" === objType) {
+            return "function" === typeof obj.hashCode ? obj.hashCode() : getObjectHashCode(obj);
+        }
+        if ("function" === objType) {
+            return getObjectHashCode(obj);
+        }
+        if ("number" === objType) {
+            return getNumberHashCode(obj);
+        }
+        if ("boolean" === objType) {
+            return Number(obj)
+        }
+
+        var str = String(obj);
+        return getStringHashCode(str);
+    };
+
+    /** @const */
+    var POW_2_32 = 4294967296;
+    // TODO: consider switching to Symbol type once we are on ES6.
+    /** @const */
+    var OBJECT_HASH_CODE_PROPERTY_NAME = "kotlinHashCodeValue${'$'}";
+
+    function getObjectHashCode(obj) {
+        if (!(OBJECT_HASH_CODE_PROPERTY_NAME in obj)) {
+            var hash = (Math.random() * POW_2_32) | 0; // Make 32-bit singed integer.
+            Object.defineProperty(obj, OBJECT_HASH_CODE_PROPERTY_NAME, { value:  hash, enumerable: false });
+        }
+        return obj[OBJECT_HASH_CODE_PROPERTY_NAME];
+    }
+
+    function getStringHashCode(str) {
+        var hash = 0;
+        for (var i = 0; i < str.length; i++) {
+            var code  = str.charCodeAt(i);
+            hash  = (hash * 31 + code) | 0; // Keep it 32-bit.
+        }
+        return hash;
+    }
+
+    function getNumberHashCode(obj) {
+        if ((obj | 0) === obj) {
+            return obj | 0;
+        }
+        else {
+            bufFloat64[0] = obj;
+            return (bufInt32[highIndex] * 31 | 0) + bufInt32[lowIndex] | 0;
+        }
+    }
+
+    return hashCode(obj);
+    """
+    ).unsafeCast<Int>()
+}