[WASM] Support nullable types for external functions

compiler/testData/codegen/boxWasmJsInterop/kotlinToJsAdapters.kt

@@ -0,0 +1,126 @@
+// IGNORE_BACKEND: JS_IR, JS
+
+@JsFun("(x) => { if (x !== 'abc') throw 'error' }")
+external fun notNullString(x: String)
+
+@JsFun("(x) => { if (x !== 'abc') throw 'error' }")
+external fun nullString(x: String?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2String(x: String?)
+
+fun testString() {
+    notNullString("abc")
+    nullString("abc")
+    null2String(null)
+}
+
+external interface ExternRef
+
+@JsFun("(x) => { if (x !== 'abc') throw 'error' }")
+external fun notNullExternRef(x: ExternRef)
+
+@JsFun("(x) => { if (x !== 'abc') throw 'error' }")
+external fun nullExternRef(x: ExternRef?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2ExternRef(x: ExternRef?)
+
+@JsFun("() => 'abc'")
+external fun getExternRef(): ExternRef
+
+fun testExterRef() {
+    val externRef = getExternRef()
+    notNullExternRef(externRef)
+    nullExternRef(externRef)
+    null2ExternRef(null)
+}
+
+class DataRef
+
+@JsFun("(x, y) => { if (x === null) throw 'error' }")
+external fun notNullDataRef(x: DataRef)
+
+@JsFun("(x, y) => { if (x === null) throw 'error' }")
+external fun nullDataRef(x: DataRef?)
+
+@JsFun("(x, y) => { if (x !== null) throw 'error' }")
+external fun null2DataRef(x: DataRef?)
+
+fun testDataRef() {
+    val dataRef = DataRef()
+    notNullDataRef(dataRef)
+    nullDataRef(dataRef)
+    null2DataRef(null)
+}
+
+@JsFun("(x) => { if (x !== 123) throw 'error' }")
+external fun notNullInt(x: Int)
+
+@JsFun("(x) => { if (x !== 123) throw 'error' }")
+external fun nullInt(x: Int?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2Int(x: Int?)
+
+fun testInt() {
+    notNullInt(123)
+    nullInt(123)
+    null2Int(null)
+}
+
+@JsFun("(x) => { if (x !== true) throw 'error' }")
+external fun notNullBoolean(x: Boolean)
+
+@JsFun("(x) => { if (x !== true) throw 'error' }")
+external fun nullBoolean(x: Boolean?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2Boolean(x: Boolean?)
+
+fun testBoolean() {
+    notNullBoolean(true)
+    nullBoolean(true)
+    null2Boolean(null)
+}
+
+@JsFun("(x) => { x == 123 }")
+external fun notNullShort(x: Short)
+
+@JsFun("(x) => { if (x !== 123) throw 'error' }")
+external fun nullShort(x: Short?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2Short(x: Short?)
+
+fun testShort() {
+    notNullShort(123.toShort())
+    nullShort(123.toShort())
+    null2Short(null)
+}
+
+@JsFun("(x) => { if (x !== 123.5) throw 'error' }")
+external fun notNullFloat(x: Float)
+
+@JsFun("(x) => { if (x !== 123.5) throw 'error' }")
+external fun nullFloat(x: Float?)
+
+@JsFun("(x) => { if (x !== null) throw 'error' }")
+external fun null2Float(x: Float?)
+
+fun testFloat() {
+    notNullFloat(123.5f)
+    nullFloat(123.5f)
+    null2Float(null)
+}
+
+fun box(): String {
+    testString()
+    testExterRef()
+    testDataRef()
+    testInt()
+    testBoolean()
+    testShort()
+    testFloat()
+    return "OK"
+}