JS: add tests too prove that operator conventions are correctly inlined. Support inlining of invoke operator. See KT-7588

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/BoxJsTestGenerated.java

@@ -3890,6 +3890,12 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("operators.kt")
+        public void testOperators() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inline/operators.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("params.kt")
         public void testParams() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inline/params.kt");
@@ -4541,6 +4547,12 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("operators.kt")
+        public void testOperators() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inlineMultiModule/operators.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("parameterWithDefaultValue.kt")
         public void testParameterWithDefaultValue() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inlineMultiModule/parameterWithDefaultValue.kt");

js/js.translator/src/org/jetbrains/kotlin/js/translate/callTranslator/CallTranslator.kt

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.js.translate.callTranslator
 import com.google.dart.compiler.backend.js.ast.*
 import com.google.dart.compiler.backend.js.ast.metadata.*
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.builtins.isFunctionTypeOrSubtype
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
@@ -106,11 +107,13 @@ private fun translateCall(context: TranslationContext,
             translateFunctionCall(context, resolvedCall.functionCall, resolvedCall.variableCall, ExplicitReceivers(newReceiver))
         } else {
             val dispatchReceiver = CallTranslator.translateGet(context, variableCall, null)
+            val isFunctionType = resolvedCall.variableCall.resultingDescriptor.type.isFunctionTypeOrSubtype
+            val inlineCall = if (isFunctionType) resolvedCall.variableCall else resolvedCall
             if (explicitReceivers.extensionOrDispatchReceiver == null) {
-                translateFunctionCall(context, resolvedCall.functionCall, resolvedCall.variableCall, ExplicitReceivers(dispatchReceiver))
+                translateFunctionCall(context, resolvedCall.functionCall, inlineCall, ExplicitReceivers(dispatchReceiver))
             }
             else {
-                translateFunctionCall(context, resolvedCall.functionCall, resolvedCall.variableCall,
+                translateFunctionCall(context, resolvedCall.functionCall, inlineCall,
                                       ExplicitReceivers(dispatchReceiver, explicitReceivers.extensionOrDispatchReceiver))
             }
         }

js/js.translator/testData/box/inline/operators.kt

@@ -0,0 +1,71 @@
+// CHECK_NOT_CALLED_IN_SCOPE: function=plus_za3lpa$ scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=plus scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=invoke scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=get_za3lpa$ scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=set_vux9f0$ scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=dec scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=minus_za3lpa$ scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=invoke_rksjo2$ scope=test
+
+class A {
+    inline operator fun plus(a: Int) = a + 10
+}
+
+class B
+
+inline operator fun B.plus(b: Int) = b + 20
+
+object O {
+    inline operator fun invoke() = 42
+
+    inline operator fun Int.invoke(other: Int) = this + other
+
+    fun test() = (1200)(34)
+}
+
+object R {
+    inline operator fun get(i: Int) = 99 + i
+}
+
+object S {
+    var lastResult = 0
+
+    inline operator fun set(i: Int, value: Int) {
+        lastResult = i + value
+    }
+}
+
+class N(val value: Int) {
+    inline operator fun minus(other: Int) = N(value - other)
+
+    inline operator fun dec() = N(value - 1)
+}
+
+fun box(): String {
+    var result = A() + 1
+    if (result != 11) return "fail: member operator: $result"
+
+    result = B() + 2
+    if (result != 22) return "fail: extension operator: $result"
+
+    result = O()
+    if (result != 42) return "fail: invoke operator: $result"
+
+    result = O.test()
+    if (result != 1234) return "fail: extension invoke operator: $result"
+
+    result = R[1]
+    if (result != 100) return "fail: get operator: $result"
+
+    S[2] = 3
+    result = S.lastResult
+    if (result != 5) return "fail: set operator: $result"
+
+    var n = N(10)
+    n--
+    if (n.value != 9) return "fail: decrement: ${n.value}"
+    n -= 3
+    if (n.value != 6) return "fail: augmented assignment: ${n.value}"
+
+    return "OK"
+}

js/js.translator/testData/box/inlineMultiModule/operators.kt

@@ -0,0 +1,26 @@
+// MODULE: lib
+// FILE: lib.kt
+
+class A {
+    inline operator fun plus(a: Int) = a + 10
+}
+
+class B
+
+inline operator fun B.plus(b: Int) = b + 20
+
+// MODULE: main(lib)
+// FILE: main.kt
+
+// CHECK_NOT_CALLED_IN_SCOPE: function=plus_za3lpa$ scope=box
+// CHECK_NOT_CALLED_IN_SCOPE: function=plus scope=box
+
+fun box(): String {
+    var result = A() + 1
+    if (result != 11) return "fail: member operator"
+
+    result = B() + 2
+    if (result != 22) return "fail: extension operator"
+
+    return "OK"
+}