JS: decomposition of vars

js/js.inliner/src/org/jetbrains/kotlin/js/inline/ExpressionDecomposer.kt

@@ -76,6 +76,25 @@ class ExpressionDecomposer private (
         }
     }
 
+    // TODO: add test case (after KT-7371 fix): var a = foo(), b = foo() + inlineBar()
+    override fun visit(x: JsVars, ctx: JsContext<*>): Boolean {
+        val vars = x.getVars()
+        var prevVars = SmartList<JsVars.JsVar>()
+
+        for (jsVar in vars) {
+            if (jsVar in containsExtractable && prevVars.isNotEmpty()) {
+                addStatement(JsVars(prevVars, x.isMultiline()))
+                prevVars = SmartList<JsVars.JsVar>()
+            }
+
+            jsVar.initExpression = accept(jsVar.initExpression)
+            prevVars.add(jsVar)
+        }
+
+        vars.clear()
+        vars.addAll(prevVars)
+        return false
+    }
 
     override fun visit(x: JsWhile, ctx: JsContext<*>): Boolean {
         x.process(true)

js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/astUtils.kt

@@ -98,3 +98,7 @@ public var JsBinaryOperation.arg2: JsExpression
 
 public val JsBinaryOperation.operator: JsBinaryOperator
     get() = getOperator()
+
+public var JsVars.JsVar.initExpression: JsExpression?
+    get() = getInitExpression()
+    set(value) = setInitExpression(value)

js/js.translator/testData/inlineEvaluationOrder/cases/multiDeclaration.kt

@@ -0,0 +1,19 @@
+package foo
+
+// CHECK_NOT_CALLED: component2
+
+class A(val x: Int, val y: Int)
+
+fun A.component1(): Int = fizz(x)
+
+inline
+fun A.component2(): Int = buzz(y)
+
+fun box(): String {
+    val (a, b) = A(1, 2)
+    assertEquals(a, 1)
+    assertEquals(b, 2)
+    assertEquals("fizz(1);buzz(2);", pullLog())
+
+    return "OK"
+}

js/js.translator/testData/inlineEvaluationOrder/cases/multiDeclarationComplex.kt

@@ -0,0 +1,33 @@
+package foo
+
+// CHECK_NOT_CALLED: component2
+// CHECK_NOT_CALLED: component3
+// CHECK_NOT_CALLED: component5
+
+class A(val a: Int, val b: Int, val c: Int, val d: Int, val e: Int)
+
+fun A.component1(): Int = fizz(a)
+
+inline
+fun A.component2(): Int = buzz(b)
+
+inline
+fun A.component3(): Int = buzz(c)
+
+fun A.component4(): Int = fizz(d)
+
+inline
+fun A.component5(): Int = buzz(e)
+
+fun box(): String {
+    val (a, b, c, d, e) = A(1, 2, 3, 4, 5)
+
+    assertEquals(1, a)
+    assertEquals(2, b)
+    assertEquals(3, c)
+    assertEquals(4, d)
+    assertEquals(5, e)
+    assertEquals("fizz(1);buzz(2);buzz(3);fizz(4);buzz(5);", pullLog())
+
+    return "OK"
+}