Fix conversion of assignment as expression in J2K

Blockless if's and so with assignment as expression inside
should turn into blockful
 #KT-16816 fixed

j2k/src/org/jetbrains/kotlin/j2k/ast/Expressions.kt

@@ -33,6 +33,8 @@ class ArrayAccessExpression(val expression: Expression, val index: Expression, v
 
 open class AssignmentExpression(val left: Expression, val right: Expression, val op: Operator) : Expression() {
 
+    fun isMultiAssignment() = right is AssignmentExpression
+
     fun appendAssignment(builder: CodeBuilder, left: Expression, right: Expression) {
         builder.appendOperand(this, left).append(" ").append(op).append(" ").appendOperand(this, right)
     }

j2k/src/org/jetbrains/kotlin/j2k/ast/Statements.kt

@@ -65,9 +65,9 @@ class IfStatement(
     private val brAfterElse = if (singleLine || elseStatement is IfStatement) " " else "\n"
 
     override fun generateCode(builder: CodeBuilder) {
-        builder append "if (" append condition append ")" append br append thenStatement
+        builder append "if (" append condition append ")" append br append thenStatement.wrapToBlockIfRequired()
         if (!elseStatement.isEmpty) {
-            builder append br append "else" append brAfterElse append elseStatement
+            builder append br append "else" append brAfterElse append elseStatement.wrapToBlockIfRequired()
         }
     }
 }
@@ -78,7 +78,7 @@ class WhileStatement(val condition: Expression, val body: Element, singleLine: B
     private val br = if (singleLine) " " else "\n"
 
     override fun generateCode(builder: CodeBuilder) {
-        builder append "while (" append condition append ")" append br append body
+        builder append "while (" append condition append ")" append br append body.wrapToBlockIfRequired()
     }
 }
 
@@ -86,7 +86,7 @@ class DoWhileStatement(val condition: Expression, val body: Element, singleLine:
     private val br = if (singleLine) " " else "\n"
 
     override fun generateCode(builder: CodeBuilder) {
-        builder append "do" append br append body append br append "while (" append condition append ")"
+        builder append "do" append br append body.wrapToBlockIfRequired() append br append "while (" append condition append ")"
     }
 }
 
@@ -105,7 +105,7 @@ class ForeachStatement(
         if (explicitVariableType != null) {
             builder append ":" append explicitVariableType
         }
-        builder append " in " append collection append ")" append br append body
+        builder append " in " append collection append ")" append br append body.wrapToBlockIfRequired()
     }
 }
 

j2k/src/org/jetbrains/kotlin/j2k/ast/Util.kt

@@ -32,6 +32,12 @@ fun CodeBuilder.appendOperand(expression: Expression, operand: Expression, paren
     return this
 }
 
+fun Element.wrapToBlockIfRequired(): Element = when (this) {
+    is AssignmentExpression -> if (isMultiAssignment()) Block.of(this).assignNoPrototype() else this
+    else -> this
+}
+
+
 private fun Expression.precedence(): Int? {
     return when (this) {
         is QualifiedExpression, is MethodCallExpression, is ArrayAccessExpression, is PostfixExpression, is BangBangExpression, is StarExpression -> 0

j2k/testData/fileOrElement/doWhileStatement/whileWithAssignmentAsExpression.java

@@ -0,0 +1,7 @@
+public class SomeClass {
+    int a;
+    int b;
+    void doSomeWhile(int i) {
+        do a = b = i; while (i < 0)
+    }
+}

j2k/testData/fileOrElement/doWhileStatement/whileWithAssignmentAsExpression.kt

@@ -0,0 +1,10 @@
+class SomeClass {
+    internal var a: Int = 0
+    internal var b: Int = 0
+    internal fun doSomeWhile(i: Int) {
+        do {
+            b = i
+            a = b
+        } while (i < 0)
+    }
+}

j2k/testData/fileOrElement/for/assignmentAsExpressionInBody.java

@@ -0,0 +1,7 @@
+public class SomeClass {
+    void doSomeFor() {
+        int a,b;
+        for (int i = 0; i < 10; i++)
+            a = b = i;
+    }
+}

j2k/testData/fileOrElement/for/assignmentAsExpressionInBody.kt

@@ -0,0 +1,10 @@
+class SomeClass {
+    internal fun doSomeFor() {
+        var a: Int
+        var b: Int
+        for (i in 0..9) {
+            b = i
+            a = b
+        }
+    }
+}

j2k/testData/fileOrElement/ifStatement/assignmentAsExpressionInIf.java

@@ -0,0 +1,9 @@
+public class SomeClass {
+    void doSomeIf(int i) {
+        int a,b,c
+        if (i < 0)
+            a = b = i;
+        else
+            b = c = i;
+    }
+}

j2k/testData/fileOrElement/ifStatement/assignmentAsExpressionInIf.kt

@@ -0,0 +1,14 @@
+class SomeClass {
+    internal fun doSomeIf(i: Int) {
+        val a: Int
+        val b: Int
+        val c: Int
+        if (i < 0) {
+            b = i
+            a = b
+        } else {
+            c = i
+            b = c
+        }
+    }
+}

j2k/testData/fileOrElement/whileStatement/whileWithAssignmentAsExpression.java

@@ -0,0 +1,8 @@
+public class SomeClass {
+    int a;
+    int b;
+    void doSomeWhile(int i) {
+        while (i < 0)
+            a = b = i;
+    }
+}

j2k/testData/fileOrElement/whileStatement/whileWithAssignmentAsExpression.kt

@@ -0,0 +1,10 @@
+class SomeClass {
+    internal var a: Int = 0
+    internal var b: Int = 0
+    internal fun doSomeWhile(i: Int) {
+        while (i < 0) {
+            b = i
+            a = b
+        }
+    }
+}

j2k/tests/org/jetbrains/kotlin/j2k/JavaToKotlinConverterForWebDemoTestGenerated.java

@@ -1733,6 +1733,12 @@ public class JavaToKotlinConverterForWebDemoTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/doWhileStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("whileWithAssignmentAsExpression.java")
+        public void testWhileWithAssignmentAsExpression() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/doWhileStatement/whileWithAssignmentAsExpression.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("whileWithBlock.java")
         public void testWhileWithBlock() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/doWhileStatement/whileWithBlock.java");
@@ -2108,6 +2114,12 @@ public class JavaToKotlinConverterForWebDemoTestGenerated extends AbstractJavaTo
             doTest(fileName);
         }
 
+        @TestMetadata("assignmentAsExpressionInBody.java")
+        public void testAssignmentAsExpressionInBody() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/for/assignmentAsExpressionInBody.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("commonCaseForTest.java")
         public void testCommonCaseForTest() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/for/commonCaseForTest.java");
@@ -2699,6 +2711,12 @@ public class JavaToKotlinConverterForWebDemoTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/ifStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("assignmentAsExpressionInIf.java")
+        public void testAssignmentAsExpressionInIf() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/ifStatement/assignmentAsExpressionInIf.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("elseIf.java")
         public void testElseIf() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/ifStatement/elseIf.java");
@@ -5018,6 +5036,12 @@ public class JavaToKotlinConverterForWebDemoTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/whileStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("whileWithAssignmentAsExpression.java")
+        public void testWhileWithAssignmentAsExpression() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/whileStatement/whileWithAssignmentAsExpression.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("whileWithBlock.java")
         public void testWhileWithBlock() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/whileStatement/whileWithBlock.java");

j2k/tests/org/jetbrains/kotlin/j2k/JavaToKotlinConverterSingleFileTestGenerated.java

@@ -1733,6 +1733,12 @@ public class JavaToKotlinConverterSingleFileTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/doWhileStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("whileWithAssignmentAsExpression.java")
+        public void testWhileWithAssignmentAsExpression() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/doWhileStatement/whileWithAssignmentAsExpression.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("whileWithBlock.java")
         public void testWhileWithBlock() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/doWhileStatement/whileWithBlock.java");
@@ -2108,6 +2114,12 @@ public class JavaToKotlinConverterSingleFileTestGenerated extends AbstractJavaTo
             doTest(fileName);
         }
 
+        @TestMetadata("assignmentAsExpressionInBody.java")
+        public void testAssignmentAsExpressionInBody() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/for/assignmentAsExpressionInBody.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("commonCaseForTest.java")
         public void testCommonCaseForTest() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/for/commonCaseForTest.java");
@@ -2699,6 +2711,12 @@ public class JavaToKotlinConverterSingleFileTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/ifStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("assignmentAsExpressionInIf.java")
+        public void testAssignmentAsExpressionInIf() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/ifStatement/assignmentAsExpressionInIf.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("elseIf.java")
         public void testElseIf() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/ifStatement/elseIf.java");
@@ -5018,6 +5036,12 @@ public class JavaToKotlinConverterSingleFileTestGenerated extends AbstractJavaTo
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("j2k/testData/fileOrElement/whileStatement"), Pattern.compile("^(.+)\\.java$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("whileWithAssignmentAsExpression.java")
+        public void testWhileWithAssignmentAsExpression() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/whileStatement/whileWithAssignmentAsExpression.java");
+            doTest(fileName);
+        }
+
         @TestMetadata("whileWithBlock.java")
         public void testWhileWithBlock() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("j2k/testData/fileOrElement/whileStatement/whileWithBlock.java");