[java-completion] MissingThrowExpressionFixer: avoid completion if it's started on the expression line

Fixes IDEA-367667 Complete current statement action breaks on a new line character

GitOrigin-RevId: fed8b5d8d860f491391413383922c112d9649eff

java/java-frontback-impl/src/com/intellij/codeInsight/editorActions/smartEnter/MissingThrowExpressionFixer.java

@@ -15,9 +15,10 @@ public class MissingThrowExpressionFixer implements Fixer {
     throws IncorrectOperationException {
     if (BasicJavaAstTreeUtil.is(astNode, BASIC_THROW_STATEMENT)) {
       ASTNode expression = BasicJavaAstTreeUtil.getExpression(astNode);
-      if (expression != null &&
-          startLine(editor, astNode) == startLine(editor, expression)) {
-        return;
+      if (expression != null) {
+        int expressionLine = startLine(editor, expression);
+        if (startLine(editor, astNode) == expressionLine) return;
+        if (editor.getDocument().getLineNumber(editor.getCaretModel().getOffset()) == expressionLine) return;
       }
 
       final int startOffset = astNode.getTextRange().getStartOffset();

java/java-frontback-tests/testSrc/com/intellij/codeInsight/AbstractBasicCompleteStatementTest.java

@@ -85,6 +85,8 @@ public abstract class AbstractBasicCompleteStatementTest extends LightPlatformCo
   public void testNoErrors() { doTest(); }
 
   public void testThrow() { doTest(); }
+  
+  public void testThrowTwoLinesSemicolon() { doTest(); }
 
   public void testReturn() { doTest(); }
 

java/java-tests/testData/codeInsight/completeStatement/ThrowTwoLinesSemicolon.java

@@ -0,0 +1,7 @@
+
+class Scratch {
+  public static void main(String[] args) {
+    throw
+      new <caret>RuntimeException("aaa")
+  }
+}

java/java-tests/testData/codeInsight/completeStatement/ThrowTwoLinesSemicolon_after.java

@@ -0,0 +1,7 @@
+
+class Scratch {
+  public static void main(String[] args) {
+      throw
+              new RuntimeException("aaa");
+  }
+}