Write throw expression parsing (light tree to FIR)

compiler/fir/lightTree/src/org/jetbrains/kotlin/fir/lightTree/converter/ExpressionsConverter.kt

@@ -83,6 +83,7 @@ class ExpressionsConverter(
                 FOR -> convertFor(expression)
                 BREAK, CONTINUE -> convertLoopJump(expression)
                 RETURN -> convertReturn(expression)
+                THROW -> convertThrow(expression)
                 PARENTHESIZED, PROPERTY_DELEGATE, INDICES -> convertExpression(expression.getExpressionInParentheses())
                 THIS_EXPRESSION -> convertThisExpression(expression)
                 SUPER_EXPRESSION -> convertSuperExpression(expression)
@@ -804,6 +805,19 @@ class ExpressionsConverter(
         return result.toReturn(labelName)
     }
 
+    /**
+     * @see org.jetbrains.kotlin.parsing.KotlinExpressionParsing.parseThrow
+     * @see org.jetbrains.kotlin.fir.builder.RawFirBuilder.Visitor.visitThrowExpression
+     */
+    private fun convertThrow(throwExpression: LighterASTNode): FirExpression {
+        var firExpression: FirExpression? = null
+        throwExpression.forEachChildren {
+            if (it.isExpression()) firExpression = getAsFirExpression(it)
+        }
+
+        return FirThrowExpressionImpl(session, null, firExpression ?: FirErrorExpressionImpl(session, null, "Nothing to throw"))
+    }
+
     /**
      * @see org.jetbrains.kotlin.parsing.KotlinExpressionParsing.parseThisExpression
      * @see org.jetbrains.kotlin.fir.builder.RawFirBuilder.Visitor.visitThisExpression

compiler/fir/lightTree/tests/org/jetbrains/kotlin/fir/lightTree/compare/TreesCompareTest.kt

@@ -304,4 +304,21 @@ class TreesCompareTest : AbstractRawFirBuilderTestCase() {
             visitQualifiedAccessExpression = true
         )
     }
+
+    fun testThrowExpression() {
+        compare(
+            stubMode = false,
+            visitAnonymousFunction = true,
+            visitLambdaExpression = true,
+            visitLocalMembers = true,
+            visitVariable = true,
+            visitAnnotation = true,
+            visitFunctionCall = true,
+            visitThrowExpression = true,
+            visitLoops = true,
+            visitConstExpression = true,
+            visitQualifiedAccessExpression = true,
+            visitAnonymousObject = true
+        )
+    }
 }