Fix groovy multivariable declaration

rewrite-groovy/src/main/java/org/openrewrite/groovy/GroovyParserVisitor.java

@@ -39,9 +39,9 @@
 import org.openrewrite.java.marker.OmitParentheses;
 import org.openrewrite.java.marker.Semicolon;
 import org.openrewrite.java.marker.TrailingComma;
-import org.openrewrite.java.tree.*;
 import org.openrewrite.java.tree.Expression;
 import org.openrewrite.java.tree.Statement;
+import org.openrewrite.java.tree.*;
 import org.openrewrite.marker.Markers;
 
 import java.math.BigDecimal;
@@ -122,7 +122,7 @@ private static boolean isOlderThanGroovy3() {
     private Optional<RedundantDef> maybeRedundantDef(ClassNode type, String name) {
         int saveCursor = cursor;
         Space defPrefix = whitespace();
-        if(source.startsWith("def", cursor)) {
+        if (source.startsWith("def", cursor)) {
             skip("def");
             // The def is redundant only when it is followed by the method's return type
             // I hope no one puts an annotation between "def" and the return type
@@ -1419,6 +1419,10 @@ public void visitNotExpression(NotExpression expression) {
         @Override
         public void visitDeclarationExpression(DeclarationExpression expression) {
             Optional<RedundantDef> redundantDef = maybeRedundantDef(expression.getVariableExpression().getType(), expression.getVariableExpression().getName());
+
+            /* The identifier of this type is one of the following: the name of a type, `final`, `def`, `var` or `,`
+             The latter because MultiVariable declarations are returned as separate `DeclarationExpression` by the
+             Groovy AST */
             TypeTree typeExpr = visitVariableExpressionType(expression.getVariableExpression());
 
             J.VariableDeclarations.NamedVariable namedVariable;
@@ -2077,29 +2081,23 @@ public void visitPrefixExpression(PrefixExpression unary) {
 
         public TypeTree visitVariableExpressionType(VariableExpression expression) {
             JavaType type = typeMapping.type(staticType(((org.codehaus.groovy.ast.expr.Expression) expression)));
+            Space prefix = whitespace();
+            StringBuilder keyword = new StringBuilder();
 
-            if (expression.isDynamicTyped()) {
-                Space prefix = whitespace();
-                String keyword;
-                if (source.substring(cursor).startsWith("final")) {
-                    keyword = "final";
-                } else {
-                    keyword = source.substring(cursor, cursor + 3);
+            if (expression.isDynamicTyped() || source.charAt(cursor) == ',') {
+                while (!Character.isWhitespace(source.charAt(cursor))) {
+                    keyword.append(source.charAt(cursor));
+                    cursor++;
                 }
+            } else {
+                keyword.append(expression.getOriginType().getUnresolvedName());
                 cursor += keyword.length();
-                return new J.Identifier(randomId(),
-                        prefix,
-                        Markers.EMPTY,
-                        emptyList(),
-                        keyword,
-                        type, null);
             }
-            Space prefix = sourceBefore(expression.getOriginType().getUnresolvedName());
             J.Identifier ident = new J.Identifier(randomId(),
                     EMPTY,
                     Markers.EMPTY,
                     emptyList(),
-                    expression.getOriginType().getUnresolvedName(),
+                    keyword.toString(),
                     type, null);
             if (expression.getOriginType().getGenericsTypes() != null) {
                 return new J.ParameterizedType(randomId(), prefix, Markers.EMPTY, ident, visitTypeParameterizations(

rewrite-groovy/src/main/java/org/openrewrite/groovy/GroovyPrinter.java

@@ -295,16 +295,16 @@ public J visitLambda(J.Lambda lambda, PrintOutputCapture<P> p) {
             LambdaStyle ls = lambda.getMarkers().findFirst(LambdaStyle.class)
                     .orElse(new LambdaStyle(null, false, !lambda.getParameters().getParameters().isEmpty()));
             boolean parenthesized = lambda.getParameters().isParenthesized();
-            if(!ls.isJavaStyle()) {
+            if (!ls.isJavaStyle()) {
                 p.append('{');
             }
             visitMarkers(lambda.getParameters().getMarkers(), p);
             visitSpace(lambda.getParameters().getPrefix(), Space.Location.LAMBDA_PARAMETERS_PREFIX, p);
-            if(parenthesized) {
+            if (parenthesized) {
                 p.append('(');
             }
             visitRightPadded(lambda.getParameters().getPadding().getParameters(), JRightPadded.Location.LAMBDA_PARAM, ",", p);
-            if(parenthesized) {
+            if (parenthesized) {
                 p.append(')');
             }
             if (ls.isArrow()) {
@@ -318,7 +318,7 @@ public J visitLambda(J.Lambda lambda, PrintOutputCapture<P> p) {
             } else {
                 visit(lambda.getBody(), p);
             }
-            if(!ls.isJavaStyle()) {
+            if (!ls.isJavaStyle()) {
                 p.append('}');
             }
             afterSyntax(lambda, p);
@@ -358,6 +358,7 @@ public J visitForEachLoop(J.ForEachLoop forEachLoop, PrintOutputCapture<P> p) {
             afterSyntax(forEachLoop, p);
             return forEachLoop;
         }
+
         @Override
         public J visitMethodDeclaration(J.MethodDeclaration method, PrintOutputCapture<P> p) {
             beforeSyntax(method, Space.Location.METHOD_DECLARATION_PREFIX, p);

rewrite-groovy/src/test/java/org/openrewrite/groovy/GroovyVisitorTest.java

@@ -54,4 +54,52 @@ public J visitCompilationUnit(G.CompilationUnit cu, ExecutionContext ctx) {
           )
         );
     }
+
+    @Test
+    void multipleAssignmentsAtOneLine() {
+        rewriteRun(
+          groovy(
+            """
+            def startItem = '|  ', endItem = '  |'
+            def repeatLength = startItem.length() + output.length() + endItem.length()
+            println("\\n" + ("-" * repeatLength) + "\\n" + startItem + output + endItem + "\\n" + ("-" * repeatLength))
+            """
+          )
+        );
+    }
+
+    @Test
+    void multipleAssignmentsAtOneLineSimple() {
+        rewriteRun(
+          groovy(
+            """
+            def a = '1', b = '2'
+            """
+          )
+        );
+    }
+
+    @Test
+    void multipleAssignmentsAtMultipleLineDynamicType() {
+        rewriteRun(
+          groovy(
+            """
+             def a = '1'    ,  
+                b = '2'
+            """
+          )
+        );
+    }
+
+    @Test
+    void multipleAssignmentsAtMultipleLineStaticType() {
+        rewriteRun(
+          groovy(
+            """
+             String a = '1'    ,  
+                b = '2'
+            """
+          )
+        );
+    }
 }