#49: Improved error message for oneof field label

Labels are not allowed for oneof fields.

Author: kshchepanovskyi

src/main/java/io/protostuff/jetbrains/plugin/annotator/ProtoErrorsAnnotator.java

@@ -19,6 +19,7 @@
 import io.protostuff.jetbrains.plugin.psi.GroupNode;
 import io.protostuff.jetbrains.plugin.psi.MessageField;
 import io.protostuff.jetbrains.plugin.psi.MessageNode;
+import io.protostuff.jetbrains.plugin.psi.OneOfNode;
 import io.protostuff.jetbrains.plugin.psi.OptionNode;
 import io.protostuff.jetbrains.plugin.psi.ProtoRootNode;
 import io.protostuff.jetbrains.plugin.psi.RangeNode;
@@ -140,15 +141,27 @@ private void checkDefaultValue(@NotNull OptionNode option, Syntax syntax) {
 
 
     private void checkFieldLabel(FieldNode field, Syntax syntax) {
-        switch (syntax) {
-            case PROTO2:
-                checkFieldLabelProto2(field);
-                break;
-            case PROTO3:
-                checkFieldLabelProto3(field);
-                break;
-            default:
-                throw new IllegalStateException(String.valueOf(syntax));
+        if (field.getParent() instanceof OneOfNode) {
+            checkOneofFieldLabel(field);
+        } else {
+            switch (syntax) {
+                case PROTO2:
+                    checkFieldLabelProto2(field);
+                    break;
+                case PROTO3:
+                    checkFieldLabelProto3(field);
+                    break;
+                default:
+                    throw new IllegalStateException(String.valueOf(syntax));
+            }
+        }
+    }
+
+    private void checkOneofFieldLabel(FieldNode field) {
+        ASTNode fieldLabelNode = field.getFieldLabelNode();
+        if (fieldLabelNode != null) {
+            String message = message("error.illegal.oneof.field.label");
+            markError(field.getFieldLabelNode(), null, message);
         }
     }
 

src/main/resources/io/protostuff/protobuf-jetbrains-plugin/messages/ProtostuffBundle.properties

@@ -27,3 +27,4 @@ error.default.value.not.supported=Default values are not supported in proto3
 error.groups.not.supported=Groups are not supported in proto3
 error.extensions.not.supported=Extensions are not supported in proto3
 error.first.enum.value.should.be.zero=First enum value must be zero in proto3
+error.illegal.oneof.field.label=Oneof field cannot have label

src/test/java/io/protostuff/jetbrains/plugin/annotator/ProtoErrorsAnnotatorTest.java

@@ -14,6 +14,14 @@ protected String getTestDataPath() {
         return "src/test/resources/annotator";
     }
 
+    public void testNormalOneof() {
+        check();
+    }
+
+    public void testIllegalOneofLabel() {
+        check();
+    }
+
     public void testInvalidTagValue() {
         check();
     }

src/test/resources/annotator/IllegalOneofLabel.proto

@@ -0,0 +1,12 @@
+syntax = "proto2";
+
+package annotator;
+
+message TestMessage {
+
+    oneof action {
+        <error descr="Oneof field cannot have label">optional</error> int32 field1 = 1;
+        <error descr="Oneof field cannot have label">required</error> int32 field2 = 2;
+        <error descr="Oneof field cannot have label">repeated</error> int32 field3 = 3;
+    }
+}

src/test/resources/annotator/NormalOneof.proto

@@ -0,0 +1,11 @@
+syntax = "proto2";
+
+package annotator;
+
+message TestMessage {
+
+    oneof action {
+        int32 field1 = 1;
+        int32 field2 = 2;
+    }
+}