Carry the renderWhenEmpty flag throughout

This is getting ugly. Mutable classes are a nightmare. We'll fix this in
another issue.

Author: jeffgbutler

src/main/java/org/mybatis/dynamic/sql/where/condition/IsIn.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -51,7 +51,9 @@ public String renderCondition(String columnName, Stream<String> placeholders) {
      * @return new condition with the specified transformer
      */
     public IsIn<T> then(UnaryOperator<Stream<T>> valueStreamTransformer) {
-        return new IsIn<>(values, valueStreamTransformer);
+        IsIn<T> answer = new IsIn<>(values, valueStreamTransformer);
+        answer.renderWhenEmpty = renderWhenEmpty;
+        return answer;
     }
 
     public static <T> IsIn<T> of(Collection<T> values) {

src/main/java/org/mybatis/dynamic/sql/where/condition/IsInCaseInsensitive.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -50,7 +50,9 @@ public String renderCondition(String columnName, Stream<String> placeholders) {
      * @return new condition with the specified transformer
      */
     public IsInCaseInsensitive then(UnaryOperator<Stream<String>> valueStreamTransformer) {
-        return new IsInCaseInsensitive(values, valueStreamTransformer);
+        IsInCaseInsensitive answer = new IsInCaseInsensitive(values, valueStreamTransformer);
+        answer.renderWhenEmpty = renderWhenEmpty;
+        return answer;
     }
 
     public static IsInCaseInsensitive of(Collection<String> values) {

src/main/java/org/mybatis/dynamic/sql/where/condition/IsNotIn.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -52,7 +52,9 @@ public String renderCondition(String columnName, Stream<String> placeholders) {
      * @return new condition with the specified transformer
      */
     public IsNotIn<T> then(UnaryOperator<Stream<T>> valueStreamTransformer) {
-        return new IsNotIn<>(values, valueStreamTransformer);
+        IsNotIn<T> answer = new IsNotIn<>(values, valueStreamTransformer);
+        answer.renderWhenEmpty = renderWhenEmpty;
+        return answer;
     }
 
     public static <T> IsNotIn<T> of(Collection<T> values) {

src/main/java/org/mybatis/dynamic/sql/where/condition/IsNotInCaseInsensitive.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -51,7 +51,9 @@ public String renderCondition(String columnName, Stream<String> placeholders) {
      * @return new condition with the specified transformer
      */
     public IsNotInCaseInsensitive then(UnaryOperator<Stream<String>> valueStreamTransformer) {
-        return new IsNotInCaseInsensitive(values, valueStreamTransformer);
+        IsNotInCaseInsensitive answer = new IsNotInCaseInsensitive(values, valueStreamTransformer);
+        answer.renderWhenEmpty = renderWhenEmpty;
+        return answer;
     }
 
     public static IsNotInCaseInsensitive of(Collection<String> values) {