Allow insertSelect with no columns

Author: jeffgbutler

src/main/kotlin/org/mybatis/dynamic/sql/util/kotlin/KotlinSubQueryBuilders.kt

@@ -21,7 +21,6 @@ import org.mybatis.dynamic.sql.SqlColumn
 import org.mybatis.dynamic.sql.select.SelectModel
 import org.mybatis.dynamic.sql.util.Buildable
 import org.mybatis.dynamic.sql.util.Messages
-import java.lang.NullPointerException
 
 @MyBatisDslMarker
 sealed class KotlinBaseSubQueryBuilder : Buildable<SelectModel> {
@@ -42,11 +41,7 @@ sealed class KotlinBaseSubQueryBuilder : Buildable<SelectModel> {
     }
 
     override fun build(): SelectModel =
-        try {
-            selectBuilder!!.build()
-        } catch (e: NullPointerException) {
-            throw KInvalidSQLException(Messages.getString("ERROR.28")) //$NON-NLS-1$
-        }
+        selectBuilder?.build()?: throw KInvalidSQLException(Messages.getString("ERROR.28")) //$NON-NLS-1$
 }
 
 class KotlinSubQueryBuilder : KotlinBaseSubQueryBuilder()
@@ -62,10 +57,7 @@ class KotlinQualifiedSubQueryBuilder : KotlinBaseSubQueryBuilder() {
 typealias InsertSelectCompleter = KotlinInsertSelectSubQueryBuilder.() -> Unit
 
 class KotlinInsertSelectSubQueryBuilder : KotlinBaseSubQueryBuilder() {
-    private var columnList: List<SqlColumn<*>>? = null
-
-    internal fun columnList(): List<SqlColumn<*>> =
-        columnList?: throw KInvalidSQLException(Messages.getString("ERROR.29")) //$NON-NLS-1$
+    internal var columnList: List<SqlColumn<*>>? = null
 
     fun columns(vararg columnList: SqlColumn<*>): Unit = columns(columnList.asList())
 

src/main/kotlin/org/mybatis/dynamic/sql/util/kotlin/model/ModelBuilderFunctions.kt

@@ -79,10 +79,16 @@ fun <T : Any> insertMultiple(rows: Collection<T>, completer: KotlinMultiRowInser
 
 fun insertSelect(table: SqlTable, completer: InsertSelectCompleter): InsertSelectModel =
     with(KotlinInsertSelectSubQueryBuilder().apply(completer)) {
-        SqlBuilder.insertInto(table)
-            .withColumnList(columnList())
-            .withSelectStatement(this)
-            .build()
+        if (columnList == null) {
+            SqlBuilder.insertInto(table)
+                .withSelectStatement(this)
+                .build()
+        } else {
+            SqlBuilder.insertInto(table)
+                .withColumnList(columnList)
+                .withSelectStatement(this)
+                .build()
+        }
     }
 
 @Deprecated("Please switch to the insertBatch statement in the model package")

src/main/resources/org/mybatis/dynamic/sql/util/messages.properties

@@ -44,4 +44,3 @@ ERROR.25=Insert Statements Must Contain an "into" phrase
 ERROR.26=Multiple Row Insert Statements Must Contain an "into" phrase
 ERROR.27=You must specify a "from" clause before any other clauses in a select statement
 ERROR.28=You must specify a select statement in a sub query
-ERROR.29=You must specify a column list in an insert select statement

src/test/kotlin/examples/kotlin/spring/canonical/CanonicalSpringKotlinTest.kt

@@ -28,6 +28,7 @@ import examples.kotlin.spring.canonical.PersonDynamicSqlSupport.occupation
 import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.assertThatExceptionOfType
 import org.junit.jupiter.api.Test
+import org.mybatis.dynamic.sql.exception.InvalidSqlException
 import org.mybatis.dynamic.sql.util.Messages
 import org.mybatis.dynamic.sql.util.kotlin.KInvalidSQLException
 import org.mybatis.dynamic.sql.util.kotlin.elements.`as`
@@ -548,14 +549,34 @@ open class CanonicalSpringKotlinTest {
 
     @Test
     fun testInsertSelectNoColumns() {
-        assertThatExceptionOfType(KInvalidSQLException::class.java).isThrownBy {
+        val insertStatement = insertSelect(person) {
+            select(add(id, constant<Int>("100")), firstName, lastName, birthDate, employed, occupation, addressId) {
+                from(person)
+                orderBy(id)
+            }
+        }
+
+        assertThat(insertStatement.insertStatement).isEqualTo(
+            "insert into Person " +
+                    "select (id + 100), first_name, last_name, birth_date, employed, occupation, address_id " +
+                    "from Person " +
+                    "order by id"
+        )
+        val rows = template.insertSelect(insertStatement)
+        assertThat(rows).isEqualTo(6)
+    }
+
+    @Test
+    fun testInsertSelectEmptyColumnList() {
+        assertThatExceptionOfType(InvalidSqlException::class.java).isThrownBy {
             insertSelect(person) {
+                columns()
                 select(add(id, constant<Int>("100")), firstName, lastName, birthDate, employed, occupation, addressId) {
                     from(person)
                     orderBy(id)
                 }
             }
-        }.withMessage(Messages.getString("ERROR.29")) //$NON-NLS-1$
+        }.withMessage(Messages.getString("ERROR.4")) //$NON-NLS-1$
     }
 
     @Test