#77: fixed review findings

doc/changes/changes-4.0.0.md

@@ -1,4 +1,4 @@
-# SQL Statement Builder 4.0.0, released 2020-07-02
+# SQL Statement Builder 4.0.0, released 2020-07-03
 
 ## Bug Fixes
 

src/main/java/com/exasol/sql/dql/select/FromClause.java

@@ -175,24 +175,24 @@ public FromClause fullOuterJoin(final String name, final String specification) {
      * @return {@code FROM} clause
      */
     public FromClause select(final Select select) {
-        this.innerSelect = select;
+        this.subSelect = select;
         return this;
     }
 
     /**
-     * Check if the {@link FromClause} contains an inner select statement.
+     * Check if the {@link FromClause} contains a sub-select statement.
      * 
-     * @return true if the {@link FromClause} contains an inner select statement
+     * @return true if the {@link FromClause} contains a sub-select statement
      */
-    public boolean hasInnerSelect() {
-        return innerSelect != null;
+    public boolean hasSubSelect() {
+        return this.subSelect != null;
     }
 
     @Override
     public void accept(final SelectVisitor visitor) {
         visitor.visit(this);
-        if (hasInnerSelect()) {
-            this.innerSelect.accept(visitor);
+        if (hasSubSelect()) {
+            this.subSelect.accept(visitor);
         }
         for (final Table table : this.tables) {
             table.accept(visitor);
@@ -201,6 +201,9 @@ public void accept(final SelectVisitor visitor) {
             join.accept(visitor);
         }
         for (final ValueTable valueTable : this.valueTables) {
+            if (hasSubSelect()) {
+                throw new IllegalArgumentException("SELECT statement cannot combine sub-select and value table.");
+            }
             valueTable.accept(visitor);
         }
         visitor.leave(this);

src/main/java/com/exasol/sql/dql/select/rendering/SelectRenderer.java

@@ -42,15 +42,15 @@ public void visit(final DerivedColumn derivedColumn) {
     @Override
     public void visit(final FromClause fromClause) {
         appendKeyWord(" FROM ");
-        if (fromClause.hasInnerSelect()) {
+        if (fromClause.hasSubSelect()) {
             startParenthesis();
         }
         setLastVisited(fromClause);
     }
 
     @Override
-    public void leave(FromClause fromClause) {
-        if (fromClause.hasInnerSelect()) {
+    public void leave(final FromClause fromClause) {
+        if (fromClause.hasSubSelect()) {
             endParenthesis();
         }
         setLastVisited(fromClause);

src/test/java/com/exasol/sql/dql/select/rendering/TestSelectRendering.java

@@ -4,11 +4,14 @@
 import static com.exasol.hamcrest.SqlFragmentRenderResultMatcher.rendersWithConfigTo;
 import static com.exasol.sql.expression.BooleanTerm.eq;
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.junit.Assert.assertThrows;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import com.exasol.sql.StatementFactory;
+import com.exasol.sql.ValueTable;
 import com.exasol.sql.dql.select.Select;
 import com.exasol.sql.expression.*;
 import com.exasol.sql.rendering.StringRendererConfig;
@@ -104,10 +107,23 @@ void testQuotedIdentifiers() {
     }
 
     @Test
-    void testSelectFromSelect() {
+    void testSelectFromSubSelect() {
         final Select innerSelect = StatementFactory.getInstance().select();
         innerSelect.all().from().table("t");
         this.select.all().from().select(innerSelect);
         assertThat(this.select, rendersTo("SELECT * FROM (SELECT * FROM t)"));
     }
+
+    @Test
+    void testSelectFromSubSelectInvalid() {
+        final Select innerSelect = StatementFactory.getInstance().select();
+        innerSelect.all().from().table("t");
+        final ValueTable values = new ValueTable(this.select);
+        this.select.all().from().select(innerSelect).valueTable(values);
+        final SelectRenderer renderer = SelectRenderer.create();
+        final IllegalArgumentException exception = assertThrows(IllegalArgumentException.class,
+                () -> this.select.accept(renderer));
+        assertThat(exception.getMessage(),
+                containsString("SELECT statement cannot combine sub-select and value table"));
+    }
 }