Add query-expr clause to handle duplicate table keys

compiler/ballerina-lang/src/main/java/org/ballerinalang/model/TreeBuilder.java

@@ -20,6 +20,8 @@
 import org.ballerinalang.model.clauses.DoClauseNode;
 import org.ballerinalang.model.clauses.FromClauseNode;
 import org.ballerinalang.model.clauses.LetClauseNode;
+import org.ballerinalang.model.clauses.OnClauseNode;
+import org.ballerinalang.model.clauses.OnConflictClauseNode;
 import org.ballerinalang.model.clauses.SelectClauseNode;
 import org.ballerinalang.model.clauses.WhereClauseNode;
 import org.ballerinalang.model.tree.AnnotationAttachmentNode;
@@ -165,6 +167,8 @@
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangDoClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangFromClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangLetClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnConflictClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangSelectClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangWhereClause;
 import org.wso2.ballerinalang.compiler.tree.expressions.BLangAnnotAccessExpr;
@@ -731,10 +735,18 @@ public static LetClauseNode createLetClauseNode() {
         return new BLangLetClause();
     }
 
+    public static OnClauseNode createOnClauseNode() {
+        return new BLangOnClause();
+    }
+
     public static SelectClauseNode createSelectClauseNode() {
         return new BLangSelectClause();
     }
 
+    public static OnConflictClauseNode createOnConflictClauseNode() {
+        return new BLangOnConflictClause();
+    }
+
     public static DoClauseNode createDoClauseNode() {
         return new BLangDoClause();
     }

compiler/ballerina-lang/src/main/java/org/ballerinalang/model/clauses/OnClauseNode.java

@@ -0,0 +1,34 @@
+/*
+ *  Copyright (c) 2020, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 Inc. licenses this file to you under the Apache License,
+ *  Version 2.0 (the "License"); you may not use this file except
+ *  in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing,
+ *  software distributed under the License is distributed on an
+ *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ *  KIND, either express or implied.  See the License for the
+ *  specific language governing permissions and limitations
+ *  under the License.
+ */
+
+package org.ballerinalang.model.clauses;
+
+import org.ballerinalang.model.tree.Node;
+import org.ballerinalang.model.tree.expressions.ExpressionNode;
+
+/**
+ * The interface with the APIs to implement the "on" clause.
+ *
+ * @since 1.3.0
+ */
+public interface OnClauseNode extends Node {
+
+    ExpressionNode getExpression();
+
+    void setExpression(ExpressionNode expression);
+}

compiler/ballerina-lang/src/main/java/org/ballerinalang/model/clauses/OnConflictClauseNode.java

@@ -0,0 +1,33 @@
+/*
+ *  Copyright (c) 2020, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
+ *
+ *  WSO2 Inc. licenses this file to you under the Apache License,
+ *  Version 2.0 (the "License"); you may not use this file except
+ *  in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing,
+ *  software distributed under the License is distributed on an
+ *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ *  KIND, either express or implied.  See the License for the
+ *  specific language governing permissions and limitations
+ *  under the License.
+ */
+package org.ballerinalang.model.clauses;
+
+import org.ballerinalang.model.tree.Node;
+import org.ballerinalang.model.tree.expressions.ExpressionNode;
+
+/**
+ * The interface with the APIs to implement the "on conflict" clause.
+ *
+ * @since 1.3.0
+ */
+public interface OnConflictClauseNode extends Node {
+
+    ExpressionNode getExpression();
+
+    void setExpression(ExpressionNode expression);
+}

compiler/ballerina-lang/src/main/java/org/ballerinalang/model/tree/NodeKind.java

@@ -171,6 +171,8 @@ public enum NodeKind {
     WHERE,
     DO,
     LET_CLAUSE,
+    ON_CONFLICT,
+    ON,
 
     /* Types */
     ARRAY_TYPE,

compiler/ballerina-lang/src/main/java/org/ballerinalang/model/tree/expressions/QueryExpressionNode.java

@@ -18,6 +18,8 @@
 
 import org.ballerinalang.model.clauses.FromClauseNode;
 import org.ballerinalang.model.clauses.LetClauseNode;
+import org.ballerinalang.model.clauses.OnClauseNode;
+import org.ballerinalang.model.clauses.OnConflictClauseNode;
 import org.ballerinalang.model.clauses.SelectClauseNode;
 import org.ballerinalang.model.clauses.WhereClauseNode;
 
@@ -34,10 +36,18 @@ public interface QueryExpressionNode extends ExpressionNode {
 
     void addFromClauseNode(FromClauseNode fromClauseNode);
 
+    OnClauseNode getOnClauseNode();
+
+    void setOnClauseNode(OnClauseNode onClauseNode);
+
     SelectClauseNode getSelectClauseNode();
 
     void setSelectClauseNode(SelectClauseNode selectClauseNode);
 
+    OnConflictClauseNode getOnConflictClauseNode();
+
+    void setOnConflictClauseNode(OnConflictClauseNode onConflictClauseNode);
+
     List<? extends WhereClauseNode> getWhereClauseNode();
 
     void addWhereClauseNode(WhereClauseNode whereClauseNode);

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/parser/BLangPackageBuilder.java

@@ -87,6 +87,8 @@
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangDoClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangFromClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangLetClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnConflictClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangSelectClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangWhereClause;
 import org.wso2.ballerinalang.compiler.tree.expressions.BLangAccessExpression;
@@ -281,8 +283,12 @@ public class BLangPackageBuilder {
 
     private Stack<BLangLetClause> letClauseNodeStack = new Stack<>();
 
+    private Stack<BLangOnClause> onClauseNodeStack = new Stack<>();
+
     private Stack<BLangSelectClause> selectClauseNodeStack = new Stack<>();
 
+    private Stack<BLangOnConflictClause> onConflictNodeStack = new Stack<>();
+
     private Stack<BLangWhereClause> whereClauseNodeStack = new Stack<>();
 
     private Stack<BLangDoClause> doClauseNodeStack = new Stack<>();
@@ -1924,11 +1930,17 @@ void createQueryExpr(DiagnosticPos pos, Set<Whitespace> ws) {
         while (letClauseNodeStack.size() > 0) {
             queryExpr.addLetClause(letClauseNodeStack.pop());
         }
+        if (onClauseNodeStack.size() > 0) {
+            queryExpr.setOnClauseNode(onClauseNodeStack.pop());
+        }
         queryExpr.setSelectClauseNode(selectClauseNodeStack.pop());
         Collections.reverse(whereClauseNodeStack);
         while (whereClauseNodeStack.size() > 0) {
             queryExpr.addWhereClauseNode(whereClauseNodeStack.pop());
         }
+        if (onConflictNodeStack.size() > 0) {
+            queryExpr.setOnConflictClauseNode(onConflictNodeStack.pop());
+        }
         addExpressionNode(queryExpr);
     }
 
@@ -2004,6 +2016,14 @@ private void addFromClause(DiagnosticPos pos, Set<Whitespace> ws,
         fromClauseNodeStack.push(fromClause);
     }
 
+    void createOnClause(DiagnosticPos pos, Set<Whitespace> ws) {
+        BLangOnClause onClause = (BLangOnClause) TreeBuilder.createOnClauseNode();
+        onClause.addWS(ws);
+        onClause.pos = pos;
+        onClause.expression = (BLangExpression) this.exprNodeStack.pop();
+        onClauseNodeStack.push(onClause);
+    }
+
     void createSelectClause(DiagnosticPos pos, Set<Whitespace> ws) {
         BLangSelectClause selectClause = (BLangSelectClause) TreeBuilder.createSelectClauseNode();
         selectClause.addWS(ws);
@@ -2012,6 +2032,14 @@ void createSelectClause(DiagnosticPos pos, Set<Whitespace> ws) {
         selectClauseNodeStack.push(selectClause);
     }
 
+    void createOnConflictClause(DiagnosticPos pos, Set<Whitespace> ws) {
+        BLangOnConflictClause onConflictClause = (BLangOnConflictClause) TreeBuilder.createOnConflictClauseNode();
+        onConflictClause.addWS(ws);
+        onConflictClause.pos = pos;
+        onConflictClause.expression = (BLangExpression) this.exprNodeStack.pop();
+        onConflictNodeStack.push(onConflictClause);
+    }
+
     void createWhereClause(DiagnosticPos pos, Set<Whitespace> ws) {
         BLangWhereClause whereClause = (BLangWhereClause) TreeBuilder.createWhereClauseNode();
         whereClause.addWS(ws);

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/parser/BLangParserListener.java

@@ -2807,6 +2807,14 @@ public void exitWhereClause(BallerinaParser.WhereClauseContext ctx) {
         this.pkgBuilder.createWhereClause(getCurrentPos(ctx), getWS(ctx));
     }
 
+    @Override
+    public void exitOnClause(BallerinaParser.OnClauseContext ctx) {
+        if (isInErrorState) {
+            return;
+        }
+        this.pkgBuilder.createOnClause(getCurrentPos(ctx), getWS(ctx));
+    }
+
     @Override
     public void exitSelectClause(BallerinaParser.SelectClauseContext ctx) {
         if (isInErrorState) {
@@ -2816,6 +2824,15 @@ public void exitSelectClause(BallerinaParser.SelectClauseContext ctx) {
         this.pkgBuilder.createSelectClause(getCurrentPos(ctx), getWS(ctx));
     }
 
+    @Override
+    public void exitOnConflictClause(BallerinaParser.OnConflictClauseContext ctx) {
+        if (isInErrorState) {
+            return;
+        }
+
+        this.pkgBuilder.createOnConflictClause(getCurrentPos(ctx), getWS(ctx));
+    }
+
     @Override
     public void exitDoClause(BallerinaParser.DoClauseContext ctx) {
         if (isInErrorState) {

compiler/ballerina-lang/src/main/java/org/wso2/ballerinalang/compiler/parser/NodeCloner.java

@@ -57,6 +57,8 @@
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangDoClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangFromClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangLetClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnClause;
+import org.wso2.ballerinalang.compiler.tree.clauses.BLangOnConflictClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangSelectClause;
 import org.wso2.ballerinalang.compiler.tree.clauses.BLangWhereClause;
 import org.wso2.ballerinalang.compiler.tree.expressions.BLangAccessExpression;
@@ -1286,8 +1288,10 @@ public void visit(BLangQueryExpr source) {
         source.cloneRef = clone;
         clone.fromClauseList = cloneList(source.fromClauseList);
         clone.letClausesList = cloneList(source.letClausesList);
+        clone.onClause = clone(source.onClause);
         clone.selectClause = clone(source.selectClause);
         clone.whereClauseList = cloneList(source.whereClauseList);
+        clone.onConflictClause = clone(source.onConflictClause);
     }
 
     @Override
@@ -1320,6 +1324,14 @@ private List<BLangLetVariable> cloneLetVarDeclarations (List<BLangLetVariable> l
         return cloneDefs;
     }
 
+    @Override
+    public void visit(BLangOnClause source) {
+
+        BLangOnClause clone = new BLangOnClause();
+        source.cloneRef = clone;
+        clone.expression = clone(source.expression);
+    }
+
     @Override
     public void visit(BLangSelectClause source) {
 
@@ -1328,6 +1340,14 @@ public void visit(BLangSelectClause source) {
         clone.expression = clone(source.expression);
     }
 
+    @Override
+    public void visit(BLangOnConflictClause source) {
+
+        BLangOnConflictClause clone = new BLangOnConflictClause();
+        source.cloneRef = clone;
+        clone.expression = clone(source.expression);
+    }
+
     @Override
     public void visit(BLangWhereClause source) {