fix: fix JSonExpression, accept Expressions

Make JSonExpression accept Expressions Add Testcase Expose Idents() and Operators() Fixes #1696
JSQLParser · wumpz · Dec 22, 2022 · Aug 16, 2022 · Sep 15, 2022 · Oct 14, 2022
commit 1ce014ac5069af3ec2dfe6cdc62fe130de9c5e1c
diff --git a/src/main/java/net/sf/jsqlparser/expression/JsonExpression.java b/src/main/java/net/sf/jsqlparser/expression/JsonExpression.java
@@ -15,7 +15,6 @@
 import net.sf.jsqlparser.parser.ASTNodeAccessImpl;
 
 public class JsonExpression extends ASTNodeAccessImpl implements Expression {
-
     private Expression expr;
 
     private List<String> idents = new ArrayList<String>();
@@ -34,26 +33,19 @@ public void setExpression(Expression expr) {
         this.expr = expr;
     }
 
-//    public List<String> getIdents() {
-//        return idents;
-//    }
-//
-//    public void setIdents(List<String> idents) {
-//        this.idents = idents;
-//        operators = new ArrayList<String>();
-//        for (String ident : idents) {
-//            operators.add("->");
-//        }
-//    }
-//
-//    public void addIdent(String ident) {
-//        addIdent(ident, "->");
-//    }
     public void addIdent(String ident, String operator) {
         idents.add(ident);
         operators.add(operator);
     }
 
+    public List<String> getIdents() {
+        return idents;
+    }
+
+    public List<String> getOperators() {
+        return operators;
+    }
+
     @Override
     public String toString() {
         StringBuilder b = new StringBuilder();

diff --git a/src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt b/src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt
@@ -3951,11 +3951,11 @@ Expression PrimaryExpression() #PrimaryExpression:
 
         | LOOKAHEAD(3, {!interrupted}) retval=CaseWhenExpression()
 
-        | retval = SimpleJdbcParameter()
+        | LOOKAHEAD(3) retval = SimpleJdbcParameter()
 
-        | LOOKAHEAD(2, {!interrupted}) retval=JdbcNamedParameter()
+        | LOOKAHEAD(2) retval=JdbcNamedParameter()
 
-        | retval=UserVariable()
+        | LOOKAHEAD(3) retval=UserVariable()
 
         | LOOKAHEAD(2, {!interrupted}) retval=NumericBind()
 
@@ -4178,7 +4178,33 @@ JsonExpression JsonExpression() : {
   CastExpression castExpr = null;
 }
 {
-    expr=Column()
+    (
+        LOOKAHEAD(3, {!interrupted}) expr=CaseWhenExpression()
+        |
+        expr = SimpleJdbcParameter()
+        |
+        LOOKAHEAD(2, {!interrupted}) expr=JdbcNamedParameter()
+        |
+        expr=UserVariable()
+        |
+        LOOKAHEAD(JsonFunction(), {!interrupted}) expr = JsonFunction()
+        |
+        LOOKAHEAD(JsonAggregateFunction(), {!interrupted}) expr = JsonAggregateFunction()
+        |
+        LOOKAHEAD(FullTextSearch(), {!interrupted}) expr = FullTextSearch()
+        /* Do not parse Functions as this will result in a major performance loss
+           The Performance related tests will fail.
+        |
+        LOOKAHEAD(Function(), {!interrupted}) expr=Function()
+        */
+        |
+        LOOKAHEAD(2, {!interrupted}) expr=Column()
+        |
+        token=<S_CHAR_LITERAL> { expr = new StringValue(token.image); }
+        |
+        LOOKAHEAD("(" expr=SubSelect() ")", {!interrupted} ) "(" expr=SubSelect() ")"
+    )
+
     ( "::" type=ColDataType() {
             castExpr = new CastExpression();
             castExpr.setUseCastKeyword(false);

diff --git a/src/test/java/net/sf/jsqlparser/statement/select/PostgresTest.java b/src/test/java/net/sf/jsqlparser/statement/select/PostgresTest.java
@@ -10,7 +10,9 @@
 package net.sf.jsqlparser.statement.select;
 
 import net.sf.jsqlparser.JSQLParserException;
+import net.sf.jsqlparser.expression.JsonExpression;
 import net.sf.jsqlparser.test.TestUtils;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 public class PostgresTest {
@@ -41,4 +43,14 @@ public void testExtractFunctionIssue1582() throws JSQLParserException {
                 "              as snijtijd_interval";
         TestUtils.assertSqlCanBeParsedAndDeparsed(sqlStr, true);
     }
+
+    @Test
+    public void testJSonExpressionIssue1696() throws JSQLParserException {
+        String sqlStr="SELECT '{\"key\": \"value\"}'::json -> 'key' AS X";
+        Select select = (Select) TestUtils.assertSqlCanBeParsedAndDeparsed(sqlStr, true);
+
+        PlainSelect plainSelect = (PlainSelect) select.getSelectBody();
+        SelectExpressionItem selectExpressionItem = (SelectExpressionItem) plainSelect.getSelectItems().get(0);
+        Assertions.assertEquals("'key'", selectExpressionItem.getExpression(JsonExpression.class).getIdents().get(0));
+    }
 }