[calcite] branch main updated: [CALCITE-6003] JSON_ARRAY() with no arguments does not unparse correctly

[jhyde]

This is an automated email from the ASF dual-hosted git repository.

jhyde pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/calcite.git


The following commit(s) were added to refs/heads/main by this push:
     new 509e8c1712 [CALCITE-6003] JSON_ARRAY() with no arguments does not 
unparse correctly
509e8c1712 is described below

commit 509e8c171268a0599d2612b74c608989cb1bc2ab
Author: Mihai Budiu <mbu...@gmail.com>
AuthorDate: Tue Sep 26 16:16:41 2023 -0700

    [CALCITE-6003] JSON_ARRAY() with no arguments does not unparse correctly
    
    Signed-off-by: Mihai Budiu <mbu...@gmail.com>
---
 .../calcite/sql/fun/SqlJsonArrayFunction.java      | 23 ++++++++++++----------
 .../apache/calcite/sql/parser/SqlParserTest.java   |  8 ++++++++
 2 files changed, 21 insertions(+), 10 deletions(-)

diff --git 
a/core/src/main/java/org/apache/calcite/sql/fun/SqlJsonArrayFunction.java 
b/core/src/main/java/org/apache/calcite/sql/fun/SqlJsonArrayFunction.java
index f4d26d23e7..a0fa2f2766 100644
--- a/core/src/main/java/org/apache/calcite/sql/fun/SqlJsonArrayFunction.java
+++ b/core/src/main/java/org/apache/calcite/sql/fun/SqlJsonArrayFunction.java
@@ -89,16 +89,19 @@ public class SqlJsonArrayFunction extends SqlFunction {
     }
     writer.endList(listFrame);
 
-    SqlJsonConstructorNullClause nullClause = getEnumValue(call.operand(0));
-    switch (nullClause) {
-    case ABSENT_ON_NULL:
-      writer.keyword("ABSENT ON NULL");
-      break;
-    case NULL_ON_NULL:
-      writer.keyword("NULL ON NULL");
-      break;
-    default:
-      throw new IllegalStateException("unreachable code");
+    if (call.operandCount() > 1) {
+      // If we have only 1 operand the value of 'ON NULL' does not matter.
+      SqlJsonConstructorNullClause nullClause = getEnumValue(call.operand(0));
+      switch (nullClause) {
+      case ABSENT_ON_NULL:
+        writer.keyword("ABSENT ON NULL");
+        break;
+      case NULL_ON_NULL:
+        writer.keyword("NULL ON NULL");
+        break;
+      default:
+        throw new IllegalStateException("unreachable code");
+      }
     }
     writer.endFunCall(frame);
   }
diff --git 
a/testkit/src/main/java/org/apache/calcite/sql/parser/SqlParserTest.java 
b/testkit/src/main/java/org/apache/calcite/sql/parser/SqlParserTest.java
index edda041414..d12b7394c2 100644
--- a/testkit/src/main/java/org/apache/calcite/sql/parser/SqlParserTest.java
+++ b/testkit/src/main/java/org/apache/calcite/sql/parser/SqlParserTest.java
@@ -8762,6 +8762,14 @@ public class SqlParserTest {
             + "FORMAT JSON NULL ON NULL)");
   }
 
+  /** Test case for
+   * <a 
href="https://issues.apache.org/jira/browse/CALCITE-6003";>[CALCITE-6003]
+   * JSON_ARRAY() with no arguments does not unparse correctly</a>. */
+  @Test void testEmptyJsonArray() {
+    expr("json_array()")
+        .ok("JSON_ARRAY()");
+  }
+
   @Test void testJsonArray() {
     expr("json_array('foo')")
         .ok("JSON_ARRAY('foo' ABSENT ON NULL)");