[SPARK-32840][SQL] Invalid interval value can happen to be just adhesive with the unit

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala

@@ -2132,7 +2132,16 @@ class AstBuilder(conf: SQLConf) extends SqlBaseBaseVisitor[AnyRef] with Logging
         val kvs = units.indices.map { i =>
           val u = units(i).getText
           val v = if (values(i).STRING() != null) {
-            string(values(i).STRING())
+            val value = string(values(i).STRING())
+            // SPARK-32840: For invalid cases, e.g. INTERVAL '1 day 2' hour,
+            // INTERVAL 'interval 1' day, we need to check ahead before they are concatenated with
+            // units and become valid ones, e.g. '1 day 2 hour'.
+            // Ideally, we only ensure the value parts don't contain any units here.
+            if (value.exists(Character.isLetter)) {
+              throw new ParseException("Can only use numbers in the interval value part for" +
+                s" multiple unit value pairs interval form, but got invalid value: $value", ctx)
+            }
+            value
           } else {
             values(i).getText
           }

sql/core/src/test/resources/sql-tests/inputs/interval.sql

@@ -206,3 +206,7 @@ select interval '1.2';
 select interval '- 2';
 select interval '1 day -';
 select interval '1 day 1';
+
+select interval '1 day 2' day;
+select interval 'interval 1' day;
+select interval '-\t 1' day;

sql/core/src/test/resources/sql-tests/results/ansi/interval.sql.out

@@ -1,5 +1,5 @@
 -- Automatically generated by SQLQueryTestSuite
--- Number of queries: 107
+-- Number of queries: 110
 
 
 -- !query
@@ -1122,3 +1122,39 @@ Cannot parse the INTERVAL value: 1 day 1(line 1, pos 7)
 == SQL ==
 select interval '1 day 1'
 -------^^^
+
+
+-- !query
+select interval '1 day 2' day
+-- !query schema
+struct<>
+-- !query output
+org.apache.spark.sql.catalyst.parser.ParseException
+
+Can only use numbers in the interval value part for multiple unit value pairs interval form, but got invalid value: 1 day 2(line 1, pos 16)
+
+== SQL ==
+select interval '1 day 2' day
+----------------^^^
+
+
+-- !query
+select interval 'interval 1' day
+-- !query schema
+struct<>
+-- !query output
+org.apache.spark.sql.catalyst.parser.ParseException
+
+Can only use numbers in the interval value part for multiple unit value pairs interval form, but got invalid value: interval 1(line 1, pos 16)
+
+== SQL ==
+select interval 'interval 1' day
+----------------^^^
+
+
+-- !query
+select interval '-\t 1' day
+-- !query schema
+struct<INTERVAL '-1 days':interval>
+-- !query output
+-1 days

sql/core/src/test/resources/sql-tests/results/interval.sql.out

@@ -1,5 +1,5 @@
 -- Automatically generated by SQLQueryTestSuite
--- Number of queries: 107
+-- Number of queries: 110
 
 
 -- !query
@@ -1110,3 +1110,39 @@ Cannot parse the INTERVAL value: 1 day 1(line 1, pos 7)
 == SQL ==
 select interval '1 day 1'
 -------^^^
+
+
+-- !query
+select interval '1 day 2' day
+-- !query schema
+struct<>
+-- !query output
+org.apache.spark.sql.catalyst.parser.ParseException
+
+Can only use numbers in the interval value part for multiple unit value pairs interval form, but got invalid value: 1 day 2(line 1, pos 16)
+
+== SQL ==
+select interval '1 day 2' day
+----------------^^^
+
+
+-- !query
+select interval 'interval 1' day
+-- !query schema
+struct<>
+-- !query output
+org.apache.spark.sql.catalyst.parser.ParseException
+
+Can only use numbers in the interval value part for multiple unit value pairs interval form, but got invalid value: interval 1(line 1, pos 16)
+
+== SQL ==
+select interval 'interval 1' day
+----------------^^^
+
+
+-- !query
+select interval '-\t 1' day
+-- !query schema
+struct<INTERVAL '-1 days':interval>
+-- !query output
+-1 days