[SPARK-28645][SQL] ParseException is thrown when the window is redefined

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

@@ -815,10 +815,16 @@ class AstBuilder extends SqlBaseBaseVisitor[AnyRef] with SQLConfHelper with Logg
       ctx: WindowClauseContext,
       query: LogicalPlan): LogicalPlan = withOrigin(ctx) {
     // Collect all window specifications defined in the WINDOW clause.
-    val baseWindowMap = ctx.namedWindow.asScala.map {
+    val baseWindowTuples = ctx.namedWindow.asScala.map {
       wCtx =>
         (wCtx.name.getText, typedVisit[WindowSpec](wCtx.windowSpec))
-    }.toMap
+    }
+    baseWindowTuples.groupBy(_._1).foreach { kv =>
+      if (kv._2.size > 1) {
+        throw new ParseException(s"The definition of window '${kv._1}' is repetitive", ctx)
+      }
+    }
+    val baseWindowMap = baseWindowTuples.toMap
 
     // Handle cases like
     // window w1 as (partition by p_mfgr order by p_name

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

@@ -250,4 +250,16 @@ WINDOW w AS (
   ORDER BY salary DESC
   RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING
 )
-ORDER BY department;
+ORDER BY department;
+
+SELECT
+    employee_name,
+    salary,
+    first_value(employee_name) OVER w highest_salary,
+    nth_value(employee_name, 2) OVER w second_highest_salary
+FROM
+    basic_pays
+WINDOW
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 1 FOLLOWING),
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 2 FOLLOWING)
+ORDER BY salary DESC;

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

@@ -1,5 +1,5 @@
 -- Automatically generated by SQLQueryTestSuite
--- Number of queries: 35
+-- Number of queries: 36
 
 
 -- !query
@@ -739,4 +739,38 @@ Gerard Hernandez	SCM	6949	Larry Bott	Pamela Castillo
 George Vanauf	Sales	10563	George Vanauf	Steve Patterson
 Steve Patterson	Sales	9441	George Vanauf	Steve Patterson
 Julie Firrelli	Sales	9181	George Vanauf	Steve Patterson
-Foon Yue Tseng	Sales	6660	George Vanauf	Steve Patterson
+Foon Yue Tseng	Sales	6660	George Vanauf	Steve Patterson
+
+
+-- !query
+SELECT
+    employee_name,
+    salary,
+    first_value(employee_name) OVER w highest_salary,
+    nth_value(employee_name, 2) OVER w second_highest_salary
+FROM
+    basic_pays
+WINDOW
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 1 FOLLOWING),
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 2 FOLLOWING)
+ORDER BY salary DESC
+-- !query schema
+struct<>
+-- !query output
+org.apache.spark.sql.catalyst.parser.ParseException
+
+The definition of window 'w' is repetitive(line 8, pos 0)
+
+== SQL ==
+SELECT
+    employee_name,
+    salary,
+    first_value(employee_name) OVER w highest_salary,
+    nth_value(employee_name, 2) OVER w second_highest_salary
+FROM
+    basic_pays
+WINDOW
+^^^
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 1 FOLLOWING),
+    w AS (ORDER BY salary DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 2 FOLLOWING)
+ORDER BY salary DESC