fix: order parameters by index and not textual value (#239)

Prepared statements with 10 or more parameters would not order the
parameters in the DESCRIBE SQL statement according to the parameter
index, but by the textual value. This could lead to the wrong type for a
parameter to be returned to the client.

src/main/java/com/google/cloud/spanner/pgadapter/statements/IntermediatePreparedStatement.java

@@ -133,10 +133,7 @@ public IntermediatePortalStatement bind(
 
   @Override
   public DescribeMetadata<?> describe() {
-    Set<String> parameters =
-        ImmutableSortedSet.<String>orderedBy(Comparator.comparing(o -> o.substring(1)))
-            .addAll(PARSER.getQueryParameters(this.parsedStatement.getSqlWithoutComments()))
-            .build();
+    Set<String> parameters = extractParameters(this.parsedStatement.getSqlWithoutComments());
 
     ResultSet columnsResultSet = null;
     try {
@@ -195,6 +192,19 @@ public DescribeMetadata<?> describe() {
     }
   }
 
+  /**
+   * Extracts the statement parameters from the given sql string and returns these as a sorted set.
+   * The parameters are ordered by their index and not by the textual value (i.e. "$9" comes before
+   * "$10").
+   */
+  @VisibleForTesting
+  static ImmutableSortedSet<String> extractParameters(String sql) {
+    return ImmutableSortedSet.<String>orderedBy(
+            Comparator.comparing(o -> Integer.valueOf(o.substring(1))))
+        .addAll(PARSER.getQueryParameters(sql))
+        .build();
+  }
+
   /**
    * Transforms a query or DML statement into a SELECT statement that selects the parameters in the
    * statements. Examples:

src/test/java/com/google/cloud/spanner/pgadapter/statements/IntermediateStatementTest.java

@@ -14,6 +14,7 @@
 
 package com.google.cloud.spanner.pgadapter.statements;
 
+import static com.google.cloud.spanner.pgadapter.statements.IntermediatePreparedStatement.extractParameters;
 import static com.google.cloud.spanner.pgadapter.statements.IntermediatePreparedStatement.transformDeleteToSelectParams;
 import static com.google.cloud.spanner.pgadapter.statements.IntermediatePreparedStatement.transformInsertToSelectParams;
 import static com.google.cloud.spanner.pgadapter.statements.IntermediatePreparedStatement.transformUpdateToSelectParams;
@@ -39,9 +40,6 @@
 import com.google.cloud.spanner.pgadapter.ConnectionHandler;
 import com.google.cloud.spanner.pgadapter.metadata.OptionsMetadata;
 import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableSortedSet;
-import java.util.Comparator;
-import java.util.Set;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -177,6 +175,13 @@ public void testTransformInsertValuesToSelectParams() {
         transformInsert(
                 "insert\ninto\nfoo\n(col1,\ncol2  ) values ($1 + $2 + 5, $3 || to_char($4) || coalesce($5, ''))")
             .getSql());
+    assertEquals(
+        "select $1, $2, $3, $4, $5, $6, $7, $8, $9, $10 from "
+            + "(select col1=$1, col2=$2, col3=$3, col4=$4, col5=$5, col6=$6, col7=$7, col8=$8, col9=$9, col10=$10 from foo) p",
+        transformInsert(
+                "insert into foo (col1, col2, col3, col4, col5, col6, col7, col8, col9, col10) "
+                    + "values ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10)")
+            .getSql());
   }
 
   @Test
@@ -225,6 +230,12 @@ public void testTransformUpdateToSelectParams() {
     assertNull(transformUpdate("update foo col1=1"));
     assertNull(transformUpdate("update foo col1=1 hwere col1=2"));
     assertNull(transformUpdate("udpate foo col1=1 where col1=2"));
+
+    assertEquals(
+        "select $1, $2, $3, $4, $5, $6, $7, $8, $9, $10 from (select col1=$1, col2=$2, col3=$3, col4=$4, col5=$5, col6=$6, col7=$7, col8=$8, col9=$9 from foo where id=$10) p",
+        transformUpdate(
+                "update foo set col1=$1, col2=$2, col3=$3, col4=$4, col5=$5, col6=$6, col7=$7, col8=$8, col9=$9  where id=$10")
+            .getSql());
   }
 
   @Test
@@ -236,7 +247,7 @@ public void testTransformDeleteToSelectParams() {
         "select $1, $2 from (select 1 from foo where id=$1 and bar > $2) p",
         transformDelete("delete foo\nwhere id=$1 and bar > $2").getSql());
     assertEquals(
-        "select $1, $2, $3, $4, $5, $6, $7, $8, $9 "
+        "select $1, $2, $3, $4, $5, $6, $7, $8, $9, $10 "
             + "from (select 1 from all_types "
             + "where col_bigint=$1 "
             + "and col_bool=$2 "
@@ -246,7 +257,8 @@ public void testTransformDeleteToSelectParams() {
             + "and col_numeric=$6 "
             + "and col_timestamptz=$7 "
             + "and col_date=$8 "
-            + "and col_varchar=$9"
+            + "and col_varchar=$9 "
+            + "and col_jsonb=$10"
             + ") p",
         transformDelete(
                 "delete "
@@ -259,7 +271,8 @@ public void testTransformDeleteToSelectParams() {
                     + "and col_numeric=$6 "
                     + "and col_timestamptz=$7 "
                     + "and col_date=$8 "
-                    + "and col_varchar=$9")
+                    + "and col_varchar=$9 "
+                    + "and col_jsonb=$10")
             .getSql());
 
     assertNull(transformDelete("delete from foo"));
@@ -268,26 +281,14 @@ public void testTransformDeleteToSelectParams() {
   }
 
   private static Statement transformInsert(String sql) {
-    Set<String> parameters =
-        ImmutableSortedSet.<String>orderedBy(Comparator.comparing(o -> o.substring(1)))
-            .addAll(PARSER.getQueryParameters(sql))
-            .build();
-    return transformInsertToSelectParams(mock(Connection.class), sql, parameters);
+    return transformInsertToSelectParams(mock(Connection.class), sql, extractParameters(sql));
   }
 
   private static Statement transformUpdate(String sql) {
-    Set<String> parameters =
-        ImmutableSortedSet.<String>orderedBy(Comparator.comparing(o -> o.substring(1)))
-            .addAll(PARSER.getQueryParameters(sql))
-            .build();
-    return transformUpdateToSelectParams(sql, parameters);
+    return transformUpdateToSelectParams(sql, extractParameters(sql));
   }
 
   private static Statement transformDelete(String sql) {
-    Set<String> parameters =
-        ImmutableSortedSet.<String>orderedBy(Comparator.comparing(o -> o.substring(1)))
-            .addAll(PARSER.getQueryParameters(sql))
-            .build();
-    return transformDeleteToSelectParams(sql, parameters);
+    return transformDeleteToSelectParams(sql, extractParameters(sql));
   }
 }