addressing PR comments - adding test cases for no branches in fork and chaining fuse after a one-branch fork

pmpailis · pmpailis · commit a8ce7b98953e · 2025-10-20T22:02:24.000+03:00
diff --git a/x-pack/plugin/esql/src/internalClusterTest/java/org/elasticsearch/xpack/esql/action/FuseIT.java b/x-pack/plugin/esql/src/internalClusterTest/java/org/elasticsearch/xpack/esql/action/FuseIT.java
@@ -11,6 +11,7 @@
 import org.elasticsearch.action.support.WriteRequest;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.plugins.Plugin;
+import org.elasticsearch.xpack.esql.plan.logical.fuse.Fuse;
 import org.junit.Before;
 
 import java.util.Collection;
@@ -163,6 +164,30 @@ public void testFuseLinearWithWeightsAndNormalizer() {
         }
     }
 
+    public void testFuseWithSingleFork() {
+        for (Fuse.FuseType type : Fuse.FuseType.values()) {
+            var query = """
+                FROM test METADATA _score, _id, _index
+                | WHERE id > 2
+                | FORK
+                   ( WHERE content:"fox" | SORT _score, _id DESC )
+                | FUSE
+                """ + type.name() + """
+                | SORT _score DESC, _id, _index
+                | EVAL _fork = mv_sort(_fork)
+                | EVAL _score = round(_score, 4)
+                | KEEP id, content, _fork
+                """;
+            try (var resp = run(query)) {
+                assertColumnNames(resp.columns(), List.of("id", "content", "_fork"));
+                assertColumnTypes(resp.columns(), List.of("integer", "keyword", "keyword"));
+                assertThat(getValuesList(resp.values()).size(), equalTo(1));
+                Iterable<Iterable<Object>> expectedValues = List.of(List.of(6, "The quick brown fox jumps over the lazy dog", "fork1"));
+                assertValues(resp.values(), expectedValues);
+            }
+        }
+    }
+
     private void createAndPopulateIndex() {
         var indexName = "test";
         var client = client().admin().indices();
diff --git a/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/parser/StatementParserTests.java b/x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/parser/StatementParserTests.java
@@ -3861,6 +3861,13 @@ public void testForkAllCommands() {
     }
 
     public void testInvalidFork() {
+        expectError("""
+            FROM foo* | FORK
+            """, "line 2:1: mismatched input '<EOF>' expecting '('");
+        expectError("""
+            FROM foo* | FORK ()
+            """, "line 1:19: mismatched input ')'");
+
         expectError("""
             FROM foo*
             | FORK (where true) (where true) (where true) (where true)
