feat: change point with aggregation

Author: bartoval

src/parser/__tests__/change_point.test.ts

@@ -155,6 +155,27 @@ describe('CHANGE_POINT command', () => {
       });
     });
 
+    it('CHANGE_POINT with BY option (multiple fields)', () => {
+      const text = `FROM index | CHANGE_POINT value BY category, long.field.name`;
+      const query = EsqlQuery.fromSrc(text);
+
+      expect(query.ast.commands[1]).toMatchObject({
+        type: 'command',
+        name: 'change_point',
+        args: [
+          { type: 'column', name: 'value' },
+          {
+            type: 'option',
+            name: 'by',
+            args: [
+              { type: 'column', name: 'category' },
+              { type: 'column', name: 'long.field.name' },
+            ],
+          },
+        ],
+      });
+    });
+
     it('parses example query with all options', () => {
       const text = `
         FROM k8s

src/parser/core/cst_to_ast_converter.ts

@@ -1395,6 +1395,20 @@ export class CstToAstConverter {
       command.args.push(option);
     }
 
+    if (ctx.BY()) {
+      const booleanExpressions = (ctx._groupings ?? []).filter((e) => !e.exception);
+      const args = booleanExpressions.map((e) =>
+        this.fromBooleanExpressionToExpressionOrUnknown(e)
+      );
+
+      const byOption = this.toByOption(ctx, args);
+
+      if (byOption) {
+        command.args.push(byOption);
+        command.incomplete ||= byOption.incomplete;
+      }
+    }
+
     return command;
   };