Test showing duplicate names in rowIterator are being overwritten

src/workerd/api/sql-test.js

@@ -504,6 +504,37 @@ async function test(storage) {
     assert.equal(getI(), 2);
   }
 
+  // Test joining two tables with overlapping names
+  {
+    sql.exec(`CREATE TABLE abc (a INT, b INT, c INT);`)
+    sql.exec(`CREATE TABLE cde (c INT, d INT, e INT);`)
+    sql.exec(`INSERT INTO abc VALUES (1,2,3),(4,5,6);`)
+    sql.exec(`INSERT INTO cde VALUES (7,8,9),(1,2,3);`)
+    const fullJoin = sql.prepare(`SELECT * FROM abc, cde`)
+
+    // Raw results include both 'c' columns
+    const rawResults = Array.from(fullJoin().raw())
+    assert.equal(rawResults.length, 4)
+    assert.equal(rawResults[0].length, 6)
+    assert.equal(rawResults[1].length, 6)
+    assert.equal(rawResults[2].length, 6)
+    assert.equal(rawResults[3].length, 6)
+
+    // Obj results _should_ preserve full data, but the two 'c' columns are overwriting one another
+    const objResults = Array.from(fullJoin())
+    assert.equal(objResults.length, 4)
+    // TODO: restore
+    //assert.equal(Object.values(objResults[0]).length, 6)
+    //assert.equal(Object.values(objResults[1]).length, 6)
+    //assert.equal(Object.values(objResults[2]).length, 6)
+    //assert.equal(Object.values(objResults[3]).length, 6)
+
+    // Perhaps we should handle collision as so?
+    assert.equal(objResults[0].c, 3) // First use of 'c' in result set
+    assert.equal(objResults[0].c_1, 7) // Second use of 'c' gets suffix with collision count?
+
+  }
+
   await scheduler.wait(1);
 
   // Test for bug where a cursor constructed from a prepared statement didn't have a strong ref