fix(csv-generate): propagate Web Stream generation errors

packages/csv-generate/lib/stream.js

@@ -15,8 +15,12 @@ const generate = (opts) => {
             chunk = Buffer.from(chunk);
             controller.enqueue(chunk);
           },
-          function () {
-            controller.close();
+          function (err) {
+            if (err) {
+              controller.error(err);
+            } else {
+              controller.close();
+            }
           },
         );
       },

packages/csv-generate/test/api.web_stream.js

@@ -1,8 +1,36 @@
 import "should";
+import assert from "node:assert/strict";
 import { generate as generateStream } from "../lib/stream.js";
 import { generate as generateClassic } from "../lib/index.js";
 
 describe("api stream", function () {
+  it("rejects invalid column values", async function () {
+    const reader = generateStream({
+      length: 1,
+      columns: [() => ({})],
+    }).getReader();
+    const error = {
+      message:
+        "INVALID_VALUE: values returned by column function must be a string, a number or null, got {}",
+    };
+    await Promise.all([
+      assert.rejects(reader.read(), error),
+      assert.rejects(reader.closed, error),
+    ]);
+  });
+
+  it("closes after generating valid values", async function () {
+    const reader = generateStream({
+      length: 1,
+      columns: [() => "a", () => null, () => 1],
+    }).getReader();
+    const { value, done } = await reader.read();
+    assert.equal(done, false);
+    assert.equal(value.toString(), "a,,1");
+    assert.deepEqual(await reader.read(), { value: undefined, done: true });
+    await reader.closed;
+  });
+
   it.skip("perf classic", async function () {
     console.time("classic");
     const generator = generateClassic({