From a42bc40b1679cec5cb5adec3adde19d3ea2fb917 Mon Sep 17 00:00:00 2001
From: Yoshiya Hinosawa <stibium121@gmail.com>
Date: Wed, 26 Jun 2024 18:39:48 +0900
Subject: [PATCH] test(csv): improve stringify testing

---
 csv/stringify.ts      |  4 +++-
 csv/stringify_test.ts | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/csv/stringify.ts b/csv/stringify.ts
index 10a9703e9e56..705533f3d23b 100644
--- a/csv/stringify.ts
+++ b/csv/stringify.ts
@@ -218,7 +218,9 @@ function getValuesFromItem(
       let value: unknown = item;
 
       for (const prop of column.prop) {
-        if (typeof value !== "object" || value === null) continue;
+        if (typeof value !== "object" || value === null) {
+          continue;
+        }
         if (Array.isArray(value)) {
           if (typeof prop === "number") value = value[prop];
           else {
diff --git a/csv/stringify_test.ts b/csv/stringify_test.ts
index 9671829df506..77e4bc14b777 100644
--- a/csv/stringify_test.ts
+++ b/csv/stringify_test.ts
@@ -275,6 +275,17 @@ Deno.test({
         },
       },
     );
+    await t.step(
+      {
+        name: "Column: array string accessor via prop field",
+        fn() {
+          const columns = [{ prop: ["msg", "value"] }];
+          const data = [{ msg: { value: "foo" } }, { msg: { value: "bar" } }];
+          const output = `value${CRLF}foo${CRLF}bar${CRLF}`;
+          assertEquals(stringify(data, { columns }), output);
+        },
+      },
+    );
     await t.step(
       {
         name: "Explicit header",
@@ -367,6 +378,18 @@ Deno.test({
         },
       },
     );
+    await t.step(
+      {
+        name: "The case when the entire item is null",
+        fn() {
+          const columns = [0];
+          const data = [null, null];
+          const output = `0${CRLF}${CRLF}${CRLF}`;
+          // deno-lint-ignore no-explicit-any
+          assertEquals(stringify(data as any, { columns }), output);
+        },
+      },
+    );
     await t.step(
       {
         name: "Targeted value: hex number",
@@ -510,6 +533,16 @@ Deno.test({
         assertEquals(stringify(data), output);
       },
     });
+    await t.step({
+      name: "The case when each item is single data, no columns",
+      fn() {
+        const data = [1, 2, 3, 4, 5, 6];
+        const output = `1${CRLF}2${CRLF}3${CRLF}4${CRLF}5${CRLF}6${CRLF}`;
+
+        // deno-lint-ignore no-explicit-any
+        assertEquals(stringify(data as any), output);
+      },
+    });
     await t.step(
       {
         name: "byte-order mark with bom=true",