From 3a53ff4beea88c7b48a75e5d97fa90772e87af34 Mon Sep 17 00:00:00 2001
From: Xiangkai Zeng <xiangkaiz@klavis.ai>
Date: Sat, 20 Jun 2026 06:47:04 +0000
Subject: [PATCH] Add SQLite integration test for #[sqlx(json)] on TEXT columns

Covers reading a JSON-as-TEXT column into a FromRow struct field
annotated with #[sqlx(json)], and the error path where invalid JSON
surfaces as sqlx::Error::ColumnDecode.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 tests/sqlite/derives.rs | 52 ++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 51 insertions(+), 1 deletion(-)

diff --git a/tests/sqlite/derives.rs b/tests/sqlite/derives.rs
index 3491ab8539..3fff26fd42 100644
--- a/tests/sqlite/derives.rs
+++ b/tests/sqlite/derives.rs
@@ -1,5 +1,5 @@
 use sqlx::Sqlite;
-use sqlx_test::test_type;
+use sqlx_test::{new, test_type};
 
 #[derive(Debug, PartialEq, sqlx::Type)]
 #[repr(u32)]
@@ -32,3 +32,53 @@ test_type!(transparent_named<TransparentNamed>(Sqlite,
     "0" == TransparentNamed { field: 0 },
     "23523" == TransparentNamed { field: 23523 },
 ));
+
+// SQLite stores JSON as TEXT. The `#[sqlx(json)]` field attribute lets a struct
+// read such a column into a `serde_json::Value` (or any `Deserialize` type),
+// deserializing it with `serde_json` during decode.
+#[derive(Debug, PartialEq, sqlx::FromRow)]
+struct JsonRow {
+    id: i64,
+    #[sqlx(json)]
+    data: serde_json::Value,
+}
+
+#[sqlx_macros::test]
+async fn it_reads_json_from_text_column() -> anyhow::Result<()> {
+    let mut conn = new::<Sqlite>().await?;
+
+    let row: JsonRow = sqlx::query_as(
+        r#"SELECT 1 AS id, '{"key": "value"}' AS data"#,
+    )
+    .fetch_one(&mut conn)
+    .await?;
+
+    assert_eq!(
+        row,
+        JsonRow {
+            id: 1,
+            data: serde_json::json!({ "key": "value" }),
+        }
+    );
+
+    Ok(())
+}
+
+#[sqlx_macros::test]
+async fn it_surfaces_invalid_json_as_column_decode_error() -> anyhow::Result<()> {
+    let mut conn = new::<Sqlite>().await?;
+
+    let result: Result<JsonRow, sqlx::Error> =
+        sqlx::query_as(r#"SELECT 1 AS id, 'not valid json' AS data"#)
+            .fetch_one(&mut conn)
+            .await;
+
+    match result {
+        Err(sqlx::Error::ColumnDecode { index, .. }) => {
+            assert_eq!(index, "\"data\"");
+        }
+        other => panic!("expected ColumnDecode error, got {other:?}"),
+    }
+
+    Ok(())
+}