Initial commit

src/lib.rs

@@ -0,0 +1,94 @@
+use sqlite3_ext::{
+    function::{Context, FunctionOptions},
+    *,
+};
+
+fn add(a: i32, b: i32) -> i32 {
+    a + b
+}
+
+fn add_sqlite(ctx: &mut Context, args: &mut [&mut ValueRef]) -> Result<()> {
+    if args.len() != 2 {
+        return Err(sqlite3_ext::Error::Module(
+            "myadd requires exactly 2 arguments".to_string(),
+        ));
+    }
+    if args[0].value_type() != ValueType::Integer || args[1].value_type() != ValueType::Integer {
+        return Err(sqlite3_ext::Error::Module(
+            "myadd requires both arguments to be an integer".to_string(),
+        ));
+    }
+
+    let a = args[0].get_i32();
+    let b = args[1].get_i32();
+    let result = add(a, b);
+    ctx.set_result(result)?;
+    Ok(())
+}
+
+#[sqlite3_ext_main(persistent)]
+fn init(db: &Connection) -> Result<()> {
+    db.create_scalar_function(
+        "myadd",
+        &FunctionOptions::default()
+            .set_n_args(2)
+            .set_deterministic(true),
+        add_sqlite,
+    )?;
+
+    Ok(())
+}
+
+#[cfg(all(test, feature = "static"))]
+mod test {
+    use super::*;
+    use sqlite3_ext::Error;
+
+    fn setup() -> Result<Database> {
+        let conn = Database::open(":memory:")?;
+        init(&conn)?;
+        Ok(conn)
+    }
+
+    #[test]
+    fn test_working() -> Result<()> {
+        let conn = setup()?;
+        let results: Vec<i64> = conn
+            .prepare("SELECT myadd(10, 20)")?
+            .query(())?
+            .map(|row| Ok(row[0].get_i64()))
+            .collect()?;
+        assert_eq!(results, vec![30]);
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_wrong_arg_number() -> Result<()> {
+        let conn = setup()?;
+        let result = conn.prepare("SELECT myadd(10)");
+        assert_eq!(
+            result.unwrap_err(),
+            Error::Sqlite(
+                1,
+                Some("wrong number of arguments to function myadd()".to_string()),
+            )
+        );
+        Ok(())
+    }
+
+    #[test]
+    fn test_wrong_arg_type() -> Result<()> {
+        let conn = setup()?;
+        let mut statement = conn.prepare("SELECT myadd(10, 'hello!')")?;
+        let result = statement.query(())?.next();
+        assert_eq!(
+            result.unwrap_err(),
+            Error::Sqlite(
+                1,
+                Some("myadd requires both arguments to be an integer".to_string()),
+            )
+        );
+        Ok(())
+    }
+}