feat: add support for named enum variant fields (#15)

tests/struct.rs

@@ -0,0 +1,69 @@
+use std::borrow::Cow;
+
+use serde::Deserialize;
+use serde_inline_default::serde_inline_default;
+use serde_json::json;
+
+#[test]
+fn struct_normal() {
+    fn native_default() -> u32 {
+        69
+    }
+
+    #[serde_inline_default]
+    #[derive(Deserialize)]
+    struct Test {
+        #[serde(default = "native_default")]
+        native: u32,
+        #[serde_inline_default(420)]
+        inline: u32,
+        #[serde_inline_default(-1337)]
+        inline_negative: i32,
+        #[serde_inline_default("string".to_string())]
+        string: String,
+    }
+
+    let test: Test = serde_json::from_value(json!({})).unwrap();
+
+    assert_eq!(test.native, 69);
+    assert_eq!(test.inline, 420);
+    assert_eq!(test.inline_negative, -1337);
+    assert_eq!(test.string, "string".to_string());
+}
+
+#[test]
+fn lifetime() {
+    #[serde_inline_default]
+    #[derive(Deserialize)]
+    struct LifetimeTest<'a> {
+        #[serde_inline_default("test".into())]
+        test_str: Cow<'a, str>,
+    }
+
+    let lifetime_test: LifetimeTest = serde_json::from_value(json!({})).unwrap();
+
+    assert_eq!(lifetime_test.test_str, "test");
+}
+
+#[test]
+#[allow(dead_code)]
+fn conditional_compilation() {
+    #[cfg(debug_assertions)]
+    #[derive(Deserialize)]
+    struct TypeA(u8);
+
+    #[cfg(not(debug_assertions))]
+    #[derive(Deserialize)]
+    struct TypeB(u8);
+
+    #[serde_inline_default]
+    #[derive(Deserialize)]
+    struct Test {
+        #[cfg(debug_assertions)]
+        #[serde_inline_default(TypeA(1))]
+        val_a: TypeA,
+        #[cfg(not(debug_assertions))]
+        #[serde_inline_default(TypeB(1))]
+        val_b: TypeB,
+    }
+}