Prototype: wrap MediaType in a UniFFI object to prevent fallback variant breakage

native/kotlin/api/kotlin/src/integrationTest/kotlin/MediaEndpointTest.kt

@@ -5,11 +5,13 @@ import org.junit.jupiter.api.Assertions.assertNull
 import org.junit.jupiter.api.Test
 import uniffi.wp_api.MediaCreateParams
 import uniffi.wp_api.MediaListParams
+import uniffi.wp_api.MediaType
 import uniffi.wp_api.SparseMediaFieldWithEditContext
 import uniffi.wp_api.WpAuthenticationProvider
 import java.io.File
 import kotlin.test.assertEquals
 import kotlin.test.assertNotNull
+import kotlin.test.assertTrue
 
 private const val MEDIA_ID_611: Long = 611
 
@@ -32,6 +34,26 @@ class MediaEndpointTest {
         assertNotNull(media)
     }
 
+    @Test
+    fun testMediaTypeWrapperComparison() = runTest {
+        val media = client.request { requestBuilder ->
+            requestBuilder.media().filterRetrieveWithEditContext(
+                mediaId = MEDIA_ID_611,
+                fields = listOf(SparseMediaFieldWithEditContext.MEDIA_TYPE)
+            )
+        }.assertSuccessAndRetrieveData().data
+        val mediaType = assertNotNull(media.mediaType)
+
+        // The wrapper's isMediaType should match the named variant
+        assertTrue(mediaType.isMediaType(MediaType.Image))
+
+        // Crucially: it should also match Custom("image") — this is the forward-compat
+        // guarantee. Code written before `Image` was a named variant used
+        // Custom("image") to check for images. After `Image` gets promoted to a named
+        // variant, that comparison must still work.
+        assertTrue(mediaType.isMediaType(MediaType.Custom("image")))
+    }
+
     @Test
     fun testFilterMediaListRequest() = runTest {
         val mediaList = client.request { requestBuilder ->

wp_api/src/media.rs

@@ -47,6 +47,53 @@ pub enum MediaType {
 
 impl_as_query_value_from_to_string!(MediaType);
 
+#[derive(Debug, Clone, Serialize, Deserialize, uniffi::Object)]
+#[serde(transparent)]
+pub struct MediaTypeWrapper {
+    inner: MediaType,
+}
+
+impl PartialEq for MediaTypeWrapper {
+    fn eq(&self, other: &Self) -> bool {
+        self.inner.to_string() == other.inner.to_string()
+    }
+}
+
+impl Eq for MediaTypeWrapper {}
+
+impl std::fmt::Display for MediaTypeWrapper {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.inner.fmt(f)
+    }
+}
+
+impl std::str::FromStr for MediaTypeWrapper {
+    type Err = <MediaType as std::str::FromStr>::Err;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        MediaType::from_str(s).map(|inner| Self { inner })
+    }
+}
+
+impl MediaTypeWrapper {
+    pub fn inner(&self) -> &MediaType {
+        &self.inner
+    }
+}
+
+impl From<MediaType> for MediaTypeWrapper {
+    fn from(inner: MediaType) -> Self {
+        Self { inner }
+    }
+}
+
+#[uniffi::export]
+impl MediaTypeWrapper {
+    fn is_media_type(&self, media_type: MediaType) -> bool {
+        self.inner.to_string() == media_type.to_string()
+    }
+}
+
 // A separate param type is implemented for `MediaType` because the API will accept types such as
 // "audio" & "application" as a parameter, but it'll return "file" for the value of `media_type`
 // field for these media types.
@@ -409,7 +456,7 @@ pub struct SparseMedia {
     #[WpContextualField]
     pub description: Option<SparseMediaDescription>,
     #[WpContext(edit, embed, view)]
-    pub media_type: Option<MediaType>,
+    pub media_type: Option<Arc<MediaTypeWrapper>>,
     #[WpContext(edit, embed, view)]
     pub mime_type: Option<String>,
     #[WpContext(edit, embed, view)]

wp_mobile/src/filters/media_list_filter.rs

@@ -153,7 +153,7 @@ impl MediaListFilter {
         // Media type check.
         if let Some(param) = &self.media_type {
             let media_mime_top = media.mime_type.split_once('/').map(|(top, _)| top);
-            let matches = match (param, &media.media_type) {
+            let matches = match (param, media.media_type.inner()) {
                 (MediaTypeParam::Image, MediaType::Image) => true,
                 (MediaTypeParam::Image, MediaType::File) => false,
                 (MediaTypeParam::Video, MediaType::File) => media_mime_top == Some("video"),

wp_mobile_cache/src/repository/media.rs

@@ -17,7 +17,8 @@ use rusqlite::{OptionalExtension, Row};
 use std::{collections::HashMap, marker::PhantomData, sync::Arc};
 use wp_api::{
     media::{
-        MediaCaptionWithEditContext, MediaDescriptionWithEditContext, MediaId, MediaWithEditContext,
+        MediaCaptionWithEditContext, MediaDescriptionWithEditContext, MediaId, MediaTypeWrapper,
+        MediaWithEditContext,
     },
     posts::{PostGuidWithEditContext, PostTitleWithEditContext},
     prelude::WpGmtDateTime,
@@ -317,7 +318,7 @@ impl MediaContext for EditContext {
                 raw: row.get_column(DescriptionRaw)?,
                 rendered: row.get_column(DescriptionRendered)?,
             },
-            media_type: parse_enum(row, MediaType)?,
+            media_type: Arc::new(parse_enum::<MediaTypeWrapper, _>(row, MediaType)?),
             mime_type: row.get_column(MimeType)?,
             media_details,
             post_id: get_optional_id(row, PostId)?,

wp_mobile_cache/src/test_fixtures/media.rs

@@ -3,7 +3,7 @@ use std::sync::atomic::{AtomicI64, Ordering};
 use wp_api::{
     media::{
         MediaCaptionWithEditContext, MediaDescriptionWithEditContext, MediaDetails, MediaId,
-        MediaStatus, MediaType, MediaWithEditContext,
+        MediaStatus, MediaType, MediaTypeWrapper, MediaWithEditContext,
     },
     posts::{
         PostCommentStatus, PostGuidWithEditContext, PostId, PostPingStatus,
@@ -104,7 +104,7 @@ impl MediaBuilder {
 
     /// Set the media type.
     pub fn with_media_type(mut self, media_type: MediaType) -> Self {
-        self.media.media_type = media_type;
+        self.media.media_type = Arc::new(MediaTypeWrapper::from(media_type));
         self
     }
 
@@ -161,7 +161,7 @@ fn create_minimal_media() -> MediaWithEditContext {
             raw: String::new(),
             rendered: String::new(),
         },
-        media_type: MediaType::File,
+        media_type: Arc::new(MediaTypeWrapper::from(MediaType::File)),
         mime_type: "application/octet-stream".into(),
         media_details: Arc::new(MediaDetails {
             payload: serde_json::value::RawValue::from_string("{}".into()).unwrap(),
@@ -177,7 +177,7 @@ fn create_full_media() -> MediaWithEditContext {
     m.password = Some("secret".into());
     m.post_id = Some(PostId(100));
     m.alt_text = "alt text".into();
-    m.media_type = MediaType::Image;
+    m.media_type = Arc::new(MediaTypeWrapper::from(MediaType::Image));
     m.mime_type = "image/jpeg".into();
     m.caption = MediaCaptionWithEditContext {
         raw: "caption raw".into(),