fix: Fix .apply serialization error with optional structs (#886)

<!--
Pull requests are squashed and merged using:
- their title as the commit message
- their description as the commit body

Having a good title and description is important for the users to get
readable changelog.
-->

<!-- 1. Explain WHAT the change is about -->

- Fix the error on `.apply` when the apply tree goes beyond an optional
struct, mostly changing the implementation of `resolve_optional` method.
- Improve the errors when we encounter an exception raise by
`Result::Err` from typegraph_core.

<!-- 2. Explain WHY the change cannot be made simpler -->



<!-- 3. Explain HOW users should update their code -->

#### Migration notes

...

- [x] The change comes with new or modified tests
- [ ] Hard-to-understand functions have explanatory comments
- [ ] End-user documentation is updated to reflect the change

src/typegraph/core/src/global_store.rs

@@ -6,7 +6,9 @@ use crate::runtimes::{
     DenoMaterializer, Materializer, MaterializerData, MaterializerDenoModule, Runtime,
 };
 use crate::types::type_ref::TypeRef;
-use crate::types::{NamedTypeRef, Type, TypeDef, TypeDefExt, TypeId, TypeRefBuilder};
+use crate::types::{
+    AsTypeDefEx as _, NamedTypeRef, Type, TypeDef, TypeDefExt, TypeId, TypeRefBuilder,
+};
 use crate::wit::core::{Policy as CorePolicy, PolicyId, RuntimeId};
 use crate::wit::utils::Auth as WitAuth;
 
@@ -489,22 +491,22 @@ impl TypeId {
     as_variant!(List);
 
     pub fn is_func(&self) -> Result<bool> {
-        Ok(matches!(self.as_type_def()?, Some(TypeDef::Func(_))))
+        Ok(matches!(self.as_xdef()?.type_def, TypeDef::Func(_)))
     }
 
     pub fn resolve_quant(&self) -> Result<TypeId> {
         let type_id = *self;
-        match type_id.as_type_def()? {
-            Some(TypeDef::List(a)) => Ok(a.data.of.into()),
-            Some(TypeDef::Optional(o)) => Ok(o.data.of.into()),
+        match type_id.as_xdef()?.type_def {
+            TypeDef::List(a) => Ok(a.data.of.into()),
+            TypeDef::Optional(o) => Ok(o.data.of.into()),
             _ => Ok(type_id),
         }
     }
 
     pub fn resolve_optional(&self) -> Result<TypeId> {
         let type_id = *self;
-        match type_id.as_type_def()? {
-            Some(TypeDef::Optional(o)) => Ok(o.data.of.into()),
+        match type_id.as_xdef()?.type_def {
+            TypeDef::Optional(o) => Ok(o.data.of.into()),
             _ => Ok(type_id),
         }
     }

src/typegraph/core/src/params/apply.rs

@@ -150,7 +150,9 @@ pub fn build_transform_data(
     root_fields: &HashMap<String, raw_tree::ParameterTransformNode>,
 ) -> Result<TransformData> {
     let mut context = TransformDataBuildContext::default();
-    let (new_tree, type_id) = context.check_object_node(resolver_input, root_fields)?;
+    let (new_tree, type_id) = context
+        .check_object_node(resolver_input, root_fields)
+        .context("building apply transform tree")?;
 
     let mut query_input_type = t::struct_();
     for (name, param) in context.query_params.into_iter() {

src/typegraph/core/src/runtimes/prisma/type_generation/filters.rs

@@ -148,7 +148,7 @@ pub(super) struct ScalarListFilter(pub TypeId);
 
 impl TypeGen for ScalarListFilter {
     fn generate(&self, _context: &PrismaContext) -> Result<TypeId> {
-        if let Some(TypeDef::Optional(_)) = self.0.as_type_def()? {
+        if let TypeDef::Optional(_) = self.0.as_xdef()?.type_def {
             return Err("array of optional not supported".into());
         }
 
@@ -251,7 +251,7 @@ impl TypeGen for AvgFilter {
             .filter_map(|(k, type_id)| {
                 let type_def = type_id.as_xdef().unwrap().type_def;
                 let non_opt_type = match type_def {
-                    TypeDef::Optional(inner) => inner.item().as_type_def().unwrap().unwrap(),
+                    TypeDef::Optional(inner) => inner.item().as_xdef().unwrap().type_def,
                     _ => type_def,
                 };
                 match non_opt_type {

src/typegraph/core/src/runtimes/prisma/type_generation/snapshots/typegraph_core__runtimes__prisma__type_generation__test__find_many Post inp.snap

@@ -21,23 +21,23 @@ root: struct 'Post_query_input' #306
 │        │        ├─ [id]: optional '_prisma_sort' #79
 │        │        │  └─ item: union #76
 │        │        │     ├─ variant_0: struct #75
-│        │        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        │        └─ [name]: optional '_prisma_sort' #79
 │        │           └─ item: union #76
 │        │              ├─ variant_0: struct #75
-│        │              │  └─ [sort]: string '_prisma_sort_order' #72
-│        │              └─ variant_1: string '_prisma_sort_order' #72
+│        │              │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │              └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        ├─ [id]: optional '_prisma_sort' #79
 │        │  └─ item: union #76
 │        │     ├─ variant_0: struct #75
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        └─ [title]: optional '_prisma_sort' #79
 │           └─ item: union #76
 │              ├─ variant_0: struct #75
-│              │  └─ [sort]: string '_prisma_sort_order' #72
-│              └─ variant_1: string '_prisma_sort_order' #72
+│              │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 ├─ [skip]: optional 'optional_291' #292
 │  └─ item: integer '_skip' #96
 ├─ [take]: optional 'optional_289' #290

src/typegraph/core/src/runtimes/prisma/type_generation/snapshots/typegraph_core__runtimes__prisma__type_generation__test__find_many Record inp.snap

@@ -22,24 +22,24 @@ root: struct 'Record_query_input' #114
 │        ├─ [age]: optional '_prisma_sort_nullable' #84
 │        │  └─ item: union #81
 │        │     ├─ variant_0: struct #80
-│        │     │  ├─ [nulls]: string '_prisma_nulls_order' #74
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  ├─ [nulls]: string '_prisma_nulls_order' #74 enum{ '"first"', '"last"' }
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        ├─ [created_at]: optional '_prisma_sort' #79
 │        │  └─ item: union #76
 │        │     ├─ variant_0: struct #75
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        ├─ [id]: optional '_prisma_sort' #79
 │        │  └─ item: union #76
 │        │     ├─ variant_0: struct #75
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        └─ [name]: optional '_prisma_sort' #79
 │           └─ item: union #76
 │              ├─ variant_0: struct #75
-│              │  └─ [sort]: string '_prisma_sort_order' #72
-│              └─ variant_1: string '_prisma_sort_order' #72
+│              │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 ├─ [skip]: optional 'optional_97' #98
 │  └─ item: integer '_skip' #96
 ├─ [take]: optional 'optional_93' #94

src/typegraph/core/src/runtimes/prisma/type_generation/snapshots/typegraph_core__runtimes__prisma__type_generation__test__find_many User inp.snap

@@ -18,40 +18,40 @@ root: struct 'User_query_input' #217
 │        ├─ [id]: optional '_prisma_sort' #79
 │        │  └─ item: union #76
 │        │     ├─ variant_0: struct #75
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        ├─ [name]: optional '_prisma_sort' #79
 │        │  └─ item: union #76
 │        │     ├─ variant_0: struct #75
-│        │     │  └─ [sort]: string '_prisma_sort_order' #72
-│        │     └─ variant_1: string '_prisma_sort_order' #72
+│        │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│        │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │        └─ [posts]: optional '_prisma_sort_by_aggregates' #193
 │           └─ item: struct #190
 │              ├─ [_avg]: optional '_prisma_sort' #79
 │              │  └─ item: union #76
 │              │     ├─ variant_0: struct #75
-│              │     │  └─ [sort]: string '_prisma_sort_order' #72
-│              │     └─ variant_1: string '_prisma_sort_order' #72
+│              │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │              ├─ [_count]: optional '_prisma_sort' #79
 │              │  └─ item: union #76
 │              │     ├─ variant_0: struct #75
-│              │     │  └─ [sort]: string '_prisma_sort_order' #72
-│              │     └─ variant_1: string '_prisma_sort_order' #72
+│              │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │              ├─ [_max]: optional '_prisma_sort' #79
 │              │  └─ item: union #76
 │              │     ├─ variant_0: struct #75
-│              │     │  └─ [sort]: string '_prisma_sort_order' #72
-│              │     └─ variant_1: string '_prisma_sort_order' #72
+│              │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │              ├─ [_min]: optional '_prisma_sort' #79
 │              │  └─ item: union #76
 │              │     ├─ variant_0: struct #75
-│              │     │  └─ [sort]: string '_prisma_sort_order' #72
-│              │     └─ variant_1: string '_prisma_sort_order' #72
+│              │     │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│              │     └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 │              └─ [_sum]: optional '_prisma_sort' #79
 │                 └─ item: union #76
 │                    ├─ variant_0: struct #75
-│                    │  └─ [sort]: string '_prisma_sort_order' #72
-│                    └─ variant_1: string '_prisma_sort_order' #72
+│                    │  └─ [sort]: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
+│                    └─ variant_1: string '_prisma_sort_order' #72 enum{ '"asc"', '"desc"' }
 ├─ [skip]: optional 'optional_202' #203
 │  └─ item: integer '_skip' #96
 ├─ [take]: optional 'optional_200' #201