Mark AST deserialisation done

docs/behavioural-testing-in-rust-with-cucumber.md

@@ -1135,7 +1135,7 @@ aligned with what is needed.
     Stack Overflow, accessed on 14 July 2025,
     <https://stackoverflow.com/questions/30505639/how-to-do-error-handling-in-rust-and-what-are-the-common-pitfalls>
 
-[^23]: Data tables - Cucumber Rust Book, accessed on 14 July 2025,
+[^23]: Data tables – Cucumber Rust Book — accessed on 14 July 2025 —
     <https://cucumber-rs.github.io/cucumber/main/writing/data_tables.html>
 
 [^24]: Cucumber Data Tables — Tutorialspoint, accessed on 14 July 2025,
@@ -1164,8 +1164,8 @@ aligned with what is needed.
     accessed on July 14, 2025,
     <https://medium.com/@realtalkdev/common-challenges-in-cucumber-testing-and-how-to-overcome-them-dc95fffb43c8>
 
-[^31]: Cucumber in cucumber - Rust - [Docs.rs](http://Docs.rs), accessed on
-    14 July 2025,
+[^31]: Cucumber in cucumber – Rust – [Docs.rs](http://Docs.rs) — accessed on 14
+       July 2025 —
     <https://docs.rs/cucumber/latest/cucumber/struct.Cucumber.html>
 
 [^32]: CLI (command-line interface) - Cucumber Rust Book, accessed on

docs/netsuke-design.md

@@ -493,6 +493,49 @@ pub enum StringOrList {
 flexibility for users to specify single sources, dependencies, and rule names
 as a simple string and multiple as a list, enhancing user-friendliness.*
 
+#### Example Manifest and AST
+
+The following minimal Netsukefile shows how the derived structures behave when
+unknown fields are denied.
+
+YAML
+
+```yaml
+netsuke_version: "1.0.0"
+targets:
+  - name: hello
+    recipe:
+      kind: command
+      command: echo hi
+```
+
+Rust
+
+```rust
+use std::collections::HashMap;
+use netsuke::ast::*;
+
+let ast = NetsukeManifest {
+    netsuke_version: Version::parse("1.0.0").unwrap(),
+    vars: HashMap::new(),
+    rules: vec![],
+    steps: vec![],
+    targets: vec![Target {
+        name: StringOrList::String("hello".into()),
+        recipe: Recipe::Command {
+            command: "echo hi".into(),
+        },
+        sources: StringOrList::Empty,
+        deps: StringOrList::Empty,
+        order_only_deps: StringOrList::Empty,
+        vars: HashMap::new(),
+        phony: false,
+        always: false,
+    }],
+    defaults: vec![],
+};
+```
+
 ### 3.3 The Two-Pass Parsing Requirement
 
 The integration of a templating engine like Jinja fundamentally shapes the
@@ -549,6 +592,14 @@ follows semantic versioning rules. Global and target variable maps now share
 the `HashMap<String, String>` type for consistency. This keeps YAML manifests
 concise while ensuring forward compatibility.
 
+### 3.5 Testing
+
+Unit tests in `tests/ast_tests.rs` and behavioural scenarios in
+`tests/features/manifest.feature` exercise the deserialization logic. They
+assert that manifests fail to parse when unknown fields are present, and that a
+minimal manifest round-trips correctly. This suite guards against regressions
+as the schema evolves.
+
 ## Section 4: Dynamic Builds with the Jinja Templating Engine
 
 To provide the dynamic capabilities and logical expressiveness that make a

docs/roadmap.md

@@ -20,9 +20,9 @@ compilation pipeline from parsing to execution.
     (NetsukeManifest, Rule, Target, StringOrList, Recipe) in `src/ast.rs`.
     *(done)*
 
-  - [ ] Annotate AST structs with #[derive(Deserialize)] and
+  - [x] Annotate AST structs with #[derive(Deserialize)] and
     #[serde(deny_unknown_fields)]
-    to enable serde_yml parsing.
+    to enable serde_yml parsing. *(done)*
 
   - [ ] Implement parsing for the netsuke_version field and validate it using
     the semver crate.

tests/steps/manifest_steps.rs

@@ -7,7 +7,7 @@ use std::fs;
 
 #[expect(
     clippy::needless_pass_by_value,
-    reason = "Cucumber requires owned String arguments",
+    reason = "Cucumber requires owned String arguments"
 )]
 #[when(expr = "the manifest file {string} is parsed")]
 fn parse_manifest(world: &mut CliWorld, path: String) {