Files
mizan/cores/mizan-rust/tests/merge_resolution.rs
Ryth Azhur 3aafec6dd4 A channel's message slots are named from the client, on every backend
The IR called them react-message and django-message, so a FastAPI channel had
to declare a DjangoMessage. They are client-message and server-message now,
and the direction words hold wherever a channel is declared: Params /
ClientMessage / ServerMessage, with mizan-core deriving <Pascal>Params and
friends so no backend names a type itself. Django's ReactChannel and
FastAPI's ReactChannel are both Channel.

mizan-fastapi never registered a channels extension, so build_ir() emitted no
channel at all and every payload type was invisible to codegen. It registers
one now. RegistryExtension is an ABC requiring all(), which is what the IR
reads — an extension that cannot enumerate its registrations no longer exists.

The gate that should have caught the rename could not: tests/afi registered no
channel because mizan-rust had no channel registry to register one in, so a
five-package rename of the wire contract passed byte-parity without a channel
byte crossing it. mizan-rust grows ChannelSlotKind, a CHANNELS slice, a
#[mizan::channel] macro, and KDL emission whose wire_to_pascal matches Python's
split; the AFI fixture now carries a channel with every slot and one with a
single slot, so all three backends prove the contract byte for byte.

MizanChannel held three Option<String> beside three has_*() predicates and
unwrapped them with defaults; it holds an ordered slot vector, so an absent
slot is absent rather than defaulted. The channels target emitted a React
hooks file that a stage1-only consumer could not compile — react emits that
now. The codegen's parity tests byte-compared emitted source against baselines
without ever compiling it: they compile the generated crate and run its tests,
import the generated Python package and call every method, and typecheck each
TypeScript target against a consumer.

Also fixed at source: app_visitor printed its import diagnostic to stdout, the
stream export_mizan_ir writes KDL to, so a failed import silently corrupted the
IR; the apps root was hardcoded to "apps"; _default_literal crashed build_ir on
any non-JSON-serializable field default; Django and mizan-core derived Pascal
names two different ways, disagreeing on every dotted channel name.

ir.py builds a document and renders templates/ir/document.kdl.j2 rather than
appending KDL strings with hand-tracked indentation, and named types resolve to
a fixed point — a model reachable only through a union branch was referenced by
a ref that no type block ever defined.

The rest is the write-gate's own classifiers run over the standing tree:
relative imports, silent swallows, Protocol contracts that should be ABCs,
emitters hand-rendering target source, catch-all arms over closed enums, and
comments narrating the project rather than the code.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-27 14:03:19 -04:00

114 lines
3.4 KiB
Rust

//! `compute_merges` over a graph registered through `#[derive(Mizan)]`,
//! `#[mizan::context]` and `#[mizan::client]`.
use mizan_core as mizan;
use mizan_core::prelude::*;
use mizan_core::{compute_merges, RequestHandle, FUNCTIONS};
use serde::{Deserialize, Serialize};
#[derive(Mizan, Serialize, Deserialize, Debug, Clone)]
pub struct ProfileOutput {
pub user_id: i64,
pub name: String,
}
#[derive(Mizan, Serialize, Deserialize, Debug, Clone)]
pub struct StatusOutput {
pub ok: bool,
}
#[mizan::context("user")]
pub struct UserCtx;
#[mizan::client(context = UserCtx)]
pub async fn user_profile(_req: &RequestHandle<'_>, user_id: i64) -> ProfileOutput {
ProfileOutput {
user_id,
name: format!("user-{user_id}"),
}
}
#[mizan::client(merge = UserCtx)]
pub async fn rename_user(
_req: &RequestHandle<'_>,
user_id: i64,
name: String,
) -> ProfileOutput {
ProfileOutput { user_id, name }
}
#[mizan::client(affects = UserCtx)]
pub async fn touch_user(_req: &RequestHandle<'_>, user_id: i64) -> StatusOutput {
StatusOutput { ok: user_id > 0 }
}
/// The handlers above register into `FUNCTIONS` inside this test binary, so a
/// name they declare always lands.
fn spec(name: &str) -> &'static dyn FunctionSpec {
for fn_spec in FUNCTIONS.iter().copied() {
if fn_spec.name() == name {
return fn_spec;
}
}
panic!("no registered function named `{name}`");
}
/// `user_id` is a declared param of the `user` context; `name` is not.
fn args() -> serde_json::Map<String, serde_json::Value> {
let mut args = serde_json::Map::new();
args.insert("user_id".to_string(), serde_json::Value::from(7));
args.insert("name".to_string(), serde_json::Value::from("Renamed"));
args
}
fn renamed() -> serde_json::Value {
serde_json::json!({ "user_id": 7, "name": "Renamed" })
}
#[test]
fn a_merge_declaration_resolves_to_the_context_member_sharing_its_output() {
let result = renamed();
let merges = compute_merges(spec("rename_user"), &args(), &result);
let [entry] = merges.as_slice() else {
panic!(
"rename_user declares one merge; got {} entries",
merges.len()
);
};
assert_eq!(entry.context, "user");
assert_eq!(entry.slot, "user_profile");
assert_eq!(entry.value, result);
}
#[test]
fn a_merge_entry_is_scoped_by_the_contexts_declared_params_alone() {
let result = renamed();
let merges = compute_merges(spec("rename_user"), &args(), &result);
let [entry] = merges.as_slice() else {
panic!(
"rename_user declares one merge; got {} entries",
merges.len()
);
};
let mut expected = serde_json::Map::new();
expected.insert("user_id".to_string(), serde_json::Value::from(7));
assert_eq!(entry.params, Some(expected));
}
#[test]
fn a_function_declaring_only_affects_produces_no_merge_entries() {
let result = serde_json::json!({ "ok": true });
assert!(compute_merges(spec("touch_user"), &args(), &result).is_empty());
}
#[test]
fn merge_resolution_answers_identically_across_calls() {
let result = renamed();
let first = compute_merges(spec("rename_user"), &args(), &result);
let second = compute_merges(spec("rename_user"), &args(), &result);
let slots: Vec<&str> = first.iter().map(|e| e.slot.as_str()).collect();
let again: Vec<&str> = second.iter().map(|e| e.slot.as_str()).collect();
assert_eq!(slots, again);
assert_eq!(slots, vec!["user_profile"]);
}