Implement main-thread Camino sessions and synchronous CRDT editing

src/bindings/client.ts

@@ -11,6 +11,8 @@ export const generateClientContracts = (
     throw new Error("Host contracts require closed interface applications, not generic definitions");
   const type = (value: ValueType): string => {
     switch (value.kind) {
+      case "variant":
+        throw new Error("Variants require the Camino portable value runtime; legacy RPC bindings are unsupported");
       case "builtin":
         return value.name === "unit" ? "undefined" : "string";
       case "scalar":

src/bindings/generics.ts

@@ -49,6 +49,8 @@ export const genericImplementationType = (
   const value = (type: ValueTypeExpression, scope: Scope, depth = 0): string => {
     if (depth > 128) throw new Error("Generic type expansion exceeds depth limit");
     switch (type.kind) {
+      case "variant":
+        throw new Error("Variants require the Camino portable value runtime; legacy RPC bindings are unsupported");
       case "parameter": {
         const bound = scope.arguments.get(type.parameterId);
         if (bound) return bound;

src/bindings/index.ts

@@ -112,6 +112,8 @@ export const generateTypeScriptBindings = (
   const messages = new Map<string, string>();
   const type = (value: ValueType): string => {
     switch (value.kind) {
+      case "variant":
+        throw new Error("Variants require the Camino portable value runtime; legacy RPC bindings are unsupported");
       case "builtin":
         return value.name === "unit" ? "null" : "QxWatchHandle";
       case "scalar":
@@ -340,6 +342,7 @@ export const generateTypeScriptBindings = (
   // A used port still fails above if its own required codec is missing.
   const hasCodec = (value: ValueType): boolean => {
     if (value.kind === "message") return !!options.messages?.[value.descriptorId];
+    if (value.kind === "variant") return false;
     if (value.kind === "record") return Object.values(value.fields).every(hasCodec);
     if (value.kind === "list" || value.kind === "optional") return hasCodec(value.value);
     return true;

src/bindings/portable.ts

@@ -29,6 +29,17 @@ const expectation = (e: ObjectExpectation) => ({
 /** The protocol IR and replica wire schema intentionally share structure, not reference identity. */
 export function portableValueSchema(type: ValueType): unknown {
   switch (type.kind) {
+    case "variant":
+      return {
+        kind: "variant",
+        id: type.id,
+        cases: Object.fromEntries(
+          Object.entries(type.cases).map(([label, entry]) => [
+            label,
+            { id: entry.id, value: portableValueSchema(entry.value) },
+          ]),
+        ),
+      };
     case "change":
       return {
         kind: "record",
@@ -65,6 +76,10 @@ export function portableValueSchema(type: ValueType): unknown {
 export function tsType(type: ValueType): string {
   portableValueSchema(type);
   switch (type.kind) {
+    case "variant":
+      return `(${Object.entries(type.cases)
+        .map(([label, entry]) => `{ readonly kind: ${q(label)}; readonly value: ${tsType(entry.value)} }`)
+        .join(" | ")})`;
     case "change":
       return `PreparedChange<${tsType(type.value)}>`;
     case "scalar":

src/bindings/react.ts

@@ -15,6 +15,8 @@ export function generateReactBindings(
   const declarations: string[] = [];
   const type = (value: ValueType): string => {
     switch (value.kind) {
+      case "variant":
+        throw new Error("Variants require the Camino portable value runtime; legacy RPC bindings are unsupported");
       case "builtin":
         if (value.name !== "unit") throw new Error(`Unsupported React props builtin ${value.name}`);
         return "null";
@@ -85,6 +87,7 @@ export function generateReactBindings(
   const browserValue = (value: ValueType, seen: Set<string>): boolean => {
     if (value.kind === "message") return false;
     if (value.kind === "builtin") return value.name === "unit";
+    if (value.kind === "variant") return false;
     if (value.kind === "record") return Object.values(value.fields).every((field) => browserValue(field, seen));
     if (value.kind === "list" || value.kind === "optional") return browserValue(value.value, seen);
     if (value.kind === "object-ref" && value.expectation.kind === "interface") {