test: verify browser WASM config parity

web/workspace/test/config-source/api.test.ts

@@ -0,0 +1,60 @@
+/// <reference lib="deno.ns" />
+
+import { assert, assertEquals } from "jsr:@std/assert";
+import {
+  commitConfigTree,
+  fetchConfigEntry,
+  fetchConfigTree,
+  previewConfigTree,
+} from "../../src/lib/workspace/config-source/api.ts";
+
+function response(body: unknown, status = 200): Response {
+  return new Response(JSON.stringify(body), {
+    status,
+    headers: { "content-type": "application/json" },
+  });
+}
+
+Deno.test("config source API stays workspace-scoped and separates preview from commit", async () => {
+  const calls: Array<{ url: string; init?: RequestInit }> = [];
+  const fetcher = ((input: string | URL | Request, init?: RequestInit) => {
+    calls.push({ url: String(input), init });
+    return Promise.resolve(response({ ok: true }));
+  }) as typeof fetch;
+
+  await fetchConfigTree("w/one", fetcher);
+  await fetchConfigEntry("w/one", "profiles/main.dcdl", fetcher);
+  await previewConfigTree("w/one", { changes: [], entrypoints: [] }, fetcher);
+  await commitConfigTree("w/one", {
+    base_revision: 4,
+    base_digest: "sha256:base",
+    changes: [],
+    entrypoints: [],
+  }, fetcher);
+
+  assertEquals(calls.map((call) => call.url), [
+    "/api/w/w%2Fone/config/source-tree",
+    "/api/w/w%2Fone/config/source-tree/entries/profiles%2Fmain.dcdl",
+    "/api/w/w%2Fone/config/source-tree/preview",
+    "/api/w/w%2Fone/config/source-tree/commit",
+  ]);
+  assertEquals(calls[2].init?.method, "POST");
+  assertEquals(calls[3].init?.method, "POST");
+  assert(
+    String(calls[3].init?.body).includes('"base_digest":"sha256:base"'),
+  );
+});
+
+Deno.test("config source API surfaces failed evaluation instead of treating it as a draft write", async () => {
+  const fetcher = (() =>
+    Promise.resolve(
+      new Response("structured diagnostics", { status: 422 }),
+    )) as typeof fetch;
+  let message = "";
+  try {
+    await previewConfigTree("w", { changes: [], entrypoints: [] }, fetcher);
+  } catch (error) {
+    message = String(error);
+  }
+  assert(message.includes("structured diagnostics"));
+});

web/workspace/test/config-source/wasm-parity.test.ts

@@ -0,0 +1,67 @@
+/// <reference lib="deno.ns" />
+
+import { assertEquals } from "jsr:@std/assert";
+// The generated wasm-bindgen loader is JavaScript with an adjacent declaration file.
+// @ts-expect-error Deno checks the generated JS implementation rather than its .d.ts.
+import init, {
+  analyze_snapshot,
+  evaluate_snapshot,
+} from "../../src/lib/workspace/config-source/generated/config_source_wasm.js";
+import type { ConfigTreeSnapshot, ToolchainContract } from "../../src/lib/workspace/config-source/types.ts";
+
+const bytes = await Deno.readFile(
+  new URL("../../src/lib/workspace/config-source/generated/config_source_wasm_bg.wasm", import.meta.url),
+);
+await init({ module_or_path: bytes });
+
+const snapshot: ConfigTreeSnapshot = {
+  revision: 4,
+  digest: "sha256:test-tree",
+  entries: {
+    "workspace.dcdl": {
+      path: "workspace.dcdl",
+      content_type: "decodal",
+      content: 'import "./lib/value.dcdl"',
+      content_digest: "sha256:root",
+    },
+    "lib/value.dcdl": {
+      path: "lib/value.dcdl",
+      content_type: "decodal",
+      content: "{ answer = 42; }",
+      content_digest: "sha256:value",
+    },
+  },
+};
+
+const contract: ToolchainContract = {
+  contract_version: 1,
+  decodal_version: "0.2.0",
+  schema_version: 1,
+  entrypoints: ["workspace.dcdl"],
+  import_policy_version: 1,
+  fingerprint: "sha256:test-contract",
+};
+
+Deno.test("generated WASM evaluates the same virtual import contract", () => {
+  const result = evaluate_snapshot(snapshot, contract) as {
+    projections: Array<{ data_json: { answer: number } }>;
+  };
+  assertEquals(result.projections[0].data_json, { answer: 42 });
+});
+
+Deno.test("generated WASM diagnostics carry snapshot provenance", () => {
+  const diagnostics = analyze_snapshot(
+    snapshot,
+    "workspace.dcdl",
+    "{ broken = ; }",
+  ) as Array<{
+    path: string;
+    revision: number;
+    tree_digest: string;
+    kind: string;
+  }>;
+  assertEquals(diagnostics[0].path, "workspace.dcdl");
+  assertEquals(diagnostics[0].revision, 4);
+  assertEquals(diagnostics[0].tree_digest, "sha256:test-tree");
+  assertEquals(diagnostics[0].kind, "syntax");
+});