test: generate the external module fixture instead of copying ignored build output

The test proving that migrations of a module installed outside the repository
are discovered, while Core's come from the platform, copied templates/module
including dist/. dist/ is gitignored and never committed. CI runs `pnpm test`
before any build of the template, where only the template's own UI test may
have written dist/ui, dist/display, and dist/contributions, so discovery
failed with MODULE_ENTRYPOINT_MISSING for ./dist/server/index.js and
./dist/schema/index.js (and, had the UI test not run yet, the copy itself
would have failed). Locally a previous `pnpm build` had left dist/ complete.

The test now generates a minimal valid installed module in a temporary
directory with createMigrationModule, moved unchanged from the migration
discovery test into core/tests/support so both share it. It depends on no
build output, ignored file, or node_modules. It also asserts more precisely:
the module directory is outside the repository, Core's migrations match the
platform's own core/drizzle inventory by identity and checksum, and the
module's migration matches the SQL that was installed.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

core/tests/module-migration-discovery.test.ts

@@ -1,5 +1,5 @@
 import { createHash } from "node:crypto";
-import { mkdir, mkdtemp, rm, symlink, writeFile } from "node:fs/promises";
+import { mkdtemp, rm, symlink, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import path from "node:path";
 import { afterEach, describe, expect, it } from "vitest";
@@ -10,34 +10,15 @@ import {
   ModuleMigrationDiscoveryError,
   type ModuleMigrationDiscoveryIssueCode,
 } from "../src/modules/index.js";
+import {
+  createMigrationModule,
+  manifestFor,
+  originSnapshotId,
+  snapshotId,
+} from "./support/migration-module-fixture.js";
 
-const originSnapshotId = "00000000-0000-0000-0000-000000000000";
 const temporaryDirectories: string[] = [];
 
-interface MigrationFixture {
-  readonly breakpoints?: boolean;
-  readonly destructive?:
-    | { readonly mode: "none" }
-    | { readonly mode: "approval-required"; readonly reason: string };
-  readonly snapshotId?: string;
-  readonly sql: string | Uint8Array;
-  readonly tag: string;
-  readonly timestamp?: number;
-}
-
-interface MigrationModuleFixture {
-  readonly dependencies?: Record<string, unknown>;
-  readonly manifest?: Record<string, unknown>;
-  readonly migrations?: readonly MigrationFixture[] | false;
-  readonly schemaSource?: string;
-  readonly serverSource?: string;
-}
-
-interface CreatedMigrationModule {
-  readonly migrationDirectory?: string;
-  readonly moduleDirectory: string;
-}
-
 afterEach(async () => {
   await Promise.all(
     temporaryDirectories
@@ -52,139 +33,6 @@ async function createModulesDirectory(): Promise<string> {
   return directory;
 }
 
-function snapshotId(index: number): string {
-  return `10000000-0000-4000-8000-${(index + 1).toString(16).padStart(12, "0")}`;
-}
-
-function manifestFor(
-  id: string,
-  options: {
-    readonly dependencies?: Record<string, unknown>;
-    readonly migrations?: boolean;
-    readonly schema?: boolean;
-  } = {},
-): Record<string, unknown> {
-  return {
-    manifestVersion: 7,
-    id,
-    name: `${id} module`,
-    version: "0.1.0",
-    compatibility: { platform: "^0.1.0", moduleSdk: "^0.1.0" },
-    ...(options.dependencies ? { dependencies: options.dependencies } : {}),
-    capabilities: [],
-    permissions: [],
-    entrypoints: {
-      server: "./dist/server/index.js",
-      ...(options.schema ? { schema: "./dist/schema/index.js" } : {}),
-      ...(options.migrations === false ? {} : { migrations: "./drizzle" }),
-    },
-  };
-}
-
-function defaultMigrations(id: string): readonly MigrationFixture[] {
-  return [
-    {
-      sql: `CREATE TABLE "${id.replaceAll("-", "_")}_records" ("id" integer);\n`,
-      tag: "0000_initial",
-    },
-  ];
-}
-
-async function createMigrationModule(
-  modulesDirectory: string,
-  id: string,
-  fixture: MigrationModuleFixture = {},
-): Promise<CreatedMigrationModule> {
-  const migrations =
-    fixture.migrations === false ? undefined : (fixture.migrations ?? defaultMigrations(id));
-  const moduleDirectory = path.join(modulesDirectory, id);
-  const migrationDirectory = migrations ? path.join(moduleDirectory, "drizzle") : undefined;
-  await mkdir(path.join(moduleDirectory, "dist/server"), { recursive: true });
-  if (fixture.schemaSource !== undefined) {
-    await mkdir(path.join(moduleDirectory, "dist/schema"), { recursive: true });
-  }
-  if (migrationDirectory) {
-    await mkdir(path.join(migrationDirectory, "meta"), { recursive: true });
-  }
-
-  await Promise.all([
-    writeFile(
-      path.join(moduleDirectory, "package.json"),
-      JSON.stringify({
-        name: `@test/module-${id}`,
-        version: "0.1.0",
-        type: "module",
-        ekklesia: { layer: "module" },
-      }),
-    ),
-    writeFile(
-      path.join(moduleDirectory, "ekklesia.module.json"),
-      JSON.stringify(
-        fixture.manifest ??
-          manifestFor(id, {
-            ...(fixture.dependencies ? { dependencies: fixture.dependencies } : {}),
-            migrations: migrations !== undefined,
-            schema: fixture.schemaSource !== undefined,
-          }),
-      ),
-    ),
-    writeFile(
-      path.join(moduleDirectory, "dist/server/index.js"),
-      fixture.serverSource ?? `export default { id: ${JSON.stringify(id)}, version: "0.1.0" };`,
-    ),
-    ...(fixture.schemaSource === undefined
-      ? []
-      : [writeFile(path.join(moduleDirectory, "dist/schema/index.js"), fixture.schemaSource)]),
-  ]);
-
-  if (!migrationDirectory || !migrations) {
-    return { moduleDirectory };
-  }
-
-  const journalEntries = migrations.map((migration, index) => ({
-    idx: index,
-    version: "7",
-    when: migration.timestamp ?? 1_700_000_000_000 + index,
-    tag: migration.tag,
-    breakpoints: migration.breakpoints ?? true,
-  }));
-  const policyEntries = migrations.map((migration) => ({
-    tag: migration.tag,
-    destructive: migration.destructive ?? { mode: "none" },
-  }));
-  await Promise.all([
-    writeFile(
-      path.join(migrationDirectory, "meta/_journal.json"),
-      JSON.stringify({ version: "7", dialect: "postgresql", entries: journalEntries }),
-    ),
-    writeFile(
-      path.join(migrationDirectory, "meta/_ekklesia.json"),
-      JSON.stringify({ version: 1, moduleId: id, entries: policyEntries }),
-    ),
-    ...migrations.flatMap((migration, index) => {
-      const idForSnapshot = migration.snapshotId ?? snapshotId(index);
-      const previousId =
-        index === 0
-          ? originSnapshotId
-          : (migrations[index - 1]?.snapshotId ?? snapshotId(index - 1));
-      return [
-        writeFile(path.join(migrationDirectory, `${migration.tag}.sql`), migration.sql),
-        writeFile(
-          path.join(migrationDirectory, `meta/${index.toString().padStart(4, "0")}_snapshot.json`),
-          JSON.stringify({
-            version: "7",
-            dialect: "postgresql",
-            id: idForSnapshot,
-            prevId: previousId,
-          }),
-        ),
-      ];
-    }),
-  ]);
-
-  return { migrationDirectory, moduleDirectory };
-}
-
 function discoveryOptions(modulesDirectory: string) {
   return {
     moduleSdkVersion: "0.1.0",