Merge TS loader unification (Phase 3)

Retires FileMetaDataLoader; introduces MetaDataLoader.fromDirectory/fromUris/
fromString factories + module-level loadDirectory/loadUris/loadString shortcuts.
Polymorphic Source impls: FileSource/DirectorySource/UriSource/InMemoryStringSource.
Browser-safety preserved via dynamic imports of yaml + node:fs paths.

2533 tests passing (+20 net from loader-unification tests).
Pre-existing integration-test failures (Docker required) are unchanged.

Author: dmealing

server/typescript/packages/cli/test/unit/payload-field-tree.test.ts

@@ -1,10 +1,10 @@
 import { describe, test, expect } from "bun:test";
-import { MetaDataLoader, InMemorySource } from "@metaobjectsdev/metadata";
+import { MetaDataLoader, InMemoryStringSource } from "@metaobjectsdev/metadata";
 import { derivePayloadFieldTree } from "../../src/lib/payload-field-tree.js";
 
 async function loadRoot(children: unknown[]) {
   const res = await new MetaDataLoader().load([
-    new InMemorySource(JSON.stringify({ "metadata.root": { package: "acme::ai", children } })),
+    new InMemoryStringSource(JSON.stringify({ "metadata.root": { package: "acme::ai", children } })),
   ]);
   expect(res.errors).toEqual([]);
   return res.root;

server/typescript/packages/cli/test/unit/projection-migrations.test.ts

@@ -1,13 +1,13 @@
 import { describe, test, expect } from "bun:test";
-import { MetaDataLoader, InMemorySource } from "@metaobjectsdev/metadata";
+import { MetaDataLoader, InMemoryStringSource } from "@metaobjectsdev/metadata";
 import { computeProjectionMigrations } from "../../src/lib/projection-migrations.js";
 
 // ---------------------------------------------------------------------------
 // Helper — wrap children in metadata envelope and load.
 // ---------------------------------------------------------------------------
 async function load(children: unknown[]) {
   const json = JSON.stringify({ "metadata.root": { package: "test", children } });
-  const result = await new MetaDataLoader().load([new InMemorySource(json)]);
+  const result = await new MetaDataLoader().load([new InMemoryStringSource(json)]);
   if (result.errors.length > 0) {
     throw new Error(
       `Loader errors:\n${result.errors.map((e) => e.message).join("\n")}`,

server/typescript/packages/codegen-ts-react/test/cross-target.test.ts

@@ -1,8 +1,9 @@
 import { describe, it, expect } from "bun:test";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { resolve } from "node:path";
 import { makeRenderContext, buildPkMap, buildRelationMap, type ResolvedTarget } from "@metaobjectsdev/codegen-ts";
 import { renderFormFile } from "../src/templates/form-file.js";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 // Product lives in package "shop::commerce" → package-layout path "shop/commerce/Product".
 const FIXTURE = resolve(import.meta.dir, "fixtures", "packaged-entity.json");
@@ -11,7 +12,7 @@ const model: ResolvedTarget = { name: "default", outDir: "db/gen", importBase: "
 const web:   ResolvedTarget = { name: "web", outDir: "web/gen", importBase: undefined, outputLayout: "package", dbImport: "../index" };
 
 async function ctxFor(self: ResolvedTarget, em: ResolvedTarget) {
-  const { root } = await new FileMetaDataLoader().loadFiles([FIXTURE]);
+  const { root } = await new MetaDataLoader().load([new FileSource(FIXTURE)]);
   const entity = root.objects().find((o) => o.name === "Product")!;
   const ctx = makeRenderContext({
     dialect: "sqlite", loadedRoot: root, outDir: self.outDir, dbImport: self.dbImport,

server/typescript/packages/codegen-ts-tanstack/test/cross-target.test.ts

@@ -1,9 +1,10 @@
 import { describe, it, expect } from "bun:test";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { resolve } from "node:path";
 import { makeRenderContext, buildPkMap, buildRelationMap, type ResolvedTarget } from "@metaobjectsdev/codegen-ts";
 import { renderHooksFile } from "../src/templates/hooks-file.js";
 import { renderColumnsFile } from "../src/templates/columns-file.js";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 // Product lives in package "shop::commerce" → package-layout path "shop/commerce/Product".
 const FIXTURE = resolve(import.meta.dir, "fixtures", "packaged-grid-entity.json");
@@ -12,7 +13,7 @@ const model: ResolvedTarget = { name: "default", outDir: "db/gen", importBase: "
 const web:   ResolvedTarget = { name: "web", outDir: "web/gen", importBase: undefined, outputLayout: "package", dbImport: "../index" };
 
 async function ctxFor(self: ResolvedTarget, em: ResolvedTarget) {
-  const { root } = await new FileMetaDataLoader().loadFiles([FIXTURE]);
+  const { root } = await new MetaDataLoader().load([new FileSource(FIXTURE)]);
   const entity = root.objects().find((o) => o.name === "Product")!;
   const ctx = makeRenderContext({
     dialect: "sqlite", loadedRoot: root, outDir: self.outDir, dbImport: self.dbImport,

server/typescript/packages/codegen-ts-tanstack/test/golden/grid-hook-golden.test.ts

@@ -20,10 +20,11 @@ import {
 } from "node:fs";
 import { tmpdir } from "node:os";
 import { join, resolve } from "node:path";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { runGen, defineConfig } from "@metaobjectsdev/codegen-ts";
 import { entityFile } from "@metaobjectsdev/codegen-ts/generators";
 import { tanstackGridHook } from "../../src/index.js";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 const SNAP = join(import.meta.dir, "__snapshots__");
 const UPDATE = process.env.UPDATE_GOLDEN === "1";
@@ -55,7 +56,7 @@ const fixtures = [
 describe("tanstackGridHook() — golden snapshot", () => {
   for (const fixture of fixtures) {
     it(`generates byte-identical .grid.ts output — ${fixture.name}`, async () => {
-      const { root, errors } = await new FileMetaDataLoader().loadFiles([fixture.path]);
+      const { root, errors } = await new MetaDataLoader().load([new FileSource(fixture.path)]);
       if (errors.length > 0) {
         throw new Error(`Fixture load errors: ${errors.join(", ")}`);
       }

server/typescript/packages/codegen-ts-tanstack/test/integration.test.ts

@@ -2,10 +2,11 @@ import { describe, test, expect, beforeEach, afterEach } from "bun:test";
 import { mkdtempSync, rmSync, readdirSync, readFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join, resolve } from "node:path";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { runGen, defineConfig } from "@metaobjectsdev/codegen-ts";
 import { entityFile, queriesFile, routesFile, barrel } from "@metaobjectsdev/codegen-ts/generators";
 import { tanstackQuery, tanstackGrid } from "../src/index.js";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 const MULTI_GRID = resolve(import.meta.dir, "fixtures", "multi-grid-entity.json");
 
@@ -15,7 +16,7 @@ afterEach(() => { rmSync(tmp, { recursive: true, force: true }); });
 
 describe("Full pipeline — Project A + Project B generators together", () => {
   test("emits Program.ts, Program.queries.ts, Program.routes.ts, Program.hooks.ts, Program.columns.tsx, index.ts", async () => {
-    const { root } = await new FileMetaDataLoader().loadFiles([MULTI_GRID]);
+    const { root } = await new MetaDataLoader().load([new FileSource(MULTI_GRID)]);
     const out = await runGen({
       config: defineConfig({
         outDir: tmp, extStyle: "none", dbImport: "../db", dialect: "sqlite",
@@ -51,7 +52,7 @@ describe("Full pipeline — Project A + Project B generators together", () => {
   });
 
   test("all generators emit their expected file kinds together (happy path)", async () => {
-    const { root } = await new FileMetaDataLoader().loadFiles([MULTI_GRID]);
+    const { root } = await new MetaDataLoader().load([new FileSource(MULTI_GRID)]);
     const out = await runGen({
       config: defineConfig({
         outDir: tmp, extStyle: "none", dbImport: "../db", dialect: "sqlite",

server/typescript/packages/codegen-ts-tanstack/test/package-layout.test.ts

@@ -2,10 +2,11 @@ import { describe, test, expect, beforeEach, afterEach } from "bun:test";
 import { mkdtempSync, rmSync, readdirSync, readFileSync, existsSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join, resolve } from "node:path";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { runGen, defineConfig } from "@metaobjectsdev/codegen-ts";
 import { entityFile } from "@metaobjectsdev/codegen-ts/generators";
 import { tanstackQuery, tanstackGrid } from "../src/index.js";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 const PACKAGED_GRID = resolve(import.meta.dir, "fixtures", "packaged-grid-entity.json");
 
@@ -15,7 +16,7 @@ afterEach(() => { rmSync(tmp, { recursive: true, force: true }); });
 
 describe("package-aware output placement — tanstackQuery + tanstackGrid", () => {
   test("package layout: hooks and columns land in package sub-path alongside entity file", async () => {
-    const { root, errors } = await new FileMetaDataLoader().loadFiles([PACKAGED_GRID]);
+    const { root, errors } = await new MetaDataLoader().load([new FileSource(PACKAGED_GRID)]);
     expect(errors).toEqual([]);
 
     const out = await runGen({
@@ -57,7 +58,7 @@ describe("package-aware output placement — tanstackQuery + tanstackGrid", () =
   });
 
   test("flat layout (default): hooks and columns land at outDir root", async () => {
-    const { root, errors } = await new FileMetaDataLoader().loadFiles([PACKAGED_GRID]);
+    const { root, errors } = await new MetaDataLoader().load([new FileSource(PACKAGED_GRID)]);
     expect(errors).toEqual([]);
 
     const out = await runGen({
@@ -80,7 +81,7 @@ describe("package-aware output placement — tanstackQuery + tanstackGrid", () =
   });
 
   test("extStyle: js — hooks and columns import the entity with a .js extension", async () => {
-    const { root, errors } = await new FileMetaDataLoader().loadFiles([PACKAGED_GRID]);
+    const { root, errors } = await new MetaDataLoader().load([new FileSource(PACKAGED_GRID)]);
     expect(errors).toEqual([]);
 
     const out = await runGen({

server/typescript/packages/codegen-ts-tanstack/test/projection-hooks.test.ts

@@ -4,7 +4,7 @@
 //   - vanilla entities still emit all 5 hooks (read + create/update/delete)
 
 import { describe, test, expect } from "bun:test";
-import { MetaDataLoader, InMemorySource } from "@metaobjectsdev/metadata";
+import { MetaDataLoader, InMemoryStringSource } from "@metaobjectsdev/metadata";
 import { renderHooksFile } from "../src/templates/hooks-file.js";
 import { makeRenderContext, buildPkMap, buildRelationMap } from "@metaobjectsdev/codegen-ts";
 
@@ -14,7 +14,7 @@ import { makeRenderContext, buildPkMap, buildRelationMap } from "@metaobjectsdev
 
 async function loadMetadata(children: unknown[]) {
   const json = JSON.stringify({ "metadata.root": { package: "test", children } });
-  const result = await new MetaDataLoader().load([new InMemorySource(json)]);
+  const result = await new MetaDataLoader().load([new InMemoryStringSource(json)]);
   if (result.errors.length > 0) {
     throw new Error(
       `Loader errors:\n${result.errors.map((e: { message: string }) => e.message).join("\n")}`,

server/typescript/packages/codegen-ts-tanstack/test/tanstack-grid.test.ts

@@ -1,16 +1,17 @@
 import { describe, test, expect } from "bun:test";
 import { resolve } from "node:path";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { tanstackGrid } from "../src/tanstack-grid.js";
 import { makeRenderContext, buildPkMap, buildRelationMap } from "@metaobjectsdev/codegen-ts";
 import type { GenContext } from "@metaobjectsdev/codegen-ts";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 const FIXTURE        = resolve(import.meta.dir, "fixtures", "single-entity.json");
 const MULTI_GRID     = resolve(import.meta.dir, "fixtures", "multi-grid-entity.json");
 const GRID_FILTER    = resolve(import.meta.dir, "fixtures", "grid-filter-fixture.json");
 
 async function ctxFor(fixturePath: string): Promise<GenContext> {
-  const { root } = await new FileMetaDataLoader().loadFiles([fixturePath]);
+  const { root } = await new MetaDataLoader().load([new FileSource(fixturePath)]);
   const entities = root.objects();
   const renderContext = makeRenderContext({
     dialect: "sqlite", loadedRoot: root, outDir: "/tmp",

server/typescript/packages/codegen-ts-tanstack/test/tanstack-query-filter.test.ts

@@ -1,16 +1,17 @@
 import { describe, test, expect } from "bun:test";
 import { resolve } from "node:path";
-import { FileMetaDataLoader } from "@metaobjectsdev/metadata/core";
 import { tanstackQuery } from "../src/tanstack-query.js";
 import { makeRenderContext } from "@metaobjectsdev/codegen-ts";
 import { buildPkMap, buildRelationMap } from "@metaobjectsdev/codegen-ts";
 import type { GenContext } from "@metaobjectsdev/codegen-ts";
+import { MetaDataLoader } from "@metaobjectsdev/metadata";
+import { FileSource } from "@metaobjectsdev/metadata/core";
 
 const FIXTURE = resolve(import.meta.dir, "..", "..", "codegen-ts", "test", "fixtures", "filter-fixture.json");
 
 async function buildCtx(): Promise<GenContext> {
-  const loader = new FileMetaDataLoader();
-  const { root } = await loader.loadFiles([FIXTURE]);
+  const loader = new MetaDataLoader();
+  const { root } = await loader.load([new FileSource(FIXTURE)]);
   const entities = root.objects();
   const renderContext = makeRenderContext({
     dialect: "sqlite",