[TS/JS] Entry point per namespace and reworked 1.x compatible single file build (#7510)

* [TS/JS] Entry point per namespace

* Fix handling of outputpath and array_test

* Attempt to fix generate_code

* Fix cwd for ts in generate_code

* Attempt to fixup bazel and some docs

* Add --ts-flat-files to bazel build to get bundle

* Move to DEFAULT_FLATC_TS_ARGS

* Attempt to add esbuild

* Attempt to use npm instead

* Remove futile attempt to add esbuild

* Attempt to as bazel esbuild

* Shuffle

* Upgrade bazel deps

* Revert failed attempts to get bazel working

* Ignore flatc tests for now

* Add esbuild dependency

* `package.json` Include esbuild

* `WORKSPACE` Add fetching esbuild binary

* Update WORKSPACE

* Unfreeze Lockfile

* Update WORKSPACE

* Update BUILD.bazel

* Rework to suggest instead of running external bundler

* Add esbuild generation to test script

* Prelim bundle test

* Run test JavaScriptTest from flatbuffers 1.x

* Deps upgrade

* Clang format fix

* Revert bazel changes

* Fix newline

* Generate with type declarations

* Handle "empty" root namespace

* Adjust tests for typescript_keywords.ts

* Separate test procedure for old node resolution module output

* Fix rel path for root level re-exports

* Bazel support for esbuild-based flatc

Unfortunately, we lose typing information because the new esbuild method
of generating single files does not generate type information.

The method used here is a bit hack-ish because it relies on parsing the
console output of flatc to figure out what to do.

* Try to fix bazel build for when node isn't present on host

* Auto formatting fixes

* Fix missing generated code

Co-authored-by: Derek Bailey <derekbailey@google.com>
Co-authored-by: James Kuszmaul <jabukuszmaul+collab@gmail.com>

package.json

@@ -9,8 +9,20 @@
     "mjs/**/*.d.ts",
     "ts/**/*.ts"
   ],
-  "main": "js/index.js",
-  "module": "mjs/index.js",
+  "main": "js/flatbuffers.js",
+  "module": "mjs/flatbuffers.js",
+  "exports": {
+    ".": {
+      "node": {
+        "import": "./mjs/flatbuffers.js",
+        "require": "./js/flatbuffers.js"
+      },
+      "default": "./js/flatbuffers.js"
+    },
+    "./js/flexbuffers.js": {
+      "default": "./js/flexbuffers.js"
+    }
+  },
   "directories": {
     "doc": "docs",
     "test": "tests"
@@ -18,7 +30,7 @@
   "scripts": {
     "test": "npm run compile && cd tests/ts && python3 ./TypeScriptTest.py",
     "lint": "eslint ts",
-    "compile": "tsc && tsc -p tsconfig.mjs.json && rollup -c",
+    "compile": "tsc && tsc -p tsconfig.mjs.json && esbuild js/flatbuffers.js --minify --global-name=flatbuffers --bundle --outfile=js/flatbuffers.min.js",
     "prepublishOnly": "npm install --only=dev && npm run compile"
   },
   "repository": {
@@ -38,10 +50,10 @@
   "devDependencies": {
     "@bazel/typescript": "5.2.0",
     "@types/node": "18.7.16",
-    "@typescript-eslint/eslint-plugin": "^5.36.2",
-    "@typescript-eslint/parser": "^5.36.2",
-    "eslint": "^8.23.1",
-    "rollup": "^2.79.0",
+    "@typescript-eslint/eslint-plugin": "^5.46.0",
+    "@typescript-eslint/parser": "^5.46.0",
+    "esbuild": "^0.16.4",
+    "eslint": "^8.29.0",
     "typescript": "^4.8.3"
   }
 }