Jest (#3145)

This changes to use Jest. Benefits of jest is parallel tests and jest can run the minimal set of tests that are affected by a change (by looking at dependencies).

The main work was to disentangle our cyclic dependencies. To do this I had to remove some runtime assertions in encode value as well as expose the values of a struct without going through a struct mirror.

js/noms/.gitignore

@@ -3,3 +3,4 @@ dist
 generated-docs
 .nyc_output
 coverage.lcov
+coverage

js/noms/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@attic/noms",
   "license": "Apache-2.0",
-  "version": "69.6.0",
+  "version": "69.6.1",
   "description": "Noms JS SDK",
   "repository": "https://github.com/attic-labs/noms/tree/master/js/noms",
   "main": "dist/commonjs/noms.js",
@@ -27,6 +27,7 @@
     "flow-bin": "^0.38.0",
     "flow-copy-source": "^1.1.0",
     "fs-extra": "^2.0.0",
+    "jest": "^18.1.0",
     "mocha": "^3.2.0",
     "mock-require": "^2.0.1",
     "nyc": "^10.1.2"
@@ -34,10 +35,8 @@
   "scripts": {
     "lint": "eslint src/",
     "flow": "flow src/",
-    "pretest": "yarn run lint && yarn run flow",
-    "ts": "mocha --ui tdd --timeout=4000 --reporter dot --slow=50 --invert --grep='LONG:' --compilers js:babel-core/register src/*-test.js",
-    "test-no-cov": "mocha --ui tdd --timeout=30000 --reporter dot --compilers js:babel-core/register src/*-test.js",
-    "test": "nyc yarn run test-no-cov && nyc report --reporter=text-lcov > coverage.lcov",
+    "jest": "jest",
+    "test": "yarn run lint && yarn run flow && jest --coverage",
     "prepublish": "rm -rf dist/ && yarn run compile && yarn run flow-copy-source",
     "compile": "yarn run compile-to-commonjs",
     "compile-to-commonjs": "BABEL_ENV=production babel -d dist/commonjs src/ > /dev/null",
@@ -52,5 +51,11 @@
     "./dist/commonjs/fetch.js": "./dist/commonjs/browser/fetch.js",
     "./src/put-cache.js": "./src/browser/put-cache.js",
     "./dist/commonjs/put-cache.js": "./dist/commonjs/browser/put-cache.js"
+  },
+  "jest": {
+    "testRegex": ".+-test\\.js$",
+    "testPathIgnorePatterns": [
+      "/dist/"
+    ]
   }
 }

js/noms/src/absolute-path-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {equals} from './compare.js';
 
 import {invariant, notNull} from './assert.js';

js/noms/src/assert-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import {invariant, notNull} from './assert.js';
 

js/noms/src/assert-type-test.js

@@ -10,7 +10,7 @@ import List from './list.js';
 import Map from './map.js';
 import Set from './set.js';
 import {newStruct} from './struct.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import assertSubtype, {isSubtype} from './assert-type.js';
 import type {Type} from './type.js';
 import {

js/noms/src/base32-test.js

@@ -7,7 +7,7 @@
 import {encode, decode} from './base32.js';
 import {assert} from 'chai';
 import {alloc} from './bytes.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 suite('base32', () => {
   test('encode', () => {

js/noms/src/binary-noms-reader.js

@@ -0,0 +1,33 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import * as Bytes from './bytes.js';
+import Hash, {byteLength as hashByteLength} from './hash.js';
+import type TypeCache from './type-cache.js';
+import {BinaryReader} from './binary-rw.js';
+
+export default class BinaryNomsReader extends BinaryReader {
+  constructor(buff: Uint8Array) {
+    super(buff);
+  }
+
+  readIdent(tc: TypeCache): number {
+    const str = this.readString(); // TODO: Figure out how to do this without allocating.
+    let id = tc.identTable.entries.get(str);
+    if (id === undefined) {
+      id = tc.identTable.getId(str);
+    }
+
+    return id;
+  }
+
+  readHash(): Hash {
+    // Make a copy of the data.
+    const digest = Bytes.slice(this.buff, this.offset, this.offset + hashByteLength);
+    this.offset += hashByteLength;
+    return new Hash(digest);
+  }
+}

js/noms/src/binary-noms-writer.js

@@ -0,0 +1,45 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import * as Bytes from './bytes.js';
+import Hash, {byteLength as hashByteLength} from './hash.js';
+import ValueEncoder from './value-encoder.js';
+import type {Type} from './type.js';
+import {notNull} from './assert.js';
+import {BinaryWriter} from './binary-rw.js';
+
+function ensureTypeSerialization(t: Type<any>) {
+  if (!t.serialization) {
+    const w = new BinaryNomsWriter();
+    const enc = new ValueEncoder(w, null);
+    enc.writeType(t, []);
+    t.serialization = w.data;
+  }
+}
+
+export default class BinaryNomsWriter extends BinaryWriter {
+  constructor() {
+    super();
+  }
+
+  writeHash(h: Hash): void {
+    this.ensureCapacity(hashByteLength);
+    Bytes.copy(h.digest, this.buff, this.offset);
+    this.offset += hashByteLength;
+  }
+
+  appendType(t: Type<any>): void {
+    // Note: The JS & Go impls differ here. The Go impl eagerly serializes types as they are
+    // constructed. The JS does it lazily so as to avoid cyclic package dependencies.
+    ensureTypeSerialization(t);
+    const data = notNull(t.serialization);
+    const size = data.byteLength;
+    this.ensureCapacity(size);
+
+    Bytes.copy(data, this.buff, this.offset);
+    this.offset += size;
+  }
+}

js/noms/src/blob-test.js

@@ -7,7 +7,7 @@
 import {blobType, makeRefType} from './type.js';
 import {assert} from 'chai';
 import Blob, {BlobReader, BlobWriter} from './blob.js';
-import {suite, suiteSetup, suiteTeardown, test, setup, teardown} from 'mocha';
+import {suite, suiteSetup, suiteTeardown, test, setup, teardown} from './jest.js';
 import {
   assertChunkCountAndType,
   assertValueHash,

js/noms/src/buzhash-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import BuzHash from './buzhash.js';
 import * as Bytes from './bytes.js';

js/noms/src/bytes-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 import * as NodeBytes from './bytes.js';
 import * as BrowserBytes from './browser/bytes.js';

js/noms/src/chunk-serializer-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import Chunk from './chunk.js';
 import type Hash from './hash.js';

js/noms/src/chunk-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import Chunk from './chunk.js';
 import Hash from './hash.js';

js/noms/src/codec.js

@@ -1,130 +0,0 @@
-// Copyright 2016 Attic Labs, Inc. All rights reserved.
-// Licensed under the Apache License, version 2.0:
-// http://www.apache.org/licenses/LICENSE-2.0
-
-// @flow
-
-import * as Bytes from './bytes.js';
-import Chunk from './chunk.js';
-import Hash, {byteLength as hashByteLength} from './hash.js';
-import ValueDecoder from './value-decoder.js';
-import ValueEncoder from './value-encoder.js';
-import type Value from './value.js';
-import type {Type} from './type.js';
-import type {ValueReader, ValueWriter} from './value-store.js';
-import {default as TypeCache, staticTypeCache} from './type-cache.js';
-import {notNull} from './assert.js';
-import {setEncodeValue} from './get-hash.js';
-import {setHash, ValueBase} from './value.js';
-import {BinaryReader, BinaryWriter} from './binary-rw.js';
-
-export function encodeValue(v: Value, vw: ?ValueWriter): Chunk {
-  const w = new BinaryNomsWriter();
-  const enc = new ValueEncoder(w, vw);
-  enc.writeValue(v);
-  const chunk = new Chunk(w.data);
-  if (v instanceof ValueBase) {
-    setHash(v, chunk.hash);
-  }
-
-  return chunk;
-}
-
-setEncodeValue(encodeValue);
-
-export function decodeValue(chunk: Chunk, vr: ValueReader): Value {
-  const data = chunk.data;
-  const br = new BinaryNomsReader(data);
-  const dec = new ValueDecoder(br, vr, staticTypeCache);
-  const v = dec.readValue();
-  if (br.pos() !== data.byteLength) {
-    throw new Error('Invalid chunk data: not all bytes consumed');
-  }
-  if (v instanceof ValueBase) {
-    setHash(v, chunk.hash);
-  }
-
-  return v;
-}
-
-function ensureTypeSerialization(t: Type<any>) {
-  if (!t.serialization) {
-    const w = new BinaryNomsWriter();
-    const enc = new ValueEncoder(w, null);
-    enc.writeType(t, []);
-    t.serialization = w.data;
-  }
-}
-
-export interface NomsReader {
-  pos(): number;
-  seek(pos: number): void;
-  readBytes(): Uint8Array;
-  readUint8(): number;
-  readUint32(): number;
-  readUint64(): number;
-  readNumber(): number;
-  readBool(): boolean;
-  readString(): string;
-  readIdent(tc: TypeCache): number;
-  readHash(): Hash;
-}
-
-export interface NomsWriter {
-  writeBytes(v: Uint8Array): void;
-  writeUint8(v: number): void;
-  writeUint32(v: number): void;
-  writeUint64(v: number): void;
-  writeNumber(v: number): void;
-  writeBool(v: boolean): void;
-  writeString(v: string): void;
-  writeHash(h: Hash): void;
-  appendType(t: Type<any>): void;
-}
-
-export class BinaryNomsReader extends BinaryReader {
-  constructor(buff: Uint8Array) {
-    super(buff);
-  }
-
-  readIdent(tc: TypeCache): number {
-    const str = this.readString(); // TODO: Figure out how to do this without allocating.
-    let id = tc.identTable.entries.get(str);
-    if (id === undefined) {
-      id = tc.identTable.getId(str);
-    }
-
-    return id;
-  }
-
-  readHash(): Hash {
-    // Make a copy of the data.
-    const digest = Bytes.slice(this.buff, this.offset, this.offset + hashByteLength);
-    this.offset += hashByteLength;
-    return new Hash(digest);
-  }
-}
-
-export class BinaryNomsWriter extends BinaryWriter {
-  constructor() {
-    super();
-  }
-
-  writeHash(h: Hash): void {
-    this.ensureCapacity(hashByteLength);
-    Bytes.copy(h.digest, this.buff, this.offset);
-    this.offset += hashByteLength;
-  }
-
-  appendType(t: Type<any>): void {
-    // Note: The JS & Go impls differ here. The Go impl eagerly serializes types as they are
-    // constructed. The JS does it lazily so as to avoid cyclic package dependencies.
-    ensureTypeSerialization(t);
-    const data = notNull(t.serialization);
-    const size = data.byteLength;
-    this.ensureCapacity(size);
-
-    Bytes.copy(data, this.buff, this.offset);
-    this.offset += size;
-  }
-}

js/noms/src/commit-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import {equals} from './compare.js';
 import {

js/noms/src/compare-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import {equals, compare} from './compare.js';
 import {

js/noms/src/database-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import makeRemoteBatchStoreFake from './remote-batch-store-fake.js';
 import {TestingDelegate} from './remote-batch-store-fake.js';
 import RemoteBatchStore from './remote-batch-store.js';
@@ -15,7 +15,7 @@ import Database from './database.js';
 import {notNull} from './assert.js';
 import List from './list.js';
 import Struct, {newStruct} from './struct.js';
-import {encodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
 import NomsSet from './set.js'; // namespace collision with JS Set
 import {invariant} from './assert.js';
 import {Kind} from './noms-kind.js';

js/noms/src/dataset-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import makeRemoteBatchStoreFake from './remote-batch-store-fake.js';
 import {assert} from 'chai';
 import Database from './database.js';

js/noms/src/decode-value.js

@@ -0,0 +1,28 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import type Chunk from './chunk.js';
+import ValueDecoder from './value-decoder.js';
+import type Value from './value.js';
+import type {ValueReader} from './value-store.js';
+import {staticTypeCache} from './type-cache.js';
+import {setHash, ValueBase} from './value.js';
+import BinaryNomsReader from './binary-noms-reader.js';
+
+export default function decodeValue(chunk: Chunk, vr: ValueReader): Value {
+  const data = chunk.data;
+  const br = new BinaryNomsReader(data);
+  const dec = new ValueDecoder(br, vr, staticTypeCache);
+  const v = dec.readValue();
+  if (br.pos() !== data.byteLength) {
+    throw new Error('Invalid chunk data: not all bytes consumed');
+  }
+  if (v instanceof ValueBase) {
+    setHash(v, chunk.hash);
+  }
+
+  return v;
+}

js/noms/src/edit-distance-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import type {Splice} from './edit-distance.js';
 import {assert} from 'chai';
 import {DEFAULT_MAX_SPLICE_MATRIX_SIZE, calcSplices} from './edit-distance.js';

js/noms/src/encode-human-readable-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 import {invariant, notNull} from './assert.js';
 import {TypeWriter} from './encode-human-readable.js';

js/noms/src/encode-value.js

@@ -0,0 +1,24 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import Chunk from './chunk.js';
+import ValueEncoder from './value-encoder.js';
+import type Value from './value.js';
+import type {ValueWriter} from './value-store.js';
+import {setHash, ValueBase} from './value.js';
+import BinaryNomsWriter from './binary-noms-writer.js';
+
+export default function encodeValue(v: Value, vw: ?ValueWriter): Chunk {
+  const w = new BinaryNomsWriter();
+  const enc = new ValueEncoder(w, vw);
+  enc.writeValue(v);
+  const chunk = new Chunk(w.data);
+  if (v instanceof ValueBase) {
+    setHash(v, chunk.hash);
+  }
+
+  return chunk;
+}

js/noms/src/encoding-test.js

@@ -5,7 +5,7 @@
 /* eslint-disable max-len */
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 
 import Blob from './blob.js';
@@ -22,7 +22,8 @@ import type Value from './value.js';
 import {ValueBase} from './value.js';
 import {Kind} from './noms-kind.js';
 import {TestDatabase} from './test-util.js';
-import {encodeValue, decodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
+import decodeValue from './decode-value.js';
 import {equals} from './compare.js';
 import {invariant, notNull} from './assert.js';
 import {newStruct, newStructWithType} from './struct.js';

js/noms/src/fetch-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test, setup, teardown} from 'mocha';
+import {suite, test, setup, teardown} from './jest.js';
 import mock from 'mock-require';
 
 suite('fetch', () => {

js/noms/src/get-hash-test.js

@@ -7,7 +7,7 @@
 import Hash from './hash.js';
 import {assert} from 'chai';
 import {ensureHash} from './get-hash.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 suite('get hash', () => {
   test('ensureHash', () => {

js/noms/src/get-hash.js

@@ -4,16 +4,12 @@
 
 // @flow
 
-import type Chunk from './chunk.js';
 import type Hash from './hash.js';
-import type {ValueWriter} from './value-store.js';
 import {notNull} from './assert.js';
 import type Value from './value.js';
 import {getTypeOfValue} from './type.js';
 import {ValueBase} from './value.js';
-
-type encodeFn = (v: Value, vw: ?ValueWriter) => Chunk;
-let encodeValue: ?encodeFn = null;
+import encodeValue from './encode-value.js';
 
 /**
  * Returns the hash of a Noms value. All Noms values have a unique hash and if two values have the
@@ -38,7 +34,3 @@ export function ensureHash(h: ?Hash, v: Value): Hash {
 
   return getHash(v);
 }
-
-export function setEncodeValue(encode: encodeFn) {
-  encodeValue = encode;
-}

js/noms/src/hash-test.js

@@ -8,7 +8,7 @@ import Hash, {emptyHash} from './hash.js';
 import {assert} from 'chai';
 import * as Bytes from './bytes.js';
 import {notNull} from './assert.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 suite('Hash', () => {
   test('parse', () => {

js/noms/src/http-batch-store-test.js

@@ -4,16 +4,17 @@
 
 // @flow
 
-import {suite, test, setup, teardown} from 'mocha';
+import jest, {suite, test, setup, teardown} from './jest.js';
 import {assert} from 'chai';
 import Hash from './hash.js';
 import {emptyHash} from './hash.js';
 import HttpBatchStore from './http-batch-store.js';
-import mock from 'mock-require';
+import {invariant} from './assert.js';
+
 
 suite('HttpBatchStore', () => {
   setup(() => {
-    mock('http', {
+    jest.mock('http', () => ({
       request(options, cb) {
         cb({statusCode: 409});
         return {
@@ -22,11 +23,11 @@ suite('HttpBatchStore', () => {
           setTimeout() {},
         };
       },
-    });
+    }));
   });
 
   teardown(() => {
-    mock.stopAll();
+    jest.resetModules();
   });
 
   test('endpoints', async () => {
@@ -58,11 +59,11 @@ suite('HttpBatchStore', () => {
   });
 
   test('updateRoot conflict', async () => {
-    mock.reRequire('./fetch.js');
-    const HttpBatchStore = mock.reRequire('./http-batch-store.js').default;
+    const HttpBatchStore = require('./http-batch-store.js').default;
     const store = new HttpBatchStore('http://nowhere.com');
 
-    assert.isFalse(
-      await store.updateRoot(Hash.parse('00001111000011110000111100001111'), emptyHash));
+    const h = Hash.parse('00001111000011110000111100001111');
+    invariant(h);
+    assert.isFalse(await store.updateRoot(h, emptyHash));
   });
 });

js/noms/src/http-error-test.js

@@ -6,7 +6,7 @@
 
 import HttpError from './http-error.js';
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 suite('http-error', () => {
   test('prototype', () => {

js/noms/src/indexed-sequence.js

@@ -17,6 +17,8 @@ export async function newCursorAtIndex(sequence: Sequence<any>, idx: number,
   while (sequence) {
     cursor = new IndexedSequenceCursor(cursor, sequence, 0, readAhead);
     idx -= cursor.advanceToOffset(idx);
+    // TODO: The Sequence type needs to be cleaned up.
+    // $FlowIssue: xxx
     sequence = await cursor.getChildSequence();
   }
 

js/noms/src/jest.js

@@ -0,0 +1,24 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+// Tell flow about these. When running the tests these are globals.
+declare var afterAll;
+declare var afterEach;
+declare var beforeAll;
+declare var beforeEach;
+declare var describe;
+declare var it;
+declare var jest;
+
+export {
+  afterAll as suiteTeardown,
+  afterEach as teardown,
+  beforeAll as suiteSetup,
+  beforeEach as setup,
+  describe as suite,
+  it as test,
+  jest as default,
+};

js/noms/src/json-convert-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 
 import jsonToNoms from './json-convert.js';

js/noms/src/list-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, setup, teardown, test} from 'mocha';
+import {suite, setup, teardown, test} from './jest.js';
 
 import List, {ListWriter, ListLeafSequence, newListLeafSequence} from './list.js';
 import Ref from './ref.js';

js/noms/src/map-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, setup, teardown, test} from 'mocha';
+import {suite, setup, teardown, test} from './jest.js';
 
 import Blob from './blob.js';
 import Ref from './ref.js';

js/noms/src/memory-store-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import Chunk from './chunk.js';
 import MemoryStore from './memory-store.js';
 import Hash from './hash.js';

js/noms/src/meta-sequence-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 
 import List from './list.js';
 import {OrderedKey} from './sequence.js';

js/noms/src/noms-reader.js

@@ -0,0 +1,22 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import type Hash from './hash.js';
+import type TypeCache from './type-cache.js';
+
+export interface NomsReader {
+  pos(): number;
+  seek(pos: number): void;
+  readBytes(): Uint8Array;
+  readUint8(): number;
+  readUint32(): number;
+  readUint64(): number;
+  readNumber(): number;
+  readBool(): boolean;
+  readString(): string;
+  readIdent(tc: TypeCache): number;
+  readHash(): Hash;
+}

js/noms/src/noms-writer.js

@@ -0,0 +1,20 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// @flow
+
+import type Hash from './hash.js';
+import type {Type} from './type.js';
+
+export interface NomsWriter {
+  writeBytes(v: Uint8Array): void;
+  writeUint8(v: number): void;
+  writeUint32(v: number): void;
+  writeUint64(v: number): void;
+  writeNumber(v: number): void;
+  writeBool(v: boolean): void;
+  writeString(v: string): void;
+  writeHash(h: Hash): void;
+  appendType(t: Type<any>): void;
+}

js/noms/src/noms.js

@@ -11,7 +11,7 @@ export {default as Commit} from './commit.js';
 export {default as Database} from './database.js';
 export {default as Dataset} from './dataset.js';
 export {default as Blob, BlobReader, BlobWriter} from './blob.js';
-export {decodeValue} from './codec.js';
+export {default as decodeValue} from './decode-value.js';
 export {default as Chunk} from './chunk.js';
 export {getHashOfValue} from './get-hash.js';
 export {BatchStoreAdaptor} from './batch-store.js';
@@ -30,7 +30,7 @@ export {
   createStructClass,
   escapeStructField,
 } from './struct.js';
-export {encodeValue} from './codec.js';
+export {default as encodeValue} from './encode-value.js';
 export {invariant, notNull} from './assert.js';
 export {isPrimitiveKind, Kind, kindToString} from './noms-kind.js';
 export {default as List, ListWriter, ListLeafSequence} from './list.js';

js/noms/src/ordered-sequence-diff-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, suiteSetup, suiteTeardown, test} from 'mocha';
+import {suite, suiteSetup, suiteTeardown, test} from './jest.js';
 import {assert} from 'chai';
 import {OrderedKey} from './sequence.js';
 import {MetaTuple, newSetMetaSequence} from './meta-sequence.js';

js/noms/src/path-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {equals} from './compare.js';
 
 import {getHash} from './get-hash.js';

js/noms/src/put-cache-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import {notNull} from './assert.js';
 import NodeOrderedPutCache from './put-cache.js';

js/noms/src/remote-batch-store-test.js

@@ -4,10 +4,10 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import makeRemoteBatchStoreFake from './remote-batch-store-fake.js';
-import {encodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
 
 suite('BatchStore', () => {
   test('get after schedulePut works immediately', async () => {

js/noms/src/sequence-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import Sequence, {SequenceCursor} from './sequence.js';
 import {notNull} from './assert.js';

js/noms/src/set-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, setup, teardown, test} from 'mocha';
+import {suite, setup, teardown, test} from './jest.js';
 
 import Ref from './ref.js';
 import Set, {SetLeafSequence} from './set.js';

js/noms/src/signed-varint-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {encodingLength, encode, decode, maxVarintLength} from './signed-varint.js';
 import {alloc} from './bytes.js';
 

js/noms/src/spec-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {invariant} from './assert.js';
 import {getHash} from './get-hash.js';
 import List from './list.js';

js/noms/src/specs-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {invariant} from './assert.js';
 import {getHash} from './get-hash.js';
 import List from './list.js';

js/noms/src/struct-test.js

@@ -22,7 +22,7 @@ import {
   numberType,
   stringType,
 } from './type.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {equals} from './compare.js';
 import List from './list.js';
 import Map from './map.js';

js/noms/src/struct.js

@@ -85,6 +85,16 @@ export default class Struct extends ValueBase {
     mirror.forEachField(add);
     return chunks;
   }
+
+  /**
+   * Gets the values of the struct in the same order as the fields. To get the field names you can
+   * inspect the type or use a StructMirror.
+   */
+  get values(): Value[] {
+    // This is exposed this way to allow us breaking cyclic dependencies.
+    // TODO: Use Symbol and expose symbol internally instead?
+    return this._values;
+  }
 }
 
 function validate(type: Type<any>, values: Value[]): void {

js/noms/src/type-cache-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {Kind} from './noms-kind.js';
 import {equals} from './compare.js';
 import {

js/noms/src/type-test.js

@@ -20,9 +20,10 @@ import {
   getTypeOfValue,
 } from './type.js';
 import type {Type} from './type.js';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {equals} from './compare.js';
-import {encodeValue, decodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
+import decodeValue from './decode-value.js';
 import {notNull} from './assert.js';
 
 suite('Type', () => {

js/noms/src/value-decoder.js

@@ -24,7 +24,7 @@ import Set, {SetLeafSequence} from './set.js';
 import {MetaSequence} from './meta-sequence.js';
 import type Value from './value.js';
 import type {ValueReader} from './value-store.js';
-import type {NomsReader} from './codec.js';
+import type {NomsReader} from './noms-reader.js';
 import type TypeCache from './type-cache.js';
 
 export default class ValueDecoder {

js/noms/src/value-encoder.js

@@ -4,21 +4,22 @@
 
 // @flow
 
-import Blob, {BlobLeafSequence} from './blob.js';
-import List, {ListLeafSequence} from './list.js';
-import Map, {MapLeafSequence} from './map.js';
-import Ref, {constructRef} from './ref.js';
+import type {BlobLeafSequence} from './blob.js';
+import type {ListLeafSequence} from './list.js';
+import type {MapLeafSequence} from './map.js';
+import type Ref from './ref.js';
+import {constructRef} from './ref.js';
 import Sequence from './sequence.js';
-import Set, {SetLeafSequence} from './set.js';
-import Struct, {StructMirror} from './struct.js';
+import type {SetLeafSequence} from './set.js';
+import type Struct from './struct.js';
 import type Value from './value.js';
 import type {NomsKind} from './noms-kind.js';
-import type {NomsWriter} from './codec.js';
+import type {NomsWriter} from './noms-writer.js';
 import type {ValueWriter} from './value-store.js';
 import type {primitive} from './primitives.js';
-import {MetaTuple} from './meta-sequence.js';
-import {boolType, CycleDesc, getTypeOfValue, makeRefType, StructDesc, Type} from './type.js';
-import {describeTypeOfValue} from './encode-human-readable.js';
+import type {MetaTuple} from './meta-sequence.js';
+import {boolType, CycleDesc, getTypeOfValue, makeRefType, StructDesc} from './type.js';
+import type {Type} from './type.js';
 import {invariant, notNull} from './assert.js';
 import {isPrimitiveKind, kindToString, Kind} from './noms-kind.js';
 
@@ -111,7 +112,7 @@ export default class ValueEncoder {
     this._w.writeUint32(count);
     for (let i = 0; i < count; i++) {
       const tuple: MetaTuple<any> = v.items[i];
-      invariant(tuple instanceof MetaTuple);
+      // invariant(tuple instanceof MetaTuple);
       const child = tuple.child;
       if (child && this._vw) {
         this._vw.writeValue(child);
@@ -135,85 +136,75 @@ export default class ValueEncoder {
     this._w.appendType(t);
     switch (t.kind) {
       case Kind.Blob: {
-        invariant(v instanceof Blob,
-                  () => `Failed to write Blob. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Blob here.
         const sequence = v.sequence;
         if (this.maybeWriteMetaSequence(sequence)) {
           break;
         }
 
-        invariant(sequence instanceof BlobLeafSequence);
         this.writeBlobLeafSequence(sequence);
         break;
       }
-      case Kind.Bool:
-        invariant(typeof v === 'boolean',
-                  () => `Failed to write Bool. Invalid type: ${describeTypeOfValue(v)}`);
-        this._w.writeBool(v);
+      case Kind.Bool: {
+        // $FlowIssue: We know b is a boolean here.
+        const b: boolean = v;
+        this._w.writeBool(b);
         break;
-      case Kind.Number:
-        invariant(typeof v === 'number',
-                  () => `Failed to write Number. Invalid type: ${describeTypeOfValue(v)}`);
-        if (!Number.isFinite(v)) {
-          throw new Error(`${v} is not a supported number`);
+      }
+      case Kind.Number: {
+        // $FlowIssue: We know n is a number here.
+        const n: number = v;
+        if (!Number.isFinite(n)) {
+          throw new Error(`${n} is not a supported number`);
         }
-        this._w.writeNumber(v);
+        this._w.writeNumber(n);
         break;
+      }
       case Kind.List: {
-        invariant(v instanceof List,
-                  () => `Failed to write List. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a List here.
         const sequence = v.sequence;
         if (this.maybeWriteMetaSequence(sequence)) {
           break;
         }
 
-        invariant(sequence instanceof ListLeafSequence);
         this.writeListLeafSequence(sequence);
         break;
       }
       case Kind.Map: {
-        invariant(v instanceof Map,
-                  () => `Failed to write Map. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Map here.
         const sequence = v.sequence;
         if (this.maybeWriteMetaSequence(sequence)) {
           break;
         }
 
-        invariant(sequence instanceof MapLeafSequence);
         this.writeMapLeafSequence(sequence);
         break;
       }
       case Kind.Ref:
-        invariant(v instanceof Ref,
-                  () => `Failed to write Ref. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Ref here.
         this.writeRef(v);
         break;
       case Kind.Set: {
-        invariant(v instanceof Set,
-                  () => `Failed to write Set. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Set here.
         const sequence = v.sequence;
         if (this.maybeWriteMetaSequence(sequence)) {
           break;
         }
 
-        invariant(sequence instanceof SetLeafSequence);
         this.writeSetLeafSequence(sequence);
         break;
       }
       case Kind.String:
-        invariant(typeof v === 'string',
-                  () => `Failed to write String. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a string here.
         this._w.writeString(v);
         break;
 
       case Kind.Type:
-        invariant(v instanceof Type,
-                  () => `Failed to write Type. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Type here.
         this.writeType(v, []);
         break;
       case Kind.Struct:
-        invariant(v instanceof Struct,
-                  () => `Failed to write Struct. Invalid type: ${describeTypeOfValue(v)}`);
+        // $FlowIssue: We know v is a Struct here.
         this.writeStruct(v);
         break;
       case Kind.Cycle:
@@ -226,10 +217,10 @@ export default class ValueEncoder {
   }
 
   writeStruct(s: Struct) {
-    const mirror = new StructMirror(s);
-    mirror.forEachField(field => {
-      this.writeValue(field.value);
-    });
+    const {values} = s;
+    for (let i = 0; i < values.length; i++) {
+      this.writeValue(values[i]);
+    }
   }
 
   writeCycle(i: number) {

js/noms/src/value-store-test.js

@@ -4,13 +4,13 @@
 
 // @flow
 
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import {assert} from 'chai';
 import MemoryStore from './memory-store.js';
 import {BatchStoreAdaptor} from './batch-store.js';
 import ValueStore from './value-store.js';
 import List from './list.js';
-import {encodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
 import {equals} from './compare.js';
 import Hash from './hash.js';
 import {getHash} from './get-hash.js';

js/noms/src/value-store.js

@@ -18,9 +18,9 @@ import {
 } from './type.js';
 import {Kind} from './noms-kind.js';
 import {ValueBase} from './value.js';
-import {decodeValue} from './codec.js';
+import decodeValue from './decode-value.js';
 import {invariant, notNull} from './assert.js';
-import {encodeValue} from './codec.js';
+import encodeValue from './encode-value.js';
 import {describeType, describeTypeOfValue} from './encode-human-readable.js';
 import {equals} from './compare.js';
 

js/noms/src/walk-test.js

@@ -4,7 +4,7 @@
 
 // @flow
 
-import {suite, suiteSetup, suiteTeardown, test} from 'mocha';
+import {suite, suiteSetup, suiteTeardown, test} from './jest.js';
 import {assert} from 'chai';
 
 import {createStructClass} from './struct.js';

js/noms/src/xp-test.js

@@ -5,7 +5,7 @@
 // @flow
 
 import {assert} from 'chai';
-import {suite, test} from 'mocha';
+import {suite, test} from './jest.js';
 import type Value from './value.js';
 import {TestDatabase} from './test-util.js';
 import {equals} from './compare.js';