feat(pass-style): Extract passStyleOf and friends from marshal into t…

…he new pass-style package (#1439)

packages/captp/src/captp.js

@@ -4,6 +4,12 @@
 
 // This logic was mostly lifted from @agoric/swingset-vat liveSlots.js
 // Defects in it are mfig's fault.
+//
+// @ts-ignore We actually mean the function, not the type,
+// but TS somehow no longer knows that -- following the extraction
+// of @endo/pass-style from @endo/marshal.
+// We're using @ts-ignore here because TS is inconsistent about whether this
+// line is an error. It is not locally, but it is under CI.
 import { Remotable, Far, makeMarshal, QCLASS } from '@endo/marshal';
 import { E, HandledPromise } from '@endo/eventual-send';
 import { isPromise, makePromiseKit } from '@endo/promise-kit';
@@ -326,6 +332,10 @@ export const makeCapTP = (
         }
         // A new remote presence
         // Use Remotable rather than Far to make a remote from a presence
+        //
+        // @ts-expect-error We actually mean the function, not the type,
+        // but TS somehow no longer knows that -- following the extraction
+        // of @endo/pass-style from @endo/marshal.
         val = Remotable(iface, undefined, pr.resPres());
       } else {
         // A new promise

packages/far/package.json

@@ -27,7 +27,7 @@
   "homepage": "https://github.com/endojs/endo#readme",
   "dependencies": {
     "@endo/eventual-send": "^0.16.9",
-    "@endo/marshal": "^0.8.2"
+    "@endo/pass-style": "^0.1.0"
   },
   "devDependencies": {
     "@endo/init": "^0.5.53",

packages/far/src/index.js

@@ -1,5 +1,5 @@
 export { E } from '@endo/eventual-send';
-export { Far, getInterfaceOf, passStyleOf } from '@endo/marshal';
+export { Far, getInterfaceOf, passStyleOf } from '@endo/pass-style';
 
 /**
  * @template Primary

packages/marshal/index.js

@@ -1,41 +1,17 @@
-export { mapIterable, filterIterable } from './src/helpers/iter-helpers.js';
-export {
-  PASS_STYLE,
-  isObject,
-  assertChecker,
-  getTag,
-  hasOwnPropertyOf,
-} from './src/helpers/passStyle-helpers.js';
-
-export { getErrorConstructor, toPassableError } from './src/helpers/error.js';
-export { getInterfaceOf } from './src/helpers/remotable.js';
-
-export {
-  nameForPassableSymbol,
-  passableSymbolForName,
-} from './src/helpers/symbol.js';
-
-export { passStyleOf, assertPassable } from './src/passStyleOf.js';
-
 export { deeplyFulfilled } from './src/deeplyFulfilled.js';
 
-export { makeTagged } from './src/makeTagged.js';
-export { Remotable, Far, ToFarFunction } from './src/make-far.js';
-
 export { QCLASS } from './src/encodeToCapData.js';
 export { makeMarshal } from './src/marshal.js';
 export { stringify, parse } from './src/marshal-stringify.js';
 
 export { decodeToJustin } from './src/marshal-justin.js';
 
-export {
-  assertRecord,
-  assertCopyArray,
-  assertRemotable,
-  isRemotable,
-  isRecord,
-  isCopyArray,
-} from './src/typeGuards.js';
-
 // eslint-disable-next-line import/export
 export * from './src/types.js';
+
+// For compatibility, but importers of these should instead import these
+// directly from `@endo/pass-style` or (if applicable) `@endo/far`.
+// @ts-expect-error TS only complains about this line when checking other
+// packages that depend on this one, like marshal. The complaint is about
+// repeatedly exported types. Specifically "Remotable".
+export * from '@endo/pass-style';

packages/marshal/package.json

@@ -38,6 +38,7 @@
   "dependencies": {
     "@endo/eventual-send": "^0.16.9",
     "@endo/nat": "^4.1.24",
+    "@endo/pass-style": "^0.1.0",
     "@endo/promise-kit": "^0.2.53"
   },
   "devDependencies": {

packages/marshal/src/deeplyFulfilled.js

@@ -2,9 +2,7 @@
 
 import { E } from '@endo/eventual-send';
 import { isPromise } from '@endo/promise-kit';
-import { getTag, isObject } from './helpers/passStyle-helpers.js';
-import { makeTagged } from './makeTagged.js';
-import { passStyleOf } from './passStyleOf.js';
+import { getTag, isObject, makeTagged, passStyleOf } from '@endo/pass-style';
 
 /** @typedef {import('./types.js').Passable} Passable */
 /** @template T @typedef {import('@endo/eventual-send').ERef<T>} ERef */

packages/marshal/src/dot-membrane.js

@@ -2,11 +2,8 @@
 /// <reference types="ses"/>
 
 import { E } from '@endo/eventual-send';
-import { isObject } from './helpers/passStyle-helpers.js';
-import { getInterfaceOf } from './helpers/remotable.js';
-import { Far } from './make-far.js';
+import { isObject, getInterfaceOf, Far, passStyleOf } from '@endo/pass-style';
 import { makeMarshal } from './marshal.js';
-import { passStyleOf } from './passStyleOf.js';
 
 const { fromEntries } = Object;
 const { ownKeys } = Reflect;

packages/marshal/src/encodePassable.js

@@ -1,13 +1,13 @@
 /* eslint-disable no-bitwise */
-import { getTag } from './helpers/passStyle-helpers.js';
-import { makeTagged } from './makeTagged.js';
-import { passStyleOf } from './passStyleOf.js';
-import { assertRecord } from './typeGuards.js';
 import {
+  getTag,
+  makeTagged,
+  passStyleOf,
+  assertRecord,
+  isErrorLike,
   nameForPassableSymbol,
   passableSymbolForName,
-} from './helpers/symbol.js';
-import { ErrorHelper } from './helpers/error.js';
+} from '@endo/pass-style';
 
 /** @typedef {import('./types.js').PassStyle} PassStyle */
 /** @typedef {import('./types.js').Passable} Passable */
@@ -305,7 +305,7 @@ export const makeEncodePassable = ({
   encodeError = (err, _) => Fail`error unexpected: ${err}`,
 } = {}) => {
   const encodePassable = passable => {
-    if (ErrorHelper.canBeValid(passable)) {
+    if (isErrorLike(passable)) {
       return encodeError(passable, encodePassable);
     }
     const passStyle = passStyleOf(passable);
@@ -470,6 +470,9 @@ harden(isEncodedRemotable);
  * prefix used by any cover so that ordinal mapping keys are always outside
  * the range of valid collection entry keys.
  */
+// @ts-expect-error TS does not understand thst `__proto__;` in this position
+// is special syntax. Instead, it complains that the `null` is not a string,
+// which would only make sense if this were defining a property.
 export const passStylePrefixes = harden({
   __proto__: null,
   error: '!',

packages/marshal/src/encodeToCapData.js

@@ -6,20 +6,17 @@
 // encodes to CapData, a JSON-representable data structure, and leaves it to
 // the caller (`marshal.js`) to stringify it.
 
-import { passStyleOf } from './passStyleOf.js';
-
-import { ErrorHelper } from './helpers/error.js';
-import { makeTagged } from './makeTagged.js';
 import {
+  passStyleOf,
+  isErrorLike,
+  makeTagged,
   isObject,
   getTag,
   hasOwnPropertyOf,
-} from './helpers/passStyle-helpers.js';
-import {
   assertPassableSymbol,
   nameForPassableSymbol,
   passableSymbolForName,
-} from './helpers/symbol.js';
+} from '@endo/pass-style';
 
 /** @typedef {import('./types.js').Passable} Passable */
 /** @typedef {import('./types.js').Encoding} Encoding */
@@ -249,7 +246,7 @@ export const makeEncodeToCapData = ({
     }
   };
   const encodeToCapData = passable => {
-    if (ErrorHelper.canBeValid(passable)) {
+    if (isErrorLike(passable)) {
       // We pull out this special case to accommodate errors that are not
       // valid Passables. For example, because they're not frozen.
       // The special case can only ever apply at the root, and therefore

packages/marshal/src/encodeToSmallcaps.js

@@ -6,16 +6,16 @@
 // encodes to Smallcaps, a JSON-representable data structure, and leaves it to
 // the caller (`marshal.js`) to stringify it.
 
-import { passStyleOf } from './passStyleOf.js';
-
-import { ErrorHelper } from './helpers/error.js';
-import { makeTagged } from './makeTagged.js';
-import { getTag, hasOwnPropertyOf } from './helpers/passStyle-helpers.js';
 import {
+  passStyleOf,
+  isErrorLike,
+  makeTagged,
+  getTag,
+  hasOwnPropertyOf,
   assertPassableSymbol,
   nameForPassableSymbol,
   passableSymbolForName,
-} from './helpers/symbol.js';
+} from '@endo/pass-style';
 
 /** @typedef {import('./types.js').Passable} Passable */
 /** @typedef {import('./types.js').Remotable} Remotable */
@@ -269,7 +269,7 @@ export const makeEncodeToSmallcaps = ({
     }
   };
   const encodeToSmallcaps = passable => {
-    if (ErrorHelper.canBeValid(passable)) {
+    if (isErrorLike(passable)) {
       // We pull out this special case to accommodate errors that are not
       // valid Passables. For example, because they're not frozen.
       // The special case can only ever apply at the root, and therefore

packages/marshal/src/marshal-justin.js

@@ -1,12 +1,13 @@
 /// <reference types="ses"/>
 
 import { Nat } from '@endo/nat';
+import {
+  getErrorConstructor,
+  isObject,
+  passableSymbolForName,
+} from '@endo/pass-style';
 import { QCLASS } from './encodeToCapData.js';
 
-import { getErrorConstructor } from './helpers/error.js';
-import { isObject } from './helpers/passStyle-helpers.js';
-import { AtAtPrefixPattern, passableSymbolForName } from './helpers/symbol.js';
-
 /** @typedef {import('./types.js').Encoding} Encoding */
 /** @template T @typedef {import('./types.js').CapData<T>} CapData */
 
@@ -112,6 +113,9 @@ const makeNoIndenter = () => {
 };
 
 const identPattern = /^[a-zA-Z]\w*$/;
+harden(identPattern);
+const AtAtPrefixPattern = /^@@(.*)$/;
+harden(AtAtPrefixPattern);
 
 /**
  * @param {Encoding} encoding

packages/marshal/src/marshal.js

@@ -1,10 +1,13 @@
 /// <reference types="ses"/>
 
 import { Nat } from '@endo/nat';
-import { assertPassable } from './passStyleOf.js';
+import {
+  assertPassable,
+  getInterfaceOf,
+  getErrorConstructor,
+  hasOwnPropertyOf,
+} from '@endo/pass-style';
 
-import { getInterfaceOf } from './helpers/remotable.js';
-import { getErrorConstructor } from './helpers/error.js';
 import {
   QCLASS,
   makeEncodeToCapData,
@@ -14,7 +17,6 @@ import {
   makeDecodeFromSmallcaps,
   makeEncodeToSmallcaps,
 } from './encodeToSmallcaps.js';
-import { hasOwnPropertyOf } from './helpers/passStyle-helpers.js';
 
 /** @typedef {import('./types.js').MakeMarshalOptions} MakeMarshalOptions */
 /** @template Slot @typedef {import('./types.js').ConvertSlotToVal<Slot>} ConvertSlotToVal */
@@ -99,7 +101,7 @@ export const makeMarshal = (
      * Even if an Error is not actually passable, we'd rather send
      * it anyway because the diagnostic info carried by the error
      * is more valuable than diagnosing why the error isn't
-     * passable. See comments in ErrorHelper.
+     * passable. See comments in isErrorLike.
      *
      * @param {Error} err
      * @param {(p: Passable) => unknown} encodeRecur
@@ -156,7 +158,7 @@ export const makeMarshal = (
        * Even if an Error is not actually passable, we'd rather send
        * it anyway because the diagnostic info carried by the error
        * is more valuable than diagnosing why the error isn't
-       * passable. See comments in ErrorHelper.
+       * passable. See comments in isErrorLike.
        *
        * @param {Error} err
        * @param {(p: Passable) => Encoding} encodeRecur
@@ -323,7 +325,13 @@ export const makeMarshal = (
     };
 
     const reviveFromSmallcaps = makeDecodeFromSmallcaps({
+      // @ts-expect-error This error started after separating pass-style
+      // out of marshal into its own package. Aside from that, I do not
+      // understand this error at all.
       decodeRemotableFromSmallcaps,
+      // @ts-expect-error This error started after separating pass-style
+      // out of marshal into its own package. Aside from that, I do not
+      // understand this error at all.
       decodePromiseFromSmallcaps,
       decodeErrorFromSmallcaps,
     });

packages/marshal/src/rankOrder.js

@@ -1,6 +1,4 @@
-import { getTag } from './helpers/passStyle-helpers.js';
-import { passStyleOf } from './passStyleOf.js';
-import { nameForPassableSymbol } from './helpers/symbol.js';
+import { getTag, passStyleOf, nameForPassableSymbol } from '@endo/pass-style';
 import {
   passStylePrefixes,
   recordNames,