replace UnionMember with Union

.changeset/gentle-readers-call.md

@@ -4,5 +4,6 @@
 
 Refactor `ParseResult` module:
 
+- replace `UnionMember` with `Union`
 - rename `UnionMember` to `Member`
 - ast `ast` field to `Member`

docs/modules/ParseResult.ts.md

@@ -23,6 +23,7 @@ Added in v1.0.0
   - [try](#try)
   - [type](#type)
   - [unexpected](#unexpected)
+  - [union](#union)
 - [model](#model)
   - [Forbidden (interface)](#forbidden-interface)
   - [Index (interface)](#index-interface)
@@ -32,6 +33,7 @@ Added in v1.0.0
   - [ParseIssue (type alias)](#parseissue-type-alias)
   - [Type (interface)](#type-interface)
   - [Unexpected (interface)](#unexpected-interface)
+  - [Union (interface)](#union-interface)
 - [optimisation](#optimisation)
   - [bimap](#bimap)
   - [eitherOrUndefined](#eitherorundefined)
@@ -150,6 +152,19 @@ export declare const unexpected: (ast: Option.Option<AST.AST>) => Unexpected
 
 Added in v1.0.0
 
+## union
+
+**Signature**
+
+```ts
+export declare const union: (
+  ast: AST.Union,
+  errors: readonly [Key | Type | Member, ...(Key | Type | Member)[]]
+) => Union
+```
+
+Added in v1.0.0
+
 # model
 
 ## Forbidden (interface)
@@ -246,7 +261,7 @@ export type ParseIssue =
   // context
   | Index
   | Key
-  | Member
+  | Union
   // primitives
   | Type
   | Missing
@@ -292,6 +307,22 @@ export interface Unexpected {
 
 Added in v1.0.0
 
+## Union (interface)
+
+Error that occurs when a union has an error.
+
+**Signature**
+
+```ts
+export interface Union {
+  readonly _tag: "Union"
+  readonly ast: AST.Union
+  readonly errors: ReadonlyArray.NonEmptyReadonlyArray<Member | Key | Type>
+}
+```
+
+Added in v1.0.0
+
 # optimisation
 
 ## bimap

src/ArrayFormatter.ts

@@ -25,8 +25,6 @@ const format = (self: ParseIssue, path: ReadonlyArray<PropertyKey> = []): Array<
       return ReadonlyArray.flatMap(self.errors, (e) => format(e, [...path, self.key]))
     case "Index":
       return ReadonlyArray.flatMap(self.errors, (e) => format(e, [...path, self.index]))
-    case "Member":
-      return ReadonlyArray.flatMap(self.errors, (e) => format(e, path))
     case "Missing":
       return [{ _tag, path, message: "Missing key or index" }]
     case "Forbidden":
@@ -38,6 +36,16 @@ const format = (self: ParseIssue, path: ReadonlyArray<PropertyKey> = []): Array<
         message: "Unexpected" +
           (Option.isSome(self.ast) ? `, expected ${formatExpected(self.ast.value)}` : "")
       }]
+    case "Union":
+      return ReadonlyArray.flatMap(self.errors, (e) => {
+        switch (e._tag) {
+          case "Key":
+          case "Type":
+            return format(e, path)
+          case "Member":
+            return ReadonlyArray.flatMap(e.errors, (e) => format(e, path))
+        }
+      })
   }
 }
 

src/ParseResult.ts

@@ -58,7 +58,7 @@ export type ParseIssue =
   // context
   | Index
   | Key
-  | Member
+  | Union
   // primitives
   | Type
   | Missing
@@ -195,6 +195,27 @@ export const unexpected = (
   ast: Option.Option<AST.AST>
 ): Unexpected => ({ _tag: "Unexpected", ast })
 
+/**
+ * Error that occurs when a union has an error.
+ *
+ * @category model
+ * @since 1.0.0
+ */
+export interface Union {
+  readonly _tag: "Union"
+  readonly ast: AST.Union
+  readonly errors: ReadonlyArray.NonEmptyReadonlyArray<Member | Key | Type>
+}
+
+/**
+ * @category constructors
+ * @since 1.0.0
+ */
+export const union = (
+  ast: AST.Union,
+  errors: ReadonlyArray.NonEmptyReadonlyArray<Member | Key | Type>
+): Union => ({ _tag: "Union", ast, errors })
+
 /**
  * Error that occurs when a member in a union has an error.
  *

src/Parser.ts

@@ -796,7 +796,7 @@ const go = (ast: AST.AST, isDecoding: boolean): Parser<any, any> => {
         map.set(ast.types[i], goMemo(ast.types[i], isDecoding))
       }
       return (input, options) => {
-        const es: Array<[number, ParseResult.ParseIssue]> = []
+        const es: Array<[number, ParseResult.Member | ParseResult.Key | ParseResult.Type]> = []
         let stepKey = 0
         let candidates: Array<AST.AST> = []
         if (len > 0) {
@@ -885,7 +885,7 @@ const go = (ast: AST.AST, isDecoding: boolean): Parser<any, any> => {
         // ---------------------------------------------
         const computeResult = (es: State["es"]) =>
           ReadonlyArray.isNonEmptyArray(es) ?
-            ParseResult.fail(sortByIndex(es)) :
+            ParseResult.fail(ParseResult.union(ast, sortByIndex(es))) :
             // this should never happen
             ParseResult.fail(ParseResult.type(AST.neverKeyword, input))
 

src/TreeFormatter.ts

@@ -136,7 +136,7 @@ export const formatExpected = (ast: AST.AST): string => {
 }
 
 const isCollapsible = (es: Forest<string>, errors: NonEmptyReadonlyArray<ParseIssue>): boolean =>
-  es.length === 1 && es[0].forest.length !== 0 && errors[0]._tag !== "Member"
+  es.length === 1 && es[0].forest.length !== 0 && errors[0]._tag !== "Union"
 
 /** @internal */
 export const getMessage = (e: Type) =>
@@ -174,10 +174,18 @@ const go = (e: ParseIssue): Tree<string> => {
     }
     case "Missing":
       return make("is missing")
-    case "Member":
+    case "Union":
       return make(
-        `union member: ${formatExpected(e.ast)}`,
-        e.errors.map(go)
+        `Union (${e.ast.types.length} members): ` + formatExpected(e.ast),
+        e.errors.map((e) => {
+          switch (e._tag) {
+            case "Key":
+            case "Type":
+              return go(e)
+            case "Member":
+              return make(`Union member: ${formatExpected(e.ast)}`, e.errors.map(go))
+          }
+        })
       )
   }
 }

test/Cause/cause.test.ts

@@ -78,7 +78,7 @@ describe("Cause/cause", () => {
     await Util.expectParseFailure(
       schema,
       { _tag: "Parallel", left: { _tag: "Fail" }, right: { _tag: "Interrupt" } },
-      `union member: /left union member: /error is missing`
+      `Union member: /left Union member: /error is missing`
     )
   })
 

test/Cause/causeFromSelf.test.ts

@@ -19,12 +19,12 @@ describe("Cause/causeFromSelf", () => {
     await Util.expectParseFailure(
       schema,
       Cause.fail("a"),
-      `union member: /error Expected <anonymous transformation string <-> number>, actual "a"`
+      `Union member: /error Expected <anonymous transformation string <-> number>, actual "a"`
     )
     await Util.expectParseFailure(
       schema,
       Cause.parallel(Cause.die("error"), Cause.fail("a")),
-      `union member: /right union member: /error Expected <anonymous transformation string <-> number>, actual "a"`
+      `Union member: /right Union member: /error Expected <anonymous transformation string <-> number>, actual "a"`
     )
   })
 

test/FiberId/FiberId.test.ts

@@ -26,7 +26,7 @@ describe("FiberId", () => {
     await Util.expectParseFailure(
       schema,
       { _tag: "Composite", left: { _tag: "None" }, right: { _tag: "-" } },
-      `union member: /right /_tag Expected "Composite" or "Runtime" or "None", actual "-"`
+      `Union member: /right /_tag Expected "Composite" or "Runtime" or "None", actual "-"`
     )
   })
 })

test/Option/optionFromNullable.test.ts

@@ -19,12 +19,12 @@ describe("Option/optionFromNullable", () => {
     await Util.expectParseFailure(
       schema,
       undefined,
-      `union member: Expected null, actual undefined, union member: Expected string, actual undefined`
+      `Union member: Expected null, actual undefined, Union member: Expected string, actual undefined`
     )
     await Util.expectParseFailure(
       schema,
       {},
-      `union member: Expected null, actual {}, union member: Expected string, actual {}`
+      `Union member: Expected null, actual {}, Union member: Expected string, actual {}`
     )
   })
 

test/Option/optionFromNullish.test.ts

@@ -22,7 +22,7 @@ describe("Option/optionFromNullish", () => {
     await Util.expectParseFailure(
       schema,
       {},
-      `union member: Expected null, actual {}, union member: Expected undefined, actual {}, union member: Expected string, actual {}`
+      `Union member: Expected null, actual {}, Union member: Expected undefined, actual {}, Union member: Expected string, actual {}`
     )
   })
 

test/Schema/Forbidden.test.ts

@@ -43,7 +43,7 @@ describe("Schema/Forbidden", () => {
     expectForbidden(
       S.union(S.string, S.string.pipe(S.minLength(2))),
       "a",
-      `union member: is forbidden, union member: is forbidden`
+      `Union member: is forbidden, Union member: is forbidden`
     )
   })
 

test/Schema/literal.test.ts

@@ -36,10 +36,11 @@ describe("Schema/literal", () => {
         schema,
         null,
         `error(s) found
-├─ union member: 1
-│  └─ Expected 1, actual null
-└─ union member: "a"
-   └─ Expected "a", actual null`
+└─ Union (2 members): 1 or "a"
+   ├─ Union member: 1
+   │  └─ Expected 1, actual null
+   └─ Union member: "a"
+      └─ Expected "a", actual null`
       )
     })
   })

test/Schema/onExcess.test.ts

@@ -29,7 +29,7 @@ describe("Schema/onExcess", () => {
       await Util.expectParseFailure(
         schema,
         { a: 1, b: "b", c: true },
-        `union member: /c is unexpected, expected "a" or "b", union member: /b is unexpected, expected "a"`,
+        `Union member: /c is unexpected, expected "a" or "b", Union member: /b is unexpected, expected "a"`,
         Util.onExcessPropertyError
       )
       await Util.expectEncodeSuccess(
@@ -52,12 +52,12 @@ describe("Schema/onExcess", () => {
       await Util.expectParseFailure(
         schema,
         [1, "b", true],
-        `union member: /2 is unexpected, union member: /1 is unexpected`
+        `Union member: /2 is unexpected, Union member: /1 is unexpected`
       )
       await Util.expectParseFailure(
         schema,
         [1, "b", true],
-        `union member: /2 is unexpected, union member: /1 is unexpected`,
+        `Union member: /2 is unexpected, Union member: /1 is unexpected`,
         Util.onExcessPropertyError
       )
       await Util.expectEncodeSuccess(

test/Schema/optional.test.ts

@@ -39,7 +39,7 @@ describe("optional APIs", () => {
       await Util.expectParseFailure(
         schema,
         { a: "a" },
-        `/a union member: Expected undefined, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected undefined, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, {}, {})
@@ -77,7 +77,7 @@ describe("optional APIs", () => {
         {
           a: "a"
         },
-        `/a union member: Expected null, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected null, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: O.some(1) }, { a: "1" })
@@ -96,7 +96,7 @@ describe("optional APIs", () => {
         {
           a: "a"
         },
-        `/a union member: Expected undefined, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected undefined, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: O.some(1) }, { a: "1" })
@@ -118,7 +118,7 @@ describe("optional APIs", () => {
         {
           a: "a"
         },
-        `/a union member: Expected null, actual "a", union member: Expected undefined, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected null, actual "a", Union member: Expected undefined, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: O.some(1) }, { a: "1" })
@@ -155,7 +155,7 @@ describe("optional APIs", () => {
       await Util.expectParseFailure(
         schema,
         { a: "a" },
-        `/a union member: Expected undefined, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected undefined, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: 1 }, { a: "1" })
@@ -175,7 +175,7 @@ describe("optional APIs", () => {
       await Util.expectParseFailure(
         schema,
         { a: "a" },
-        `/a union member: Expected null, actual "a", union member: Expected undefined, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected null, actual "a", Union member: Expected undefined, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: 1 }, { a: "1" })
@@ -194,7 +194,7 @@ describe("optional APIs", () => {
       await Util.expectParseFailure(
         schema,
         { a: "a" },
-        `/a union member: Expected null, actual "a", union member: Expected <anonymous transformation string <-> number>, actual "a"`
+        `/a Union member: Expected null, actual "a", Union member: Expected <anonymous transformation string <-> number>, actual "a"`
       )
 
       await Util.expectEncodeSuccess(schema, { a: 1 }, { a: "1" })