fix(time): give ParseError the exported fields of Go's ParseError

gs/time/time.ts

@@ -1259,31 +1259,69 @@ export function Weekday_String(w: Weekday): string {
   return WeekdayString(w)
 }
 
-// ParseError describes a problem parsing a time string.
-export class ParseError extends Error {
-  public layout: string
-  public value: string
-  public layoutElem: string
-  public valueElem: string
-  public message: string
+// ParseError describes a problem parsing a time string. It has the exported
+// fields of Go's ParseError, so Go code can make one with a composite literal
+// and match one with errors.As.
+export class ParseError {
+  public Layout: string
+  public Value: string
+  public LayoutElem: string
+  public ValueElem: string
+  public Message: string
 
   constructor(
-    layout: string,
-    value: string,
-    layoutElem: string,
-    valueElem: string,
-    message: string,
+    init?: Partial<{
+      Layout: string
+      Value: string
+      LayoutElem: string
+      ValueElem: string
+      Message: string
+    }>,
   ) {
-    super(message)
-    this.layout = layout
-    this.value = value
-    this.layoutElem = layoutElem
-    this.valueElem = valueElem
-    this.message = message
-    this.name = 'ParseError'
+    this.Layout = init?.Layout ?? ''
+    this.Value = init?.Value ?? ''
+    this.LayoutElem = init?.LayoutElem ?? ''
+    this.ValueElem = init?.ValueElem ?? ''
+    this.Message = init?.Message ?? ''
+  }
+
+  public clone(): ParseError {
+    return new ParseError(this)
+  }
+
+  // Error returns the string representation of a ParseError, as Go does.
+  public Error(): string {
+    if (this.Message === '') {
+      return (
+        'parsing time ' +
+        quoteParseValue(this.Value) +
+        ' as ' +
+        quoteParseValue(this.Layout) +
+        ': cannot parse ' +
+        quoteParseValue(this.ValueElem) +
+        ' as ' +
+        quoteParseValue(this.LayoutElem)
+      )
+    }
+    return 'parsing time ' + quoteParseValue(this.Value) + this.Message
   }
+
+  static __typeInfo: $.StructTypeInfo
 }
 
+// ParseError registers with the runtime type system, so that *ParseError
+// implements error for type assertions and errors.As.
+ParseError.__typeInfo = $.registerStructType(
+  'time.ParseError',
+  new ParseError(),
+  [{ name: 'Error', args: [], returns: [{ type: $.basicType('string') }] }],
+  ParseError,
+  () =>
+    ['Layout', 'Value', 'LayoutElem', 'ValueElem', 'Message'].map((name, i) =>
+      $.structField(name, $.basicType('string'), [i], i * 16, true),
+    ),
+)
+
 // Timer represents a single event timer. A Timer made without a duration is
 // the zero Timer, which does not run until it is Reset.
 export class Timer {
@@ -2185,18 +2223,13 @@ function newParseError(
   valueElem: string,
   message: string,
 ): $.GoError {
-  const text =
-    message === '' ?
-      'parsing time ' +
-      quoteParseValue(value) +
-      ' as ' +
-      quoteParseValue(layout) +
-      ': cannot parse ' +
-      quoteParseValue(valueElem) +
-      ' as ' +
-      quoteParseValue(layoutElem)
-    : 'parsing time ' + quoteParseValue(value) + message
-  return $.toGoError(new ParseError(layout, value, layoutElem, valueElem, text))
+  return new ParseError({
+    Layout: layout,
+    Value: value,
+    LayoutElem: layoutElem,
+    ValueElem: valueElem,
+    Message: message,
+  })
 }
 
 function isLeap(year: number): boolean {

tests/tests/package_import_time_parse_error/expected.log

@@ -0,0 +1,5 @@
+as: true
+fields: 2006-01-02 2024-13-01 : month out of range
+error: parsing time "2024-13-01": month out of range
+literal: parsing time "x" as "15:04": cannot parse "x" as "15"
+message: parsing time "y": bad

tests/tests/package_import_time_parse_error/package_import_time_parse_error.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"errors"
+	"time"
+)
+
+func main() {
+	// A parse failure is a *time.ParseError that errors.As finds.
+	_, err := time.Parse("2006-01-02", "2024-13-01")
+	var pe *time.ParseError
+	println("as:", errors.As(err, &pe))
+	println("fields:", pe.Layout, pe.Value, pe.Message)
+	println("error:", err.Error())
+
+	// A composite literal sets the exported fields, and Error formats them.
+	lit := &time.ParseError{Layout: "15:04", Value: "x", LayoutElem: "15", ValueElem: "x"}
+	println("literal:", lit.Error())
+	lit = &time.ParseError{Value: "y", Message: ": bad"}
+	println("message:", lit.Error())
+}

tests/tests/package_import_time_parse_error/package_import_time_parse_error.gs.ts

@@ -0,0 +1,27 @@
+// Generated file based on package_import_time_parse_error.go
+// Updated when compliance tests are re-run, DO NOT EDIT!
+
+import * as $ from "@goscript/builtin/index.js"
+import * as errors from "@goscript/errors/index.js"
+import * as time from "@goscript/time/index.js"
+
+export async function main(): globalThis.Promise<void> {
+	// A parse failure is a *time.ParseError that errors.As finds.
+	let [, err] = time.Parse("2006-01-02", "2024-13-01")
+	let pe: $.VarRef<time.ParseError | $.VarRef<time.ParseError> | null> = $.varRef(null! as time.ParseError | $.VarRef<time.ParseError> | null)
+	await $.println("as:", errors.As($.pointerValueOrNil(err)!, $.interfaceValue(pe, "**time.ParseError", /* @__PURE__ */ $.pointerType(/* @__PURE__ */ $.pointerType("time.ParseError")))))
+	await $.println("fields:", $.pointerValue<time.ParseError>(pe.value).Layout, $.pointerValue<time.ParseError>(pe.value).Value, $.pointerValue<time.ParseError>(pe.value).Message)
+	await $.println("error:", (__goscriptAwait = (err !== null && (err as any).__isVarRef !== true && ((err as any).__goValue === undefined || (err as any).__goType?.charCodeAt(0) !== 42) ? (err as Exclude<$.GoError, null>) : $.pointerValue<Exclude<$.GoError, null>>(err)).Error(), __goscriptAwait instanceof Promise ? await __goscriptAwait : __goscriptAwait))
+
+	// A composite literal sets the exported fields, and Error formats them.
+	let lit: time.ParseError | $.VarRef<time.ParseError> | null = new time.ParseError({Layout: "15:04", Value: "x", LayoutElem: "15", ValueElem: "x"})
+	await $.println("literal:", (lit !== null && (lit as any).__isVarRef !== true && (lit as any).__goValue === undefined ? ((lit as any) as time.ParseError).Error() : time.ParseError.prototype.Error.call($.pointerValue<time.ParseError>(lit))))
+	lit = new time.ParseError({Value: "y", Message: ": bad"})
+	await $.println("message:", (lit !== null && (lit as any).__isVarRef !== true && (lit as any).__goValue === undefined ? ((lit as any) as time.ParseError).Error() : time.ParseError.prototype.Error.call($.pointerValue<time.ParseError>(lit))))
+}
+
+var __goscriptAwait: any
+
+if ($.isMainScript(import.meta)) {
+	await main()
+}

tests/tests/package_import_time_parse_error/tsconfig.json

@@ -0,0 +1,25 @@
+{
+  "compilerOptions": {
+    "paths": {
+      "*": [
+        "./*"
+      ],
+      "@go/github.com/s4wave/goscript/*": [
+        "../../../*"
+      ],
+      "@goscript/*": [
+        "../../../tests/tests/package_import_time_parse_error/run/output/@goscript/*",
+        "../../../gs/*",
+        "../../../tests/deps/*"
+      ],
+      "@goscript/github.com/s4wave/goscript/tests/tests/package_import_time_parse_error/*": [
+        "./*"
+      ]
+    }
+  },
+  "extends": "../../../tests/tsconfig.base.json",
+  "include": [
+    "index.ts",
+    "package_import_time_parse_error.gs.ts"
+  ]
+}