microsoft/typescript-go · error · ErrClientError

%w: failed to decode AST: %w

Error message

%w: failed to decode AST: %w

What it means

Error "%w: failed to decode AST: %w" thrown in microsoft/typescript-go.

Source

Thrown at internal/api/session.go:2506

		}
	}

	if params.Flags != 0 {
		return setup.checker.TypeToStringEx(t, enclosingDeclaration, checker.TypeFormatFlags(params.Flags), nil), nil
	}
	return setup.checker.TypeToStringEx(t, enclosingDeclaration, checker.TypeFormatFlagsAllowUniqueESSymbolType|checker.TypeFormatFlagsUseAliasDefinedOutsideCurrentScope, nil), nil
}

// handlePrintNode decodes a binary-encoded AST node and prints it to text.
func (s *Session) handlePrintNode(_ context.Context, params *PrintNodeParams) (string, error) {
	data, err := base64.StdEncoding.DecodeString(params.Data)
	if err != nil {
		return "", fmt.Errorf("%w: invalid base64 data: %w", ErrClientError, err)
	}

	node, err := encoder.DecodeNodes(data)
	if err != nil {
		return "", fmt.Errorf("%w: failed to decode AST: %w", ErrClientError, err)
	}

	p := printer.NewPrinter(printer.PrinterOptions{
		PreserveSourceNewlines:        params.PreserveSourceNewlines,
		NeverAsciiEscape:              params.NeverAsciiEscape,
		TerminateUnterminatedLiterals: params.TerminateUnterminatedLiterals,
	}, printer.PrintHandlers{}, nil)
	return p.Emit(node, nil), nil
}

func (s *Session) handleEmit(ctx context.Context, params *EmitParams) (*EmitResponse, error) {
	program, options, err := s.getEmitOptions(params)
	if err != nil {
		return nil, err
	}
	options.WriteFile = func(fileName string, text string, _ *compiler.WriteFileData) error {
		return s.projectSession.FS().WriteFile(fileName, text)
	}

View on GitHub (pinned to 1bcfa18d79)

When it happens

Trigger: Thrown at internal/api/session.go:2506 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

AI-assisted analysis of microsoft/typescript-go@1bcfa18d79 (2026-08-16). Data as JSON: /api/errors/f7514e93cb344da6. Report an issue: GitHub.