blob: 91b077163c403f1080a09e69ac3c8e5c3f817595 [file] [log] [blame]
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file implements various error reporters.
package types
import (
func assert(p bool) {
if !p {
panic("assertion failed")
func unreachable() {
func (check *Checker) qualifier(pkg *Package) string {
// Qualify the package unless it's the package being type-checked.
if pkg != check.pkg {
// If the same package name was used by multiple packages, display the full path.
if check.pkgCnt[] > 1 {
return strconv.Quote(pkg.path)
return ""
func (check *Checker) sprintf(format string, args ...interface{}) string {
for i, arg := range args {
switch a := arg.(type) {
case nil:
arg = "<nil>"
case operand:
panic("internal error: should always pass *operand")
case *operand:
arg = operandString(a, check.qualifier)
case token.Pos:
arg = check.fset.Position(a).String()
case ast.Expr:
arg = ExprString(a)
case Object:
arg = ObjectString(a, check.qualifier)
case Type:
arg = TypeString(a, check.qualifier)
args[i] = arg
return fmt.Sprintf(format, args...)
func (check *Checker) trace(pos token.Pos, format string, args ...interface{}) {
strings.Repeat(". ", check.indent),
check.sprintf(format, args...),
// dump is only needed for debugging
func (check *Checker) dump(format string, args ...interface{}) {
fmt.Println(check.sprintf(format, args...))
func (check *Checker) err(pos token.Pos, msg string, soft bool) {
// Cheap trick: Don't report errors with messages containing
// "invalid operand" or "invalid type" as those tend to be
// follow-on errors which don't add useful information. Only
// exclude them if these strings are not at the beginning,
// and only if we have at least one error already reported.
if check.firstErr != nil && (strings.Index(msg, "invalid operand") > 0 || strings.Index(msg, "invalid type") > 0) {
err := Error{check.fset, pos, msg, soft}
if check.firstErr == nil {
check.firstErr = err
if trace {
check.trace(pos, "ERROR: %s", msg)
f := check.conf.Error
if f == nil {
panic(bailout{}) // report only first error
func (check *Checker) error(pos token.Pos, msg string) {
check.err(pos, msg, false)
func (check *Checker) errorf(pos token.Pos, format string, args ...interface{}) {
check.err(pos, check.sprintf(format, args...), false)
func (check *Checker) softErrorf(pos token.Pos, format string, args ...interface{}) {
check.err(pos, check.sprintf(format, args...), true)
func (check *Checker) invalidAST(pos token.Pos, format string, args ...interface{}) {
check.errorf(pos, "invalid AST: "+format, args...)
func (check *Checker) invalidArg(pos token.Pos, format string, args ...interface{}) {
check.errorf(pos, "invalid argument: "+format, args...)
func (check *Checker) invalidOp(pos token.Pos, format string, args ...interface{}) {
check.errorf(pos, "invalid operation: "+format, args...)