1 // Copyright 2012 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
5 // This file implements various error reporters.
11 "cmd/compile/internal/syntax"
17 func unimplemented() {
18 panic("unimplemented")
23 panic("assertion failed")
31 // An error_ represents a type-checking error.
32 // To report an error_, call Checker.report.
35 soft bool // TODO(gri) eventually determine this from an error code
38 // An errorDesc describes part of a type-checking error.
39 type errorDesc struct {
45 func (err *error_) empty() bool {
46 return err.desc == nil
49 func (err *error_) pos() syntax.Pos {
53 return err.desc[0].pos
56 func (err *error_) msg(qf Qualifier) string {
61 for i := range err.desc {
64 fmt.Fprint(&buf, "\n\t")
66 fmt.Fprintf(&buf, "%s: ", p.pos)
69 buf.WriteString(sprintf(qf, false, p.format, p.args...))
74 // String is for testing.
75 func (err *error_) String() string {
79 return fmt.Sprintf("%s: %s", err.pos(), err.msg(nil))
82 // errorf adds formatted error information to err.
83 // It may be called multiple times to provide additional information.
84 func (err *error_) errorf(at poser, format string, args ...interface{}) {
85 err.desc = append(err.desc, errorDesc{posFor(at), format, args})
88 func sprintf(qf Qualifier, debug bool, format string, args ...interface{}) string {
89 for i, arg := range args {
90 switch a := arg.(type) {
94 panic("got operand instead of *operand")
96 arg = operandString(a, qf)
100 arg = syntax.String(a)
104 for i, x := range a {
106 buf.WriteString(", ")
108 buf.WriteString(syntax.String(x))
113 arg = ObjectString(a, qf)
115 arg = typeString(a, qf, debug)
119 for i, x := range a {
121 buf.WriteString(", ")
123 buf.WriteString(typeString(x, qf, debug))
130 return fmt.Sprintf(format, args...)
133 func (check *Checker) qualifier(pkg *Package) string {
134 // Qualify the package unless it's the package being type-checked.
135 if pkg != check.pkg {
136 if check.pkgPathMap == nil {
137 check.pkgPathMap = make(map[string]map[string]bool)
138 check.seenPkgMap = make(map[*Package]bool)
139 check.markImports(check.pkg)
141 // If the same package name was used by multiple packages, display the full path.
142 if len(check.pkgPathMap[pkg.name]) > 1 {
143 return strconv.Quote(pkg.path)
150 // markImports recursively walks pkg and its imports, to record unique import
151 // paths in pkgPathMap.
152 func (check *Checker) markImports(pkg *Package) {
153 if check.seenPkgMap[pkg] {
156 check.seenPkgMap[pkg] = true
158 forName, ok := check.pkgPathMap[pkg.name]
160 forName = make(map[string]bool)
161 check.pkgPathMap[pkg.name] = forName
163 forName[pkg.path] = true
165 for _, imp := range pkg.imports {
166 check.markImports(imp)
170 func (check *Checker) sprintf(format string, args ...interface{}) string {
171 return sprintf(check.qualifier, false, format, args...)
174 func (check *Checker) report(err *error_) {
176 panic("no error to report")
178 check.err(err.pos(), err.msg(check.qualifier), err.soft)
181 func (check *Checker) trace(pos syntax.Pos, format string, args ...interface{}) {
182 fmt.Printf("%s:\t%s%s\n",
184 strings.Repeat(". ", check.indent),
185 sprintf(check.qualifier, true, format, args...),
189 // dump is only needed for debugging
190 func (check *Checker) dump(format string, args ...interface{}) {
191 fmt.Println(sprintf(check.qualifier, true, format, args...))
194 func (check *Checker) err(at poser, msg string, soft bool) {
195 // Cheap trick: Don't report errors with messages containing
196 // "invalid operand" or "invalid type" as those tend to be
197 // follow-on errors which don't add useful information. Only
198 // exclude them if these strings are not at the beginning,
199 // and only if we have at least one error already reported.
200 if check.firstErr != nil && (strings.Index(msg, "invalid operand") > 0 || strings.Index(msg, "invalid type") > 0) {
206 // If we are encountering an error while evaluating an inherited
207 // constant initialization expression, pos is the position of in
208 // the original expression, and not of the currently declared
209 // constant identifier. Use the provided errpos instead.
210 // TODO(gri) We may also want to augment the error message and
211 // refer to the position (pos) in the original expression.
212 if check.errpos.IsKnown() {
213 assert(check.iota != nil)
217 err := Error{pos, stripAnnotations(msg), msg, soft}
218 if check.firstErr == nil {
222 if check.conf.Trace {
223 check.trace(pos, "ERROR: %s", msg)
226 f := check.conf.Error
228 panic(bailout{}) // report only first error
234 invalidAST = "invalid AST: "
235 invalidArg = "invalid argument: "
236 invalidOp = "invalid operation: "
239 type poser interface {
243 func (check *Checker) error(at poser, msg string) {
244 check.err(at, msg, false)
247 func (check *Checker) errorf(at poser, format string, args ...interface{}) {
248 check.err(at, check.sprintf(format, args...), false)
251 func (check *Checker) softErrorf(at poser, format string, args ...interface{}) {
252 check.err(at, check.sprintf(format, args...), true)
255 func (check *Checker) versionErrorf(at poser, goVersion string, format string, args ...interface{}) {
256 msg := check.sprintf(format, args...)
257 if check.conf.CompilerErrorMessages {
258 msg = fmt.Sprintf("%s requires %s or later (-lang was set to %s; check go.mod)", msg, goVersion, check.conf.GoVersion)
260 msg = fmt.Sprintf("%s requires %s or later", msg, goVersion)
262 check.err(at, msg, true)
265 // posFor reports the left (= start) position of at.
266 func posFor(at poser) syntax.Pos {
267 switch x := at.(type) {
270 return syntax.StartPos(x.expr)
273 return syntax.StartPos(x)
278 // stripAnnotations removes internal (type) annotations from s.
279 func stripAnnotations(s string) string {
280 // Would like to use strings.Builder but it's not available in Go 1.4.
282 for _, r := range s {
283 // strip #'s and subscript digits
284 if r < '₀' || '₀'+10 <= r { // '₀' == U+2080
288 if b.Len() < len(s) {