| // Copyright 2010 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 contains the test for canonical struct tags. |
| |
| package main |
| |
| import ( |
| "go/ast" |
| "reflect" |
| "strconv" |
| ) |
| |
| func init() { |
| register("structtags", |
| "check that struct field tags have canonical format and apply to exported fields as needed", |
| checkCanonicalFieldTag, |
| field) |
| } |
| |
| // checkCanonicalFieldTag checks a struct field tag. |
| func checkCanonicalFieldTag(f *File, node ast.Node) { |
| field := node.(*ast.Field) |
| if field.Tag == nil { |
| return |
| } |
| |
| tag, err := strconv.Unquote(field.Tag.Value) |
| if err != nil { |
| f.Badf(field.Pos(), "unable to read struct tag %s", field.Tag.Value) |
| return |
| } |
| |
| // Check tag for validity by appending |
| // new key:value to end and checking that |
| // the tag parsing code can find it. |
| st := reflect.StructTag(tag + ` _gofix:"_magic"`) |
| if st.Get("_gofix") != "_magic" { |
| f.Badf(field.Pos(), "struct field tag %s not compatible with reflect.StructTag.Get", field.Tag.Value) |
| return |
| } |
| |
| // Check for use of json or xml tags with unexported fields. |
| |
| // Embedded struct. Nothing to do for now, but that |
| // may change, depending on what happens with issue 7363. |
| if len(field.Names) == 0 { |
| return |
| } |
| |
| if field.Names[0].IsExported() { |
| return |
| } |
| |
| for _, enc := range [...]string{"json", "xml"} { |
| if st.Get(enc) != "" { |
| f.Badf(field.Pos(), "struct field %s has %s tag but is not exported", field.Names[0].Name, enc) |
| return |
| } |
| } |
| } |
