| // Copyright 2020 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. |
| |
| // Invoke with //go:generate helper/helper -t Server -d protocol/tsserver.go -u lsp -o server_gen.go |
| // invoke in internal/lsp |
| package main |
| |
| import ( |
| "bytes" |
| "flag" |
| "fmt" |
| "go/ast" |
| "go/format" |
| "go/parser" |
| "go/token" |
| "log" |
| "os" |
| "sort" |
| "strings" |
| "text/template" |
| ) |
| |
| var ( |
| typ = flag.String("t", "Server", "generate code for this type") |
| def = flag.String("d", "", "the file the type is defined in") // this relies on punning |
| use = flag.String("u", "", "look for uses in this package") |
| out = flag.String("o", "", "where to write the generated file") |
| ) |
| |
| func main() { |
| log.SetFlags(log.Lshortfile) |
| flag.Parse() |
| if *typ == "" || *def == "" || *use == "" || *out == "" { |
| flag.PrintDefaults() |
| return |
| } |
| // read the type definition and see what methods we're looking for |
| doTypes() |
| |
| // parse the package and see which methods are defined |
| doUses() |
| |
| output() |
| } |
| |
| // replace "\\\n" with nothing before using |
| var tmpl = ` |
| package lsp |
| |
| // code generated by helper. DO NOT EDIT. |
| |
| import ( |
| "context" |
| |
| "golang.org/x/tools/internal/lsp/protocol" |
| ) |
| |
| {{range $key, $v := .Stuff}} |
| func (s *{{$.Type}}) {{$v.Name}}({{.Param}}) {{.Result}} { |
| {{if ne .Found ""}} return s.{{.Internal}}({{.Invoke}})\ |
| {{else}}return {{if lt 1 (len .Results)}}nil, {{end}}notImplemented("{{.Name}}"){{end}} |
| } |
| {{end}} |
| ` |
| |
| func output() { |
| // put in empty param names as needed |
| for _, t := range types { |
| if t.paramnames == nil { |
| t.paramnames = make([]string, len(t.paramtypes)) |
| } |
| for i, p := range t.paramtypes { |
| cm := "" |
| if i > 0 { |
| cm = ", " |
| } |
| t.Param += fmt.Sprintf("%s%s %s", cm, t.paramnames[i], p) |
| this := t.paramnames[i] |
| if this == "_" { |
| this = "nil" |
| } |
| t.Invoke += fmt.Sprintf("%s%s", cm, this) |
| } |
| if len(t.Results) > 1 { |
| t.Result = "(" |
| } |
| for i, r := range t.Results { |
| cm := "" |
| if i > 0 { |
| cm = ", " |
| } |
| t.Result += fmt.Sprintf("%s%s", cm, r) |
| } |
| if len(t.Results) > 1 { |
| t.Result += ")" |
| } |
| } |
| |
| fd, err := os.Create(*out) |
| if err != nil { |
| log.Fatal(err) |
| } |
| t, err := template.New("foo").Parse(tmpl) |
| if err != nil { |
| log.Fatal(err) |
| } |
| type par struct { |
| Type string |
| Stuff []*Function |
| } |
| p := par{*typ, types} |
| if false { // debugging the template |
| t.Execute(os.Stderr, &p) |
| } |
| buf := bytes.NewBuffer(nil) |
| err = t.Execute(buf, &p) |
| if err != nil { |
| log.Fatal(err) |
| } |
| ans, err := format.Source(bytes.Replace(buf.Bytes(), []byte("\\\n"), []byte{}, -1)) |
| if err != nil { |
| log.Fatal(err) |
| } |
| fd.Write(ans) |
| } |
| |
| func doUses() { |
| fset := token.NewFileSet() |
| pkgs, err := parser.ParseDir(fset, *use, nil, 0) |
| if err != nil { |
| log.Fatalf("%q:%v", *use, err) |
| } |
| pkg := pkgs["lsp"] // CHECK |
| files := pkg.Files |
| for fname, f := range files { |
| for _, d := range f.Decls { |
| fd, ok := d.(*ast.FuncDecl) |
| if !ok { |
| continue |
| } |
| nm := fd.Name.String() |
| if ast.IsExported(nm) { |
| // we're looking for things like didChange |
| continue |
| } |
| if fx, ok := byname[nm]; ok { |
| if fx.Found != "" { |
| log.Fatalf("found %s in %s and %s", fx.Internal, fx.Found, fname) |
| } |
| fx.Found = fname |
| // and the Paramnames |
| ft := fd.Type |
| for _, f := range ft.Params.List { |
| nm := "" |
| if len(f.Names) > 0 { |
| nm = f.Names[0].String() |
| } |
| fx.paramnames = append(fx.paramnames, nm) |
| } |
| } |
| } |
| } |
| if false { |
| for i, f := range types { |
| log.Printf("%d %s %s", i, f.Internal, f.Found) |
| } |
| } |
| } |
| |
| type Function struct { |
| Name string |
| Internal string // first letter lower case |
| paramtypes []string |
| paramnames []string |
| Results []string |
| Param string |
| Result string // do it in code, easier than in a template |
| Invoke string |
| Found string // file it was found in |
| } |
| |
| var types []*Function |
| var byname = map[string]*Function{} // internal names |
| |
| func doTypes() { |
| fset := token.NewFileSet() |
| f, err := parser.ParseFile(fset, *def, nil, 0) |
| if err != nil { |
| log.Fatal(err) |
| } |
| fd, err := os.Create("/tmp/ast") |
| if err != nil { |
| log.Fatal(err) |
| } |
| ast.Fprint(fd, fset, f, ast.NotNilFilter) |
| ast.Inspect(f, inter) |
| sort.Slice(types, func(i, j int) bool { return types[i].Name < types[j].Name }) |
| if false { |
| for i, f := range types { |
| log.Printf("%d %s(%v) %v", i, f.Name, f.paramtypes, f.Results) |
| } |
| } |
| } |
| |
| func inter(n ast.Node) bool { |
| x, ok := n.(*ast.TypeSpec) |
| if !ok || x.Name.Name != *typ { |
| return true |
| } |
| m := x.Type.(*ast.InterfaceType).Methods.List |
| for _, fld := range m { |
| fn := fld.Type.(*ast.FuncType) |
| p := fn.Params.List |
| r := fn.Results.List |
| fx := &Function{ |
| Name: fld.Names[0].String(), |
| } |
| fx.Internal = strings.ToLower(fx.Name[:1]) + fx.Name[1:] |
| for _, f := range p { |
| fx.paramtypes = append(fx.paramtypes, whatis(f.Type)) |
| } |
| for _, f := range r { |
| fx.Results = append(fx.Results, whatis(f.Type)) |
| } |
| types = append(types, fx) |
| byname[fx.Internal] = fx |
| } |
| return false |
| } |
| |
| func whatis(x ast.Expr) string { |
| switch n := x.(type) { |
| case *ast.SelectorExpr: |
| return whatis(n.X) + "." + n.Sel.String() |
| case *ast.StarExpr: |
| return "*" + whatis(n.X) |
| case *ast.Ident: |
| if ast.IsExported(n.Name) { |
| // these are from package protocol |
| return "protocol." + n.Name |
| } |
| return n.Name |
| case *ast.ArrayType: |
| return "[]" + whatis(n.Elt) |
| case *ast.InterfaceType: |
| return "interface{}" |
| default: |
| log.Fatalf("Fatal %T", x) |
| return fmt.Sprintf("%T", x) |
| } |
| } |