From 95a15ae31e4a6fcd203ccc3bc7c6c74b63c31ce1 Mon Sep 17 00:00:00 2001 From: Michael Wolber Date: Thu, 4 Jan 2018 11:38:06 +0100 Subject: [PATCH] Updated stringer.go to current version (2018/01) --- stringer.go | 120 ++++++++++++++++++++-------------------------------- 1 file changed, 47 insertions(+), 73 deletions(-) diff --git a/stringer.go b/stringer.go index fa7c383..e3f5067 100644 --- a/stringer.go +++ b/stringer.go @@ -2,8 +2,6 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build go1.5 - // Stringer is a tool to automate the creation of methods that satisfy the fmt.Stringer // interface. Given the name of a (signed or unsigned) integer type T that has constants // defined, stringer will create a new self-contained Go source file implementing @@ -58,8 +56,8 @@ // where t is the lower-cased name of the first type listed. It can be overridden // with the -output flag. // -// ------ -// This is a patched versin of the original stringer. The original generates source code +// ----------------- +// This is a patched version of the original stringer. The original generates source code // using '_' (underscore) as part of generated golang identifiers. This creates a number of // golint warnings. The patched version simply leaves the '_' out @@ -86,12 +84,10 @@ import ( ) var ( - typeNames = flag.String("type", "", "comma-separated list of type names; must be set") - sql = flag.Bool("sql", false, "if true, the Scanner and Valuer interface will be implemented.") - json = flag.Bool("json", false, "if true, json marshaling methods will be generated. Default: false") - yaml = flag.Bool("yaml", false, "if true, yaml marshaling methods will be generated. Default: false") - output = flag.String("output", "", "output file name; default srcdir/_string.go") - transformMethod = flag.String("transform", "noop", "enum item name transformation method. Default: noop") + typeNames = flag.String("type", "", "comma-separated list of type names; must be set") + output = flag.String("output", "", "output file name; default srcdir/_string.go") + trimprefix = flag.String("trimprefix", "", "trim the `prefix` from the generated constant names") + linecomment = flag.Bool("linecomment", false, "use line comment text as printed text when present") ) // Usage is a replacement usage function for the flags package. @@ -107,7 +103,7 @@ func Usage() { func main() { log.SetFlags(0) - log.SetPrefix("enumer: ") + log.SetPrefix("stringer: ") flag.Usage = Usage flag.Parse() if len(*typeNames) == 0 { @@ -124,11 +120,11 @@ func main() { } // Parse the package once. - var ( - dir string - g Generator - ) - + var dir string + g := Generator{ + trimPrefix: *trimprefix, + lineComment: *linecomment, + } if len(args) == 1 && isDirectory(args[0]) { dir = args[0] g.parsePackageDir(args[0]) @@ -138,23 +134,15 @@ func main() { } // Print the header and package clause. - g.Printf("// Code generated by \"enumer %s\"; DO NOT EDIT\n", strings.Join(os.Args[1:], " ")) + g.Printf("// Code generated by \"stringer %s\"; DO NOT EDIT.\n", strings.Join(os.Args[1:], " ")) g.Printf("\n") g.Printf("package %s", g.pkg.name) g.Printf("\n") - g.Printf("import (\n") - g.Printf("\t\"fmt\"\n") - if *sql { - g.Printf("\t\"database/sql/driver\"\n") - } - if *json { - g.Printf("\t\"encoding/json\"\n") - } - g.Printf(")\n") + g.Printf("import \"strconv\"\n") // Used by all methods. // Run generate for each type. for _, typeName := range types { - g.generate(typeName, *json, *yaml, *sql, *transformMethod) + g.generate(typeName) } // Format the output. @@ -186,6 +174,9 @@ func isDirectory(name string) bool { type Generator struct { buf bytes.Buffer // Accumulated output. pkg *Package // Package we are scanning. + + trimPrefix string + lineComment bool } func (g *Generator) Printf(format string, args ...interface{}) { @@ -199,6 +190,9 @@ type File struct { // These fields are reset for each type being generated. typeName string // Name of the constant type. values []Value // Accumulator for constant values of that type. + + trimPrefix string + lineComment bool } type Package struct { @@ -255,14 +249,16 @@ func (g *Generator) parsePackage(directory string, names []string, text interfac if !strings.HasSuffix(name, ".go") { continue } - parsedFile, err := parser.ParseFile(fs, name, text, 0) + parsedFile, err := parser.ParseFile(fs, name, text, parser.ParseComments) if err != nil { log.Fatalf("parsing package: %s: %s", name, err) } astFiles = append(astFiles, parsedFile) files = append(files, &File{ - file: parsedFile, - pkg: g.pkg, + file: parsedFile, + pkg: g.pkg, + trimPrefix: g.trimPrefix, + lineComment: g.lineComment, }) } if len(astFiles) == 0 { @@ -289,24 +285,8 @@ func (pkg *Package) check(fs *token.FileSet, astFiles []*ast.File) { pkg.typesPkg = typesPkg } -func (g *Generator) transformValueNames(values []Value, transformMethod string) { - var transform func(string) string - switch transformMethod { - case "snake": - transform = toSnakeCase - case "kebab": - transform = toKebabCase - default: - return - } - - for i := range values { - values[i].name = transform(values[i].name) - } -} - // generate produces the String method for the named type. -func (g *Generator) generate(typeName string, includeJSON, includeYAML, includeSQL bool, transformMethod string) { +func (g *Generator) generate(typeName string) { values := make([]Value, 0, 100) for _, file := range g.pkg.files { // Set the state for this run of the walker. @@ -321,9 +301,6 @@ func (g *Generator) generate(typeName string, includeJSON, includeYAML, includeS if len(values) == 0 { log.Fatalf("no values defined for type %s", typeName) } - - g.transformValueNames(values, transformMethod) - runs := splitIntoRuns(values) // The decision of which pattern to use depends on the number of // runs in the numbers. If there's only one, it's easy. For more than @@ -337,26 +314,14 @@ func (g *Generator) generate(typeName string, includeJSON, includeYAML, includeS // being necessary for any realistic example other than bitmasks // is very low. And bitmasks probably deserve their own analysis, // to be done some other day. - const runsThreshold = 10 switch { case len(runs) == 1: g.buildOneRun(runs, typeName) - case len(runs) <= runsThreshold: + case len(runs) <= 10: g.buildMultipleRuns(runs, typeName) default: g.buildMap(runs, typeName) } - - g.buildValueToNameMap(runs, typeName, runsThreshold) - if includeJSON { - g.buildJSONMethods(runs, typeName, runsThreshold) - } - if includeYAML { - g.buildYAMLMethods(runs, typeName, runsThreshold) - } - if includeSQL { - g.addValueAndScanMethod(typeName) - } } // splitIntoRuns breaks the values into runs of contiguous sequences. @@ -406,7 +371,7 @@ func (g *Generator) format() []byte { // Value represents a declared constant. type Value struct { - name string // The name of the constant after transformation (i.e. camel case => snake case) + name string // The name of the constant. // The value is stored as a bit pattern alone. The boolean tells us // whether to interpret it as an int64 or a uint64; the only place // this matters is when sorting. @@ -505,6 +470,10 @@ func (f *File) genDecl(node ast.Node) bool { signed: info&types.IsUnsigned == 0, str: value.String(), } + if c := vspec.Comment; f.lineComment && c != nil && len(c.List) == 1 { + v.name = strings.TrimSpace(c.Text()) + } + v.name = strings.TrimPrefix(v.name, f.trimPrefix) f.values = append(f.values, v) } } @@ -534,7 +503,9 @@ func (g *Generator) declareIndexAndNameVars(runs [][]Value, typeName string) { var indexes, names []string for i, run := range runs { index, name := g.createIndexAndNameDecl(run, typeName, fmt.Sprintf("_%d", i)) - indexes = append(indexes, index) + if len(run) != 1 { + indexes = append(indexes, index) + } names = append(names, name) } g.Printf("const (\n") @@ -542,11 +513,14 @@ func (g *Generator) declareIndexAndNameVars(runs [][]Value, typeName string) { g.Printf("\t%s\n", name) } g.Printf(")\n\n") - g.Printf("var (") - for _, index := range indexes { - g.Printf("\t%s\n", index) + + if len(indexes) > 0 { + g.Printf("var (") + for _, index := range indexes { + g.Printf("\t%s\n", index) + } + g.Printf(")\n\n") } - g.Printf(")\n\n") } // declareIndexAndNameVar is the single-run version of declareIndexAndNameVars @@ -612,7 +586,7 @@ func (g *Generator) buildOneRun(runs [][]Value, typeName string) { // [3]: less than zero check (for signed types) const stringOneRun = `func (i %[1]s) String() string { if %[3]si >= %[1]s(len(_%[1]sIndex)-1) { - return fmt.Sprintf("%[1]s(%%d)", i) + return "%[1]s(" + strconv.FormatInt(int64(i), 10) + ")" } return _%[1]sName[_%[1]sIndex[i]:_%[1]sIndex[i+1]] } @@ -628,7 +602,7 @@ const stringOneRun = `func (i %[1]s) String() string { const stringOneRunWithOffset = `func (i %[1]s) String() string { i -= %[2]s if %[4]si >= %[1]s(len(_%[1]sIndex)-1) { - return fmt.Sprintf("%[1]s(%%d)", i + %[2]s) + return "%[1]s(" + strconv.FormatInt(int64(i + %[2]s), 10) + ")" } return _%[1]sName[_%[1]sIndex[i] : _%[1]sIndex[i+1]] } @@ -655,7 +629,7 @@ func (g *Generator) buildMultipleRuns(runs [][]Value, typeName string) { typeName, i, typeName, i, typeName, i) } g.Printf("\tdefault:\n") - g.Printf("\t\treturn fmt.Sprintf(\"%s(%%d)\", i)\n", typeName) + g.Printf("\t\treturn \"%s(\" + strconv.FormatInt(int64(i), 10) + \")\"\n", typeName) g.Printf("\t}\n") g.Printf("}\n") } @@ -682,6 +656,6 @@ const stringMap = `func (i %[1]s) String() string { if str, ok := _%[1]sMap[i]; ok { return str } - return fmt.Sprintf("%[1]s(%%d)", i) + return "%[1]s(" + strconv.FormatInt(int64(i), 10) + ")" } `