diff options
Diffstat (limited to 'vendor/github.com/magefile/mage/parse/parse.go')
| -rw-r--r-- | vendor/github.com/magefile/mage/parse/parse.go | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/vendor/github.com/magefile/mage/parse/parse.go b/vendor/github.com/magefile/mage/parse/parse.go new file mode 100644 index 0000000..65f5a34 --- /dev/null +++ b/vendor/github.com/magefile/mage/parse/parse.go @@ -0,0 +1,271 @@ +package parse + +import ( + "fmt" + "go/ast" + "go/build" + "go/doc" + "go/parser" + "go/token" + "go/types" + "log" + "os" + "os/exec" + "strings" + + mgTypes "github.com/magefile/mage/types" +) + +type PkgInfo struct { + Funcs []Function + DefaultIsError bool + DefaultIsContext bool + DefaultName string + DefaultFunc Function +} + +// Function represented a job function from a mage file +type Function struct { + Name string + IsError bool + IsContext bool + Synopsis string + Comment string +} + +// TemplateString returns code for the template switch to run the target. +// It wraps each target call to match the func(context.Context) error that +// runTarget requires. +func (f Function) TemplateString() string { + if f.IsContext && f.IsError { + out := `wrapFn := func(ctx context.Context) error { + return %s(ctx) + } + err := runTarget(wrapFn)` + return fmt.Sprintf(out, f.Name) + } + if f.IsContext && !f.IsError { + out := `wrapFn := func(ctx context.Context) error { + %s(ctx) + return nil + } + err := runTarget(wrapFn)` + return fmt.Sprintf(out, f.Name) + } + if !f.IsContext && f.IsError { + out := `wrapFn := func(ctx context.Context) error { + return %s() + } + err := runTarget(wrapFn)` + return fmt.Sprintf(out, f.Name) + } + if !f.IsContext && !f.IsError { + out := `wrapFn := func(ctx context.Context) error { + %s() + return nil + } + err := runTarget(wrapFn)` + return fmt.Sprintf(out, f.Name) + } + return `fmt.Printf("Error formatting job code\n") + os.Exit(1)` +} + +// Package parses a package +func Package(path string, files []string) (*PkgInfo, error) { + fset := token.NewFileSet() + + pkg, err := getPackage(path, files, fset) + if err != nil { + return nil, err + } + + info, err := makeInfo(path, fset, pkg.Files) + if err != nil { + return nil, err + } + + pi := &PkgInfo{} + + p := doc.New(pkg, "./", 0) + for _, f := range p.Funcs { + if f.Recv != "" { + // skip methods + continue + } + if !ast.IsExported(f.Name) { + // skip non-exported functions + continue + } + if typ := voidOrError(f.Decl.Type, info); typ != mgTypes.InvalidType { + pi.Funcs = append(pi.Funcs, Function{ + Name: f.Name, + Comment: f.Doc, + Synopsis: doc.Synopsis(f.Doc), + IsError: typ == mgTypes.ErrorType || typ == mgTypes.ContextErrorType, + IsContext: typ == mgTypes.ContextVoidType || typ == mgTypes.ContextErrorType, + }) + } + } + + setDefault(p, pi, info) + + return pi, nil +} + +func setDefault(p *doc.Package, pi *PkgInfo, info types.Info) { + for _, v := range p.Vars { + for x, name := range v.Names { + if name != "Default" { + continue + } + spec := v.Decl.Specs[x].(*ast.ValueSpec) + if len(spec.Values) != 1 { + log.Println("warning: default declaration has multiple values") + } + id, ok := spec.Values[0].(*ast.Ident) + if !ok { + log.Println("warning: default declaration is not a function name") + } + for _, f := range pi.Funcs { + if f.Name == id.Name { + pi.DefaultName = f.Name + pi.DefaultIsError = f.IsError + pi.DefaultIsContext = f.IsContext + pi.DefaultFunc = f + return + } + } + log.Println("warning: default declaration does not reference a mage target") + } + } +} + +// getPackage returns the non-test package at the given path. +func getPackage(path string, files []string, fset *token.FileSet) (*ast.Package, error) { + fm := make(map[string]bool, len(files)) + for _, f := range files { + fm[f] = true + } + + filter := func(f os.FileInfo) bool { + return fm[f.Name()] + } + + pkgs, err := parser.ParseDir(fset, path, filter, parser.ParseComments) + if err != nil { + return nil, fmt.Errorf("failed to parse directory: %v", err) + } + + for name, pkg := range pkgs { + if !strings.HasSuffix(name, "_test") { + return pkg, nil + } + } + return nil, fmt.Errorf("no non-test packages found in %s", path) +} + +func makeInfo(dir string, fset *token.FileSet, files map[string]*ast.File) (types.Info, error) { + goroot := os.Getenv("GOROOT") + if goroot == "" { + c := exec.Command("go", "env", "GOROOT") + b, err := c.Output() + if err != nil { + return types.Info{}, fmt.Errorf("failed to get GOROOT from 'go env': %v", err) + } + goroot = strings.TrimSpace(string(b)) + if goroot == "" { + return types.Info{}, fmt.Errorf("could not determine GOROOT") + } + } + + build.Default.GOROOT = goroot + + cfg := types.Config{ + Importer: getImporter(fset), + } + + info := types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + } + + fs := make([]*ast.File, 0, len(files)) + for _, v := range files { + fs = append(fs, v) + } + + _, err := cfg.Check(dir, fset, fs, &info) + if err != nil { + return info, fmt.Errorf("failed to check types in directory: %v", err) + } + return info, nil +} + +// errorOrVoid filters the list of functions to only those that return only an +// error or have no return value, and have no parameters. +func errorOrVoid(fns []*ast.FuncDecl, info types.Info) []*ast.FuncDecl { + fds := []*ast.FuncDecl{} + + for _, fn := range fns { + if voidOrError(fn.Type, info) != mgTypes.InvalidType { + fds = append(fds, fn) + } + } + return fds +} + +func hasContextParam(ft *ast.FuncType, info types.Info) bool { + if ft.Params.NumFields() == 1 { + ret := ft.Params.List[0] + t := info.TypeOf(ret.Type) + if t != nil && t.String() == "context.Context" { + return true + } + } + return false +} + +func hasVoidReturn(ft *ast.FuncType, info types.Info) bool { + res := ft.Results + if res.NumFields() == 0 { + return true + } + return false +} + +func hasErrorReturn(ft *ast.FuncType, info types.Info) bool { + res := ft.Results + if res.NumFields() == 1 { + ret := res.List[0] + if len(ret.Names) > 1 { + return false + } + t := info.TypeOf(ret.Type) + if t != nil && t.String() == "error" { + return true + } + } + return false +} + +func voidOrError(ft *ast.FuncType, info types.Info) mgTypes.FuncType { + if hasContextParam(ft, info) { + if hasVoidReturn(ft, info) { + return mgTypes.ContextVoidType + } + if hasErrorReturn(ft, info) { + return mgTypes.ContextErrorType + } + } + if ft.Params.NumFields() == 0 { + if hasVoidReturn(ft, info) { + return mgTypes.VoidType + } + if hasErrorReturn(ft, info) { + return mgTypes.ErrorType + } + } + return mgTypes.InvalidType +} |
