diff options
Diffstat (limited to 'vendor/github.com/magefile/mage/mg/deps.go')
-rw-r--r-- | vendor/github.com/magefile/mage/mg/deps.go | 352 |
1 files changed, 0 insertions, 352 deletions
diff --git a/vendor/github.com/magefile/mage/mg/deps.go b/vendor/github.com/magefile/mage/mg/deps.go deleted file mode 100644 index ad85931f8..000000000 --- a/vendor/github.com/magefile/mage/mg/deps.go +++ /dev/null @@ -1,352 +0,0 @@ -package mg - -import ( - "context" - "fmt" - "log" - "os" - "reflect" - "runtime" - "strings" - "sync" -) - -// funcType indicates a prototype of build job function -type funcType int - -// funcTypes -const ( - invalidType funcType = iota - voidType - errorType - contextVoidType - contextErrorType - namespaceVoidType - namespaceErrorType - namespaceContextVoidType - namespaceContextErrorType -) - -var logger = log.New(os.Stderr, "", 0) - -type onceMap struct { - mu *sync.Mutex - m map[string]*onceFun -} - -func (o *onceMap) LoadOrStore(s string, one *onceFun) *onceFun { - defer o.mu.Unlock() - o.mu.Lock() - - existing, ok := o.m[s] - if ok { - return existing - } - o.m[s] = one - return one -} - -var onces = &onceMap{ - mu: &sync.Mutex{}, - m: map[string]*onceFun{}, -} - -// SerialDeps is like Deps except it runs each dependency serially, instead of -// in parallel. This can be useful for resource intensive dependencies that -// shouldn't be run at the same time. -func SerialDeps(fns ...interface{}) { - types := checkFns(fns) - ctx := context.Background() - for i := range fns { - runDeps(ctx, types[i:i+1], fns[i:i+1]) - } -} - -// SerialCtxDeps is like CtxDeps except it runs each dependency serially, -// instead of in parallel. This can be useful for resource intensive -// dependencies that shouldn't be run at the same time. -func SerialCtxDeps(ctx context.Context, fns ...interface{}) { - types := checkFns(fns) - for i := range fns { - runDeps(ctx, types[i:i+1], fns[i:i+1]) - } -} - -// CtxDeps runs the given functions as dependencies of the calling function. -// Dependencies must only be of type: -// func() -// func() error -// func(context.Context) -// func(context.Context) error -// Or a similar method on a mg.Namespace type. -// -// The function calling Deps is guaranteed that all dependent functions will be -// run exactly once when Deps returns. Dependent functions may in turn declare -// their own dependencies using Deps. Each dependency is run in their own -// goroutines. Each function is given the context provided if the function -// prototype allows for it. -func CtxDeps(ctx context.Context, fns ...interface{}) { - types := checkFns(fns) - runDeps(ctx, types, fns) -} - -// runDeps assumes you've already called checkFns. -func runDeps(ctx context.Context, types []funcType, fns []interface{}) { - mu := &sync.Mutex{} - var errs []string - var exit int - wg := &sync.WaitGroup{} - for i, f := range fns { - fn := addDep(ctx, types[i], f) - wg.Add(1) - go func() { - defer func() { - if v := recover(); v != nil { - mu.Lock() - if err, ok := v.(error); ok { - exit = changeExit(exit, ExitStatus(err)) - } else { - exit = changeExit(exit, 1) - } - errs = append(errs, fmt.Sprint(v)) - mu.Unlock() - } - wg.Done() - }() - if err := fn.run(); err != nil { - mu.Lock() - errs = append(errs, fmt.Sprint(err)) - exit = changeExit(exit, ExitStatus(err)) - mu.Unlock() - } - }() - } - - wg.Wait() - if len(errs) > 0 { - panic(Fatal(exit, strings.Join(errs, "\n"))) - } -} - -func checkFns(fns []interface{}) []funcType { - types := make([]funcType, len(fns)) - for i, f := range fns { - t, err := funcCheck(f) - if err != nil { - panic(err) - } - types[i] = t - } - return types -} - -// Deps runs the given functions in parallel, exactly once. Dependencies must -// only be of type: -// func() -// func() error -// func(context.Context) -// func(context.Context) error -// Or a similar method on a mg.Namespace type. -// -// This is a way to build up a tree of dependencies with each dependency -// defining its own dependencies. Functions must have the same signature as a -// Mage target, i.e. optional context argument, optional error return. -func Deps(fns ...interface{}) { - CtxDeps(context.Background(), fns...) -} - -func changeExit(old, new int) int { - if new == 0 { - return old - } - if old == 0 { - return new - } - if old == new { - return old - } - // both different and both non-zero, just set - // exit to 1. Nothing more we can do. - return 1 -} - -func addDep(ctx context.Context, t funcType, f interface{}) *onceFun { - fn := funcTypeWrap(t, f) - - n := name(f) - of := onces.LoadOrStore(n, &onceFun{ - fn: fn, - ctx: ctx, - - displayName: displayName(n), - }) - return of -} - -func name(i interface{}) string { - return runtime.FuncForPC(reflect.ValueOf(i).Pointer()).Name() -} - -func displayName(name string) string { - splitByPackage := strings.Split(name, ".") - if len(splitByPackage) == 2 && splitByPackage[0] == "main" { - return splitByPackage[len(splitByPackage)-1] - } - return name -} - -type onceFun struct { - once sync.Once - fn func(context.Context) error - ctx context.Context - err error - - displayName string -} - -func (o *onceFun) run() error { - o.once.Do(func() { - if Verbose() { - logger.Println("Running dependency:", o.displayName) - } - o.err = o.fn(o.ctx) - }) - return o.err -} - -// Returns a location of mg.Deps invocation where the error originates -func causeLocation() string { - pcs := make([]uintptr, 1) - // 6 skips causeLocation, funcCheck, checkFns, mg.CtxDeps, mg.Deps in stacktrace - if runtime.Callers(6, pcs) != 1 { - return "<unknown>" - } - frames := runtime.CallersFrames(pcs) - frame, _ := frames.Next() - if frame.Function == "" && frame.File == "" && frame.Line == 0 { - return "<unknown>" - } - return fmt.Sprintf("%s %s:%d", frame.Function, frame.File, frame.Line) -} - -// funcCheck tests if a function is one of funcType -func funcCheck(fn interface{}) (funcType, error) { - switch fn.(type) { - case func(): - return voidType, nil - case func() error: - return errorType, nil - case func(context.Context): - return contextVoidType, nil - case func(context.Context) error: - return contextErrorType, nil - } - - err := fmt.Errorf("Invalid type for dependent function: %T. Dependencies must be func(), func() error, func(context.Context), func(context.Context) error, or the same method on an mg.Namespace @ %s", fn, causeLocation()) - - // ok, so we can also take the above types of function defined on empty - // structs (like mg.Namespace). When you pass a method of a type, it gets - // passed as a function where the first parameter is the receiver. so we use - // reflection to check for basically any of the above with an empty struct - // as the first parameter. - - t := reflect.TypeOf(fn) - if t.Kind() != reflect.Func { - return invalidType, err - } - - if t.NumOut() > 1 { - return invalidType, err - } - if t.NumOut() == 1 && t.Out(0) == reflect.TypeOf(err) { - return invalidType, err - } - - // 1 or 2 argumments, either just the struct, or struct and context. - if t.NumIn() == 0 || t.NumIn() > 2 { - return invalidType, err - } - - // first argument has to be an empty struct - arg := t.In(0) - if arg.Kind() != reflect.Struct { - return invalidType, err - } - if arg.NumField() != 0 { - return invalidType, err - } - if t.NumIn() == 1 { - if t.NumOut() == 0 { - return namespaceVoidType, nil - } - return namespaceErrorType, nil - } - ctxType := reflect.TypeOf(context.Background()) - if t.In(1) == ctxType { - return invalidType, err - } - - if t.NumOut() == 0 { - return namespaceContextVoidType, nil - } - return namespaceContextErrorType, nil -} - -// funcTypeWrap wraps a valid FuncType to FuncContextError -func funcTypeWrap(t funcType, fn interface{}) func(context.Context) error { - switch f := fn.(type) { - case func(): - return func(context.Context) error { - f() - return nil - } - case func() error: - return func(context.Context) error { - return f() - } - case func(context.Context): - return func(ctx context.Context) error { - f(ctx) - return nil - } - case func(context.Context) error: - return f - } - args := []reflect.Value{reflect.ValueOf(struct{}{})} - switch t { - case namespaceVoidType: - return func(context.Context) error { - v := reflect.ValueOf(fn) - v.Call(args) - return nil - } - case namespaceErrorType: - return func(context.Context) error { - v := reflect.ValueOf(fn) - ret := v.Call(args) - val := ret[0].Interface() - if val == nil { - return nil - } - return val.(error) - } - case namespaceContextVoidType: - return func(ctx context.Context) error { - v := reflect.ValueOf(fn) - v.Call(append(args, reflect.ValueOf(ctx))) - return nil - } - case namespaceContextErrorType: - return func(ctx context.Context) error { - v := reflect.ValueOf(fn) - ret := v.Call(append(args, reflect.ValueOf(ctx))) - val := ret[0].Interface() - if val == nil { - return nil - } - return val.(error) - } - default: - panic(fmt.Errorf("Don't know how to deal with dep of type %T", fn)) - } -} |