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Diffstat (limited to 'vendor/github.com/google/wire/wire.go')
| -rw-r--r-- | vendor/github.com/google/wire/wire.go | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/vendor/github.com/google/wire/wire.go b/vendor/github.com/google/wire/wire.go new file mode 100644 index 00000000..941d6c65 --- /dev/null +++ b/vendor/github.com/google/wire/wire.go @@ -0,0 +1,191 @@ +// Copyright 2018 The Wire Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// https://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package wire contains directives for Wire code generation. +// For an overview of working with Wire, see the user guide at +// https://github.com/google/wire/blob/master/docs/guide.md +// +// The directives in this package are used as input to the Wire code generation +// tool. The entry point of Wire's analysis are injector functions: function +// templates denoted by only containing a call to Build. The arguments to Build +// describes a set of providers and the Wire code generation tool builds a +// directed acylic graph of the providers' output types. The generated code will +// fill in the function template by using the providers from the provider set to +// instantiate any needed types. +package wire + +// ProviderSet is a marker type that collects a group of providers. +type ProviderSet struct{} + +// NewSet creates a new provider set that includes the providers in its +// arguments. Each argument is a function value, a provider set, a call to +// Struct, a call to Bind, a call to Value, a call to InterfaceValue or a call +// to FieldsOf. +// +// Passing a function value to NewSet declares that the function's first +// return value type will be provided by calling the function. The arguments +// to the function will come from the providers for their types. As such, all +// the function's parameters must be of non-identical types. The function may +// optionally return an error as its last return value and a cleanup function +// as the second return value. A cleanup function must be of type func() and is +// guaranteed to be called before the cleanup function of any of the +// provider's inputs. If any provider returns an error, the injector function +// will call all the appropriate cleanup functions and return the error from +// the injector function. +// +// Passing a ProviderSet to NewSet is the same as if the set's contents +// were passed as arguments to NewSet directly. +// +// The behavior of passing the result of a call to other functions in this +// package are described in their respective doc comments. +// +// For compatibility with older versions of Wire, passing a struct value of type +// S to NewSet declares that both S and *S will be provided by creating a new +// value of the appropriate type by filling in each field of S using the +// provider of the field's type. This form is deprecated and will be removed in +// a future version of Wire: new providers sets should use wire.Struct. +func NewSet(...interface{}) ProviderSet { + return ProviderSet{} +} + +// Build is placed in the body of an injector function template to declare the +// providers to use. The Wire code generation tool will fill in an +// implementation of the function. The arguments to Build are interpreted the +// same as NewSet: they determine the provider set presented to Wire's +// dependency graph. Build returns an error message that can be sent to a call +// to panic(). +// +// The parameters of the injector function are used as inputs in the dependency +// graph. +// +// Similar to provider functions passed into NewSet, the first return value is +// the output of the injector function, the optional second return value is a +// cleanup function, and the optional last return value is an error. If any of +// the provider functions in the injector function's provider set return errors +// or cleanup functions, the corresponding return value must be present in the +// injector function template. +// +// Examples: +// +// func injector(ctx context.Context) (*sql.DB, error) { +// wire.Build(otherpkg.FooSet, myProviderFunc) +// return nil, nil +// } +// +// func injector(ctx context.Context) (*sql.DB, error) { +// panic(wire.Build(otherpkg.FooSet, myProviderFunc)) +// } +func Build(...interface{}) string { + return "implementation not generated, run wire" +} + +// A Binding maps an interface to a concrete type. +type Binding struct{} + +// Bind declares that a concrete type should be used to satisfy a dependency on +// the type of iface. iface must be a pointer to an interface type, to must be a +// pointer to a concrete type. +// +// Example: +// +// type Fooer interface { +// Foo() +// } +// +// type MyFoo struct{} +// +// func (MyFoo) Foo() {} +// +// var MySet = wire.NewSet( +// wire.Struct(new(MyFoo)) +// wire.Bind(new(Fooer), new(MyFoo))) +func Bind(iface, to interface{}) Binding { + return Binding{} +} + +// bindToUsePointer is detected by the wire tool to indicate that Bind's second argument should take a pointer. +// See https://github.com/google/wire/issues/120 for details. +const bindToUsePointer = true + +// A ProvidedValue is an expression that is copied to the generated injector. +type ProvidedValue struct{} + +// Value binds an expression to provide the type of the expression. +// The expression may not be an interface value; use InterfaceValue for that. +// +// Example: +// +// var MySet = wire.NewSet(wire.Value([]string(nil))) +func Value(interface{}) ProvidedValue { + return ProvidedValue{} +} + +// InterfaceValue binds an expression to provide a specific interface type. +// The first argument is a pointer to the interface which user wants to provide. +// The second argument is the actual variable value whose type implements the +// interface. +// +// Example: +// +// var MySet = wire.NewSet(wire.InterfaceValue(new(io.Reader), os.Stdin)) +func InterfaceValue(typ interface{}, x interface{}) ProvidedValue { + return ProvidedValue{} +} + +// A StructProvider represents a named struct. +type StructProvider struct{} + +// Struct specifies that the given struct type will be provided by filling in the fields in the struct that have the names given. +// +// The first argument must be a pointer to the struct type. For a struct type +// Foo, Wire will use field-filling to provide both Foo and *Foo. The remaining +// arguments are field names to fill in. As a special case, if a single name "*" +// is given, then all of the fields in the struct will be filled in. +// +// For example: +// +// type S struct { +// MyFoo *Foo +// MyBar *Bar +// } +// var Set = wire.NewSet(wire.Struct(new(S), "MyFoo")) -> inject only S.MyFoo +// var Set = wire.NewSet(wire.Struct(new(S), "*")) -> inject all fields +func Struct(structType interface{}, fieldNames ...string) StructProvider { + return StructProvider{} +} + +// StructFields is a collection of the fields from a struct. +type StructFields struct{} + +// FieldsOf declares that the fields named of the given struct type will be used +// to provide the types of those fields. The structType argument must be a +// pointer to the struct or a pointer to a pointer to the struct it wishes to reference. +// +// The following example would provide *Foo and *Bar using S.MyFoo and S.MyBar respectively: +// +// type S struct { +// MyFoo *Foo +// MyBar *Bar +// } +// +// func NewStruct() S { /* ... */ } +// var Set = wire.NewSet(wire.FieldsOf(new(S), "MyFoo", "MyBar")) +// +// or +// +// func NewStruct() *S { /* ... */ } +// var Set = wire.NewSet(wire.FieldsOf(new(*S), "MyFoo", "MyBar")) +func FieldsOf(structType interface{}, fieldNames ...string) StructFields { + return StructFields{} +} |
