internal/wire: support specifying struct fields to inject (#147)

Added wire.Struct function and deprecate old form.

Updates #36

internal/wire/testdata/ExampleWithMocks/foo/foo.go

@@ -51,8 +51,8 @@ func main() {
 
 // appSet is a provider set for creating a real app.
 var appSet = wire.NewSet(
-	app{},
-	greeter{},
+	wire.Struct(new(app), "*"),
+	wire.Struct(new(greeter), "*"),
 	wire.InterfaceValue(new(timer), realTime{}),
 )
 
@@ -61,17 +61,17 @@ var appSet = wire.NewSet(
 // arguments to the injector.
 // It is used for Approach A.
 var appSetWithoutMocks = wire.NewSet(
-	app{},
-	greeter{},
+	wire.Struct(new(app), "*"),
+	wire.Struct(new(greeter), "*"),
 )
 
 // mockAppSet is a provider set for creating a mocked app, including the mocked
 // dependencies.
 // It is used for Approach B.
 var mockAppSet = wire.NewSet(
-	app{},
-	greeter{},
-	appWithMocks{},
+	wire.Struct(new(app), "*"),
+	wire.Struct(new(greeter), "*"),
+	wire.Struct(new(appWithMocks), "*"),
 	// For each mocked dependency, add a provider and use wire.Bind to bind
 	// the concrete type to the relevant interface.
 	newMockTimer,

internal/wire/testdata/FieldsOfImportedStruct/main/wire.go

@@ -27,7 +27,7 @@ import (
 
 func newBazService(*baz.Config) *baz.Service {
 	wire.Build(
-		baz.Service{},
+		wire.Struct(new(baz.Service), "*"),
 		wire.FieldsOf(
 			new(*baz.Config),
 			"Foo",

internal/wire/testdata/FieldsOfValueStruct/main/wire.go

@@ -27,7 +27,7 @@ import (
 
 func newBazService() *baz.Service {
 	wire.Build(
-		baz.Service{},
+		wire.Struct(new(baz.Service), "*"),
 		wire.Value(&baz.Config{
 			Foo: &foo.Config{1},
 			Bar: &bar.Config{2},

internal/wire/testdata/MultipleSimilarPackages/main/wire.go

@@ -43,7 +43,7 @@ func (m *MainService) String() string {
 
 func newMainService(MainConfig) *MainService {
 	wire.Build(
-		MainService{},
+		wire.Struct(new(MainService), "Foo", "Bar", "baz"),
 		wire.FieldsOf(
 			new(MainConfig),
 			"Foo",

internal/wire/testdata/Struct/foo/foo.go

@@ -22,7 +22,9 @@ import (
 
 func main() {
 	fb := injectFooBar()
+	pfb := injectPartFooBar()
 	fmt.Println(fb.Foo, fb.Bar)
+	fmt.Println(pfb.Foo, pfb.Bar)
 }
 
 type Foo int
@@ -42,6 +44,11 @@ func provideBar() Bar {
 }
 
 var Set = wire.NewSet(
-	FooBar{},
+	wire.Struct(new(FooBar), "*"),
 	provideFoo,
 	provideBar)
+
+var PartSet = wire.NewSet(
+	wire.Struct(new(FooBar), "Foo"),
+	provideFoo,
+)

internal/wire/testdata/Struct/foo/wire.go

@@ -24,3 +24,8 @@ func injectFooBar() FooBar {
 	wire.Build(Set)
 	return FooBar{}
 }
+
+func injectPartFooBar() FooBar {
+	wire.Build(PartSet)
+	return FooBar{}
+}

internal/wire/testdata/Struct/want/program_out.txt

@@ -1 +1,2 @@
 41 1
+41 0

internal/wire/testdata/Struct/want/wire_gen.go

@@ -16,3 +16,11 @@ func injectFooBar() FooBar {
 	}
 	return fooBar
 }
+
+func injectPartFooBar() FooBar {
+	foo := provideFoo()
+	fooBar := FooBar{
+		Foo: foo,
+	}
+	return fooBar
+}

internal/wire/testdata/StructPointer/foo/foo.go

@@ -45,6 +45,6 @@ func provideBar() Bar {
 }
 
 var Set = wire.NewSet(
-	FooBar{},
+	wire.Struct(new(FooBar), "*"),
 	provideFoo,
 	provideBar)

internal/wire/testdata/StructPointer/foo/wire.go

@@ -26,6 +26,6 @@ func injectFooBar() *FooBar {
 }
 
 func injectEmptyStruct() *Empty {
-	wire.Build(Empty{})
+	wire.Build(wire.Struct(new(Empty)))
 	return nil
 }