internal/wire: copy over anonymous imports (#101)

Adds Kumbirai Tanekha to A+C.

Fixes #94

AUTHORS

@@ -12,6 +12,7 @@
 
 Google LLC
 ktr <ktr@syfm.me>
+Kumbirai Tanekha <kumbirai.tanekha@gmail.com>
 Oleg Kovalov <iamolegkovalov@gmail.com>
 Yoichiro Shimizu <budougumi0617@gmail.com>
 Zachary Romero <zacromero3@gmail.com>

CONTRIBUTORS

@@ -34,6 +34,7 @@ Christina Austin <4240737+clausti@users.noreply.github.com>
 Eno Compton <enocom@google.com>
 Issac Trotts <issactrotts@google.com> <issac.trotts@gmail.com>
 ktr <ktr@syfm.me>
+Kumbirai Tanekha <kumbirai.tanekha@gmail.com>
 Oleg Kovalov <iamolegkovalov@gmail.com>
 Robert van Gent <rvangent@google.com> <vangent@gmail.com>
 Ross Light <light@google.com> <ross@zombiezen.com>

internal/wire/testdata/PkgImport/anon1/anon1.go

@@ -0,0 +1,15 @@
+// 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 anon1

internal/wire/testdata/PkgImport/anon2/anon2.go

@@ -0,0 +1,15 @@
+// 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 anon2

internal/wire/testdata/PkgImport/foo/wire.go

@@ -17,6 +17,8 @@
 package main
 
 import (
+	_ "example.com/anon1"
+	_ "example.com/anon2"
 	"github.com/google/wire"
 )
 

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

@@ -9,6 +9,11 @@ import (
 	"example.com/bar"
 )
 
+import (
+	_ "example.com/anon1"
+	_ "example.com/anon2"
+)
+
 // Injectors from wire.go:
 
 func injectFooBar() FooBar {

internal/wire/wire.go

@@ -171,6 +171,12 @@ func generateInjectors(g *gen, pkg *packages.Package) (injectorFiles []*ast.File
 				continue
 			}
 		}
+
+		for _, impt := range f.Imports {
+			if impt.Name != nil && impt.Name.Name == "_" {
+				g.anonImports[impt.Path.Value] = true
+			}
+		}
 	}
 	if len(ec.errors) > 0 {
 		return nil, ec.errors
@@ -221,17 +227,19 @@ type importInfo struct {
 
 // gen is the file-wide generator state.
 type gen struct {
-	pkg     *packages.Package
-	buf     bytes.Buffer
-	imports map[string]importInfo
-	values  map[ast.Expr]string
+	pkg         *packages.Package
+	buf         bytes.Buffer
+	imports     map[string]importInfo
+	anonImports map[string]bool
+	values      map[ast.Expr]string
 }
 
 func newGen(pkg *packages.Package) *gen {
 	return &gen{
-		pkg:     pkg,
-		imports: make(map[string]importInfo),
-		values:  make(map[ast.Expr]string),
+		pkg:         pkg,
+		anonImports: make(map[string]bool),
+		imports:     make(map[string]importInfo),
+		values:      make(map[ast.Expr]string),
 	}
 }
 
@@ -265,6 +273,19 @@ func (g *gen) frame() []byte {
 		}
 		buf.WriteString(")\n\n")
 	}
+	if len(g.anonImports) > 0 {
+		buf.WriteString("import (\n")
+		anonImps := make([]string, 0, len(g.anonImports))
+		for path, _ := range g.anonImports {
+			anonImps = append(anonImps, path)
+		}
+		sort.Strings(anonImps)
+
+		for _, path := range anonImps {
+			fmt.Fprintf(&buf, "\t_ %s\n", path)
+		}
+		buf.WriteString(")\n\n")
+	}
 	buf.Write(g.buf.Bytes())
 	return buf.Bytes()
 }