Convert go_generics tests to starlark.

For some reason these tests were broken when run via the bazel docker
container. The mechanism used was a bit crazy (self-extracting bundle),
so convert them to use straight-forward starlark rules. This has the
added advantaged that they are now independent tests.

24 files changed, 1183 insertions, 0 deletions

diff --git a/tools/go_generics/tests/BUILD b/tools/go_generics/tests/BUILD
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/tools/go_generics/tests/BUILD
diff --git a/tools/go_generics/tests/all_stmts/BUILD b/tools/go_generics/tests/all_stmts/BUILD
new file mode 100644
index 000000000..fbc07dbff
--- /dev/null
+++ b/tools/go_generics/tests/all_stmts/BUILD
@@ -0,0 +1,10 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "all_stmts",
+    inputs = ["input.go"],
+    output = "output.go",
+    types = {
+        "T": "Q",
+    },
+)
diff --git a/tools/go_generics/tests/all_stmts/input.go b/tools/go_generics/tests/all_stmts/input.go
new file mode 100644
index 000000000..4791d1ff1
--- /dev/null
+++ b/tools/go_generics/tests/all_stmts/input.go
@@ -0,0 +1,290 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+import (
+	"sync"
+)
+
+type T int
+
+func h(T) {
+}
+
+type s struct {
+	a, b int
+	c    []int
+}
+
+func g(T) *s {
+	return &s{}
+}
+
+func f() (T, []int) {
+	// Branch.
+	goto T
+	goto R
+
+	// Labeled.
+T:
+	_ = T(0)
+
+	// Empty.
+R:
+	;
+
+	// Assignment with definition.
+	a, b, c := T(1), T(2), T(3)
+	_, _, _ = a, b, c
+
+	// Assignment without definition.
+	g(T(0)).a, g(T(1)).b, c = int(T(1)), int(T(2)), T(3)
+	_, _, _ = a, b, c
+
+	// Block.
+	{
+		var T T
+		T = 0
+		_ = T
+	}
+
+	// Declarations.
+	type Type T
+	const Const T = 10
+	var g1 func(T, int, ...T) (int, T)
+	var v T
+	var w = T(0)
+	{
+		var T struct {
+			f []T
+		}
+		_ = T
+	}
+
+	// Defer.
+	defer g1(T(0), 1)
+
+	// Expression.
+	h(v + w + T(1))
+
+	// For statements.
+	for i := T(0); i < T(10); i++ {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	}
+
+	for {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	}
+
+	// Go.
+	go g1(T(0), 1)
+
+	// If statements.
+	if a != T(1) {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	}
+
+	if a := T(0); a != T(1) {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	}
+
+	if a := T(0); a != T(1) {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	} else if b := T(0); b != T(1) {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	} else if T := T(0); T != 1 {
+		T++
+	} else {
+		T--
+	}
+
+	if a := T(0); a != T(1) {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	} else {
+		var T func(int) T
+		v := T(0)
+		_ = v
+	}
+
+	// Inc/Dec statements.
+	(*(*T)(nil))++
+	(*(*T)(nil))--
+
+	// Range statements.
+	for g(T(0)).a, g(T(1)).b = range g(T(10)).c {
+		var d T
+		_ = d
+	}
+
+	for T, b := range g(T(10)).c {
+		_ = T
+		_ = b
+	}
+
+	// Select statement.
+	{
+		var fch func(T) chan int
+
+		select {
+		case <-fch(T(30)):
+			var T T
+			T = 0
+			_ = T
+		default:
+			var T T
+			T = 0
+			_ = T
+		case T := <-fch(T(30)):
+			T = 0
+			_ = T
+		case g(T(0)).a = <-fch(T(30)):
+			var T T
+			T = 0
+			_ = T
+		case fch(T(30)) <- int(T(0)):
+			var T T
+			T = 0
+			_ = T
+		}
+	}
+
+	// Send statements.
+	{
+		var ch chan T
+		var fch func(T) chan int
+
+		ch <- T(0)
+		fch(T(1)) <- g(T(10)).a
+	}
+
+	// Switch statements.
+	{
+		var a T
+		var b int
+		switch {
+		case a == T(0):
+			var T T
+			T = 0
+			_ = T
+		case a < T(0), b < g(T(10)).a:
+			var T T
+			T = 0
+			_ = T
+		default:
+			var T T
+			T = 0
+			_ = T
+		}
+	}
+
+	switch T(g(T(10)).a) {
+	case T(0):
+		var T T
+		T = 0
+		_ = T
+	case T(1), T(g(T(10)).a):
+		var T T
+		T = 0
+		_ = T
+	default:
+		var T T
+		T = 0
+		_ = T
+	}
+
+	switch b := g(T(10)); T(b.a) + T(10) {
+	case T(0):
+		var T T
+		T = 0
+		_ = T
+	case T(1), T(g(T(10)).a):
+		var T T
+		T = 0
+		_ = T
+	default:
+		var T T
+		T = 0
+		_ = T
+	}
+
+	// Type switch statements.
+	{
+		var interfaceFunc func(T) interface{}
+
+		switch interfaceFunc(T(0)).(type) {
+		case *T, T, int:
+			var T T
+			T = 0
+			_ = T
+		case sync.Mutex, **T:
+			var T T
+			T = 0
+			_ = T
+		default:
+			var T T
+			T = 0
+			_ = T
+		}
+
+		switch x := interfaceFunc(T(0)).(type) {
+		case *T, T, int:
+			var T T
+			T = 0
+			_ = T
+			_ = x
+		case sync.Mutex, **T:
+			var T T
+			T = 0
+			_ = T
+		default:
+			var T T
+			T = 0
+			_ = T
+		}
+
+		switch t := T(0); x := interfaceFunc(T(0) + t).(type) {
+		case *T, T, int:
+			var T T
+			T = 0
+			_ = T
+			_ = x
+		case sync.Mutex, **T:
+			var T T
+			T = 0
+			_ = T
+		default:
+			var T T
+			T = 0
+			_ = T
+		}
+	}
+
+	// Return statement.
+	return T(10), g(T(11)).c
+}
diff --git a/tools/go_generics/tests/all_stmts/output.go b/tools/go_generics/tests/all_stmts/output.go
new file mode 100644
index 000000000..a53d84535
--- /dev/null
+++ b/tools/go_generics/tests/all_stmts/output.go
@@ -0,0 +1,288 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+import (
+	"sync"
+)
+
+func h(Q) {
+}
+
+type s struct {
+	a, b int
+	c    []int
+}
+
+func g(Q) *s {
+	return &s{}
+}
+
+func f() (Q, []int) {
+	// Branch.
+	goto T
+	goto R
+
+	// Labeled.
+T:
+	_ = Q(0)
+
+	// Empty.
+R:
+	;
+
+	// Assignment with definition.
+	a, b, c := Q(1), Q(2), Q(3)
+	_, _, _ = a, b, c
+
+	// Assignment without definition.
+	g(Q(0)).a, g(Q(1)).b, c = int(Q(1)), int(Q(2)), Q(3)
+	_, _, _ = a, b, c
+
+	// Block.
+	{
+		var T Q
+		T = 0
+		_ = T
+	}
+
+	// Declarations.
+	type Type Q
+	const Const Q = 10
+	var g1 func(Q, int, ...Q) (int, Q)
+	var v Q
+	var w = Q(0)
+	{
+		var T struct {
+			f []Q
+		}
+		_ = T
+	}
+
+	// Defer.
+	defer g1(Q(0), 1)
+
+	// Expression.
+	h(v + w + Q(1))
+
+	// For statements.
+	for i := Q(0); i < Q(10); i++ {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	}
+
+	for {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	}
+
+	// Go.
+	go g1(Q(0), 1)
+
+	// If statements.
+	if a != Q(1) {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	}
+
+	if a := Q(0); a != Q(1) {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	}
+
+	if a := Q(0); a != Q(1) {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	} else if b := Q(0); b != Q(1) {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	} else if T := Q(0); T != 1 {
+		T++
+	} else {
+		T--
+	}
+
+	if a := Q(0); a != Q(1) {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	} else {
+		var T func(int) Q
+		v := T(0)
+		_ = v
+	}
+
+	// Inc/Dec statements.
+	(*(*Q)(nil))++
+	(*(*Q)(nil))--
+
+	// Range statements.
+	for g(Q(0)).a, g(Q(1)).b = range g(Q(10)).c {
+		var d Q
+		_ = d
+	}
+
+	for T, b := range g(Q(10)).c {
+		_ = T
+		_ = b
+	}
+
+	// Select statement.
+	{
+		var fch func(Q) chan int
+
+		select {
+		case <-fch(Q(30)):
+			var T Q
+			T = 0
+			_ = T
+		default:
+			var T Q
+			T = 0
+			_ = T
+		case T := <-fch(Q(30)):
+			T = 0
+			_ = T
+		case g(Q(0)).a = <-fch(Q(30)):
+			var T Q
+			T = 0
+			_ = T
+		case fch(Q(30)) <- int(Q(0)):
+			var T Q
+			T = 0
+			_ = T
+		}
+	}
+
+	// Send statements.
+	{
+		var ch chan Q
+		var fch func(Q) chan int
+
+		ch <- Q(0)
+		fch(Q(1)) <- g(Q(10)).a
+	}
+
+	// Switch statements.
+	{
+		var a Q
+		var b int
+		switch {
+		case a == Q(0):
+			var T Q
+			T = 0
+			_ = T
+		case a < Q(0), b < g(Q(10)).a:
+			var T Q
+			T = 0
+			_ = T
+		default:
+			var T Q
+			T = 0
+			_ = T
+		}
+	}
+
+	switch Q(g(Q(10)).a) {
+	case Q(0):
+		var T Q
+		T = 0
+		_ = T
+	case Q(1), Q(g(Q(10)).a):
+		var T Q
+		T = 0
+		_ = T
+	default:
+		var T Q
+		T = 0
+		_ = T
+	}
+
+	switch b := g(Q(10)); Q(b.a) + Q(10) {
+	case Q(0):
+		var T Q
+		T = 0
+		_ = T
+	case Q(1), Q(g(Q(10)).a):
+		var T Q
+		T = 0
+		_ = T
+	default:
+		var T Q
+		T = 0
+		_ = T
+	}
+
+	// Type switch statements.
+	{
+		var interfaceFunc func(Q) interface{}
+
+		switch interfaceFunc(Q(0)).(type) {
+		case *Q, Q, int:
+			var T Q
+			T = 0
+			_ = T
+		case sync.Mutex, **Q:
+			var T Q
+			T = 0
+			_ = T
+		default:
+			var T Q
+			T = 0
+			_ = T
+		}
+
+		switch x := interfaceFunc(Q(0)).(type) {
+		case *Q, Q, int:
+			var T Q
+			T = 0
+			_ = T
+			_ = x
+		case sync.Mutex, **Q:
+			var T Q
+			T = 0
+			_ = T
+		default:
+			var T Q
+			T = 0
+			_ = T
+		}
+
+		switch t := Q(0); x := interfaceFunc(Q(0) + t).(type) {
+		case *Q, Q, int:
+			var T Q
+			T = 0
+			_ = T
+			_ = x
+		case sync.Mutex, **Q:
+			var T Q
+			T = 0
+			_ = T
+		default:
+			var T Q
+			T = 0
+			_ = T
+		}
+	}
+
+	// Return statement.
+	return Q(10), g(Q(11)).c
+}
diff --git a/tools/go_generics/tests/all_types/BUILD b/tools/go_generics/tests/all_types/BUILD
new file mode 100644
index 000000000..9144b0811
--- /dev/null
+++ b/tools/go_generics/tests/all_types/BUILD
@@ -0,0 +1,10 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "all_types",
+    inputs = ["input.go"],
+    output = "output.go",
+    types = {
+        "T": "Q",
+    },
+)
diff --git a/tools/go_generics/tests/all_types/input.go b/tools/go_generics/tests/all_types/input.go
new file mode 100644
index 000000000..6f85bbb69
--- /dev/null
+++ b/tools/go_generics/tests/all_types/input.go
@@ -0,0 +1,45 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+import (
+	"./lib"
+)
+
+type T int
+
+type newType struct {
+	a T
+	b lib.T
+	c *T
+	d (T)
+	e chan T
+	f <-chan T
+	g chan<- T
+	h []T
+	i [10]T
+	j map[T]T
+	k func(T, T) (T, T)
+	l interface {
+		f(T)
+	}
+	m struct {
+		T
+		a T
+	}
+}
+
+func f(...T) {
+}
diff --git a/tools/go_generics/tests/all_types/lib/lib.go b/tools/go_generics/tests/all_types/lib/lib.go
new file mode 100644
index 000000000..988786496
--- /dev/null
+++ b/tools/go_generics/tests/all_types/lib/lib.go
@@ -0,0 +1,17 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 lib
+
+type T int32
diff --git a/tools/go_generics/tests/all_types/output.go b/tools/go_generics/tests/all_types/output.go
new file mode 100644
index 000000000..c0bbebfe7
--- /dev/null
+++ b/tools/go_generics/tests/all_types/output.go
@@ -0,0 +1,43 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+import (
+	"./lib"
+)
+
+type newType struct {
+	a Q
+	b lib.T
+	c *Q
+	d (Q)
+	e chan Q
+	f <-chan Q
+	g chan<- Q
+	h []Q
+	i [10]Q
+	j map[Q]Q
+	k func(Q, Q) (Q, Q)
+	l interface {
+		f(Q)
+	}
+	m struct {
+		Q
+		a Q
+	}
+}
+
+func f(...Q) {
+}
diff --git a/tools/go_generics/tests/anon/BUILD b/tools/go_generics/tests/anon/BUILD
new file mode 100644
index 000000000..1890f2817
--- /dev/null
+++ b/tools/go_generics/tests/anon/BUILD
@@ -0,0 +1,12 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "anon",
+    anon = True,
+    inputs = ["input.go"],
+    output = "output.go",
+    suffix = "New",
+    types = {
+        "T": "Q",
+    },
+)
diff --git a/tools/go_generics/tests/anon/input.go b/tools/go_generics/tests/anon/input.go
new file mode 100644
index 000000000..44086d522
--- /dev/null
+++ b/tools/go_generics/tests/anon/input.go
@@ -0,0 +1,46 @@
+// Copyright 2019 The gVisor 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
+//
+//     http://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 tests
+
+type T interface {
+	Apply(T) T
+}
+
+type Foo struct {
+	T
+	Bar map[string]T `json:"bar,omitempty"`
+}
+
+type Baz struct {
+	T someTypeNotT
+}
+
+func (f Foo) GetBar(name string) T {
+	b, ok := f.Bar[name]
+	if ok {
+		b = f.Apply(b)
+	} else {
+		b = f.T
+	}
+	return b
+}
+
+func foobar() {
+	a := Baz{}
+	a.T = 0 // should not be renamed, this is a limitation
+
+	b := otherpkg.UnrelatedType{}
+	b.T = 0 // should not be renamed, this is a limitation
+}
diff --git a/tools/go_generics/tests/anon/output.go b/tools/go_generics/tests/anon/output.go
new file mode 100644
index 000000000..7fa791853
--- /dev/null
+++ b/tools/go_generics/tests/anon/output.go
@@ -0,0 +1,42 @@
+// Copyright 2019 The gVisor 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
+//
+//     http://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 main
+
+type FooNew struct {
+	Q
+	Bar map[string]Q `json:"bar,omitempty"`
+}
+
+type BazNew struct {
+	T someTypeNotT
+}
+
+func (f FooNew) GetBar(name string) Q {
+	b, ok := f.Bar[name]
+	if ok {
+		b = f.Apply(b)
+	} else {
+		b = f.Q
+	}
+	return b
+}
+
+func foobarNew() {
+	a := BazNew{}
+	a.Q = 0
+
+	b := otherpkg.UnrelatedType{}
+	b.Q = 0
+}
diff --git a/tools/go_generics/tests/consts/BUILD b/tools/go_generics/tests/consts/BUILD
new file mode 100644
index 000000000..1e3574593
--- /dev/null
+++ b/tools/go_generics/tests/consts/BUILD
@@ -0,0 +1,17 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "consts",
+    consts = {
+        "c1": "20",
+        "z": "600",
+        "v": "3.3",
+        "s": "\"def\"",
+        "A": "20",
+        "C": "100",
+        "S": "\"def\"",
+        "T": "\"ABC\"",
+    },
+    inputs = ["input.go"],
+    output = "output.go",
+)
diff --git a/tools/go_generics/tests/consts/input.go b/tools/go_generics/tests/consts/input.go
new file mode 100644
index 000000000..04b95fcc6
--- /dev/null
+++ b/tools/go_generics/tests/consts/input.go
@@ -0,0 +1,26 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+const c1 = 10
+const x, y, z = 100, 200, 300
+const v float32 = 1.0 + 2.0
+const s = "abc"
+const (
+	A              = 10
+	B, C, D        = 10, 20, 30
+	S              = "abc"
+	T, U, V string = "abc", "def", "ghi"
+)
diff --git a/tools/go_generics/tests/consts/output.go b/tools/go_generics/tests/consts/output.go
new file mode 100644
index 000000000..18d316cc9
--- /dev/null
+++ b/tools/go_generics/tests/consts/output.go
@@ -0,0 +1,26 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+const c1 = 20
+const x, y, z = 100, 200, 600
+const v float32 = 3.3
+const s = "def"
+const (
+	A              = 20
+	B, C, D        = 10, 100, 30
+	S              = "def"
+	T, U, V string = "ABC", "def", "ghi"
+)
diff --git a/tools/go_generics/tests/defs.bzl b/tools/go_generics/tests/defs.bzl
new file mode 100644
index 000000000..038629852
--- /dev/null
+++ b/tools/go_generics/tests/defs.bzl
@@ -0,0 +1,67 @@
+"""Generics tests."""
+
+load("//tools/go_generics:defs.bzl", "go_template", "go_template_instance")
+
+def _go_generics_test_impl(ctx):
+    runner = ctx.actions.declare_file(ctx.label.name)
+    runner_content = "\n".join([
+        "#!/bin/bash",
+        "exec diff --ignore-blank-lines --ignore-matching-lines=^[[:space:]]*// %s %s" % (
+            ctx.files.template_output[0].short_path,
+            ctx.files.expected_output[0].short_path,
+        ),
+        "",
+    ])
+    ctx.actions.write(runner, runner_content, is_executable = True)
+    return [DefaultInfo(
+        executable = runner,
+        runfiles = ctx.runfiles(
+            files = ctx.files.template_output + ctx.files.expected_output,
+            collect_default = True,
+            collect_data = True,
+        ),
+    )]
+
+_go_generics_test = rule(
+    implementation = _go_generics_test_impl,
+    attrs = {
+        "template_output": attr.label(mandatory = True, allow_single_file = True),
+        "expected_output": attr.label(mandatory = True, allow_single_file = True),
+    },
+    test = True,
+)
+
+"""
+Instantiates a generics test.
+
+Args:
+  name: the name of the test.
+  inputs: all the input files.
+  output: the output files.
+  opts: the template options.
+"""
+
+def go_generics_test(name, inputs, output, types = None, consts = None, **kwargs):
+    if types == None:
+        types = dict()
+    if consts == None:
+        consts = dict()
+    go_template(
+        name = name + "_template",
+        srcs = inputs,
+        types = types.keys(),
+        consts = consts.keys(),
+    )
+    go_template_instance(
+        name = name + "_output",
+        template = ":" + name + "_template",
+        out = name + "_output.go",
+        types = types,
+        consts = consts,
+        **kwargs
+    )
+    _go_generics_test(
+        name = name + "_test",
+        template_output = name + "_output.go",
+        expected_output = output,
+    )
diff --git a/tools/go_generics/tests/imports/BUILD b/tools/go_generics/tests/imports/BUILD
new file mode 100644
index 000000000..c4424ee9c
--- /dev/null
+++ b/tools/go_generics/tests/imports/BUILD
@@ -0,0 +1,18 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "imports",
+    consts = {
+        "n": "math.Uint32",
+        "m": "math.Uint64",
+    },
+    imports = {
+        "sync": "sync",
+        "math": "mymathpath",
+    },
+    inputs = ["input.go"],
+    output = "output.go",
+    types = {
+        "T": "sync.Mutex",
+    },
+)
diff --git a/tools/go_generics/tests/imports/input.go b/tools/go_generics/tests/imports/input.go
new file mode 100644
index 000000000..0f032c2a1
--- /dev/null
+++ b/tools/go_generics/tests/imports/input.go
@@ -0,0 +1,24 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+type T int
+
+var global T
+
+const (
+	m = 0
+	n = 0
+)
diff --git a/tools/go_generics/tests/imports/output.go b/tools/go_generics/tests/imports/output.go
new file mode 100644
index 000000000..2488ca58c
--- /dev/null
+++ b/tools/go_generics/tests/imports/output.go
@@ -0,0 +1,27 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+import (
+	__generics_imported1 "mymathpath"
+	__generics_imported0 "sync"
+)
+
+var global __generics_imported0.Mutex
+
+const (
+	m = __generics_imported1.Uint64
+	n = __generics_imported1.Uint32
+)
diff --git a/tools/go_generics/tests/remove_typedef/BUILD b/tools/go_generics/tests/remove_typedef/BUILD
new file mode 100644
index 000000000..84f6ac1ab
--- /dev/null
+++ b/tools/go_generics/tests/remove_typedef/BUILD
@@ -0,0 +1,10 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "remove_typedef",
+    inputs = ["input.go"],
+    output = "output.go",
+    types = {
+        "T": "U",
+    },
+)
diff --git a/tools/go_generics/tests/remove_typedef/input.go b/tools/go_generics/tests/remove_typedef/input.go
new file mode 100644
index 000000000..cf632bae7
--- /dev/null
+++ b/tools/go_generics/tests/remove_typedef/input.go
@@ -0,0 +1,37 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+func f(T) Q {
+	return Q{}
+}
+
+type T struct{}
+
+type Q struct{}
+
+func (*T) f() {
+}
+
+func (T) g() {
+}
+
+func (*Q) f(T) T {
+	return T{}
+}
+
+func (*Q) g(T) *T {
+	return nil
+}
diff --git a/tools/go_generics/tests/remove_typedef/output.go b/tools/go_generics/tests/remove_typedef/output.go
new file mode 100644
index 000000000..d44fd8e1c
--- /dev/null
+++ b/tools/go_generics/tests/remove_typedef/output.go
@@ -0,0 +1,29 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+func f(U) Q {
+	return Q{}
+}
+
+type Q struct{}
+
+func (*Q) f(U) U {
+	return U{}
+}
+
+func (*Q) g(U) *U {
+	return nil
+}
diff --git a/tools/go_generics/tests/simple/BUILD b/tools/go_generics/tests/simple/BUILD
new file mode 100644
index 000000000..204952b90
--- /dev/null
+++ b/tools/go_generics/tests/simple/BUILD
@@ -0,0 +1,11 @@
+load("//tools/go_generics/tests:defs.bzl", "go_generics_test")
+
+go_generics_test(
+    name = "simple",
+    inputs = ["input.go"],
+    output = "output.go",
+    suffix = "New",
+    types = {
+        "T": "Q",
+    },
+)
diff --git a/tools/go_generics/tests/simple/input.go b/tools/go_generics/tests/simple/input.go
new file mode 100644
index 000000000..2a917f16c
--- /dev/null
+++ b/tools/go_generics/tests/simple/input.go
@@ -0,0 +1,45 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 tests
+
+type T int
+
+var global T
+
+func f(_ T, a int) {
+}
+
+func g(a T, b int) {
+	var c T
+	_ = c
+
+	d := (*T)(nil)
+	_ = d
+}
+
+type R struct {
+	T
+	a *T
+}
+
+var (
+	Z *T = (*T)(nil)
+)
+
+const (
+	X T = (T)(0)
+)
+
+type Y T
diff --git a/tools/go_generics/tests/simple/output.go b/tools/go_generics/tests/simple/output.go
new file mode 100644
index 000000000..6bfa0b25b
--- /dev/null
+++ b/tools/go_generics/tests/simple/output.go
@@ -0,0 +1,43 @@
+// Copyright 2018 The gVisor 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
+//
+//     http://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 main
+
+var globalNew Q
+
+func fNew(_ Q, a int) {
+}
+
+func gNew(a Q, b int) {
+	var c Q
+	_ = c
+
+	d := (*Q)(nil)
+	_ = d
+}
+
+type RNew struct {
+	Q
+	a *Q
+}
+
+var (
+	ZNew *Q = (*Q)(nil)
+)
+
+const (
+	XNew Q = (Q)(0)
+)
+
+type YNew Q