35 files changed, 265 insertions, 133 deletions
diff --git a/tools/bazel.mk b/tools/bazel.mk
index e27e907ab..54844ebbc 100644
--- a/tools/bazel.mk
+++ b/tools/bazel.mk
@@ -15,6 +15,7 @@
 # limitations under the License.
 
 # See base Makefile.
+SHELL=/bin/bash -o pipefail
 BRANCH_NAME := $(shell (git branch --show-current 2>/dev/null || \
 			git rev-parse --abbrev-ref HEAD 2>/dev/null) | \
 			xargs -n 1 basename 2>/dev/null)
@@ -22,8 +23,11 @@ BRANCH_NAME := $(shell (git branch --show-current 2>/dev/null || \
 # Bazel container configuration (see below).
 USER ?= gvisor
 HASH ?= $(shell readlink -m $(CURDIR) | md5sum | cut -c1-8)
+BUILDER_BASE := gvisor.dev/images/default
+BUILDER_IMAGE := gvisor.dev/images/builder
+BUILDER_NAME ?= gvisor-builder-$(HASH)
 DOCKER_NAME ?= gvisor-bazel-$(HASH)
-DOCKER_PRIVILEGED ?= --privileged --network host
+DOCKER_PRIVILEGED ?= --privileged
 BAZEL_CACHE := $(shell readlink -m ~/.cache/bazel/)
 GCLOUD_CONFIG := $(shell readlink -m ~/.config/gcloud/)
 DOCKER_SOCKET := /var/run/docker.sock
@@ -32,17 +36,25 @@ DOCKER_SOCKET := /var/run/docker.sock
 OPTIONS += --test_output=errors --keep_going --verbose_failures=true
 BAZEL := bazel $(STARTUP_OPTIONS)
 
-# Non-configurable.
+# Basic options.
 UID := $(shell id -u ${USER})
 GID := $(shell id -g ${USER})
 USERADD_OPTIONS :=
 FULL_DOCKER_RUN_OPTIONS := $(DOCKER_RUN_OPTIONS)
+FULL_DOCKER_RUN_OPTIONS += --user $(UID):$(GID)
+FULL_DOCKER_RUN_OPTIONS += --entrypoint ""
+FULL_DOCKER_RUN_OPTIONS += --init
 FULL_DOCKER_RUN_OPTIONS += -v "$(BAZEL_CACHE):$(BAZEL_CACHE)"
 FULL_DOCKER_RUN_OPTIONS += -v "$(GCLOUD_CONFIG):$(GCLOUD_CONFIG)"
 FULL_DOCKER_RUN_OPTIONS += -v "/tmp:/tmp"
+FULL_DOCKER_EXEC_OPTIONS := --user $(UID):$(GID)
+FULL_DOCKER_EXEC_OPTIONS += -i
+
+# Add docker passthrough options.
 ifneq ($(DOCKER_PRIVILEGED),)
 FULL_DOCKER_RUN_OPTIONS += -v "$(DOCKER_SOCKET):$(DOCKER_SOCKET)"
 FULL_DOCKER_RUN_OPTIONS += $(DOCKER_PRIVILEGED)
+FULL_DOCKER_EXEC_OPTIONS += $(DOCKER_PRIVILEGED)
 DOCKER_GROUP := $(shell stat -c '%g' $(DOCKER_SOCKET))
 ifneq ($(GID),$(DOCKER_GROUP))
 USERADD_OPTIONS += --groups $(DOCKER_GROUP)
@@ -50,7 +62,30 @@ GROUPADD_DOCKER += groupadd --gid $(DOCKER_GROUP) --non-unique docker-$(HASH) &&
 FULL_DOCKER_RUN_OPTIONS += --group-add $(DOCKER_GROUP)
 endif
 endif
-SHELL=/bin/bash -o pipefail
+
+# Add KVM passthrough options.
+ifneq (,$(wildcard /dev/kvm))
+FULL_DOCKER_RUN_OPTIONS += --device=/dev/kvm
+KVM_GROUP := $(shell stat -c '%g' /dev/kvm)
+ifneq ($(GID),$(KVM_GROUP))
+USERADD_OPTIONS += --groups $(KVM_GROUP)
+GROUPADD_DOCKER += groupadd --gid $(KVM_GROUP) --non-unique kvm-$(HASH) &&
+FULL_DOCKER_RUN_OPTIONS += --group-add $(KVM_GROUP)
+endif
+endif
+
+bazel-image: load-default
+	@if docker ps --all | grep $(BUILDER_NAME); then docker rm -f $(BUILDER_NAME); fi
+	docker run --user 0:0 --entrypoint "" --name $(BUILDER_NAME) \
+		$(BUILDER_BASE) \
+		sh -c "groupadd --gid $(GID) --non-unique $(USER) && \
+		       $(GROUPADD_DOCKER) \
+		       useradd --uid $(UID) --non-unique --no-create-home \
+		               --gid $(GID) $(USERADD_OPTIONS) -d $(HOME) $(USER) && \
+		       if [[ -e /dev/kvm ]]; then chmod a+rw /dev/kvm; fi"
+	docker commit $(BUILDER_NAME) $(BUILDER_IMAGE)
+	@docker rm -f $(BUILDER_NAME)
+.PHONY: bazel-image
 
 ##
 ## Bazel helpers.
@@ -65,41 +100,37 @@ SHELL=/bin/bash -o pipefail
 ##     GCLOUD_CONFIG      - The gcloud config directory (detect: detected).
 ##     DOCKER_SOCKET      - The Docker socket (default: detected).
 ##
-bazel-server-start: load-default ## Starts the bazel server.
+bazel-server-start: bazel-image ## Starts the bazel server.
 	@mkdir -p $(BAZEL_CACHE)
 	@mkdir -p $(GCLOUD_CONFIG)
 	@if docker ps --all | grep $(DOCKER_NAME); then docker rm -f $(DOCKER_NAME); fi
-	docker run -d --rm \
-		--init \
-	        --name $(DOCKER_NAME) \
-		--user 0:0 $(DOCKER_GROUP_OPTIONS) \
+	# This command runs a bazel server, and the container sticks around
+	# until the bazel server exits. This should ensure that it does not
+	# exit in the middle of running a build, but also it won't stick around
+	# forever. The build commands wrap around an appropriate exec into the
+	# container in order to perform work via the bazel client.
+	docker run -d --rm --name $(DOCKER_NAME) \
 		-v "$(CURDIR):$(CURDIR)" \
 		--workdir "$(CURDIR)" \
-		--entrypoint "" \
 		$(FULL_DOCKER_RUN_OPTIONS) \
-		gvisor.dev/images/default \
-		sh -c "groupadd --gid $(GID) --non-unique $(USER) && \
-		       $(GROUPADD_DOCKER) \
-		       useradd --uid $(UID) --non-unique --no-create-home --gid $(GID) $(USERADD_OPTIONS) -d $(HOME) $(USER) && \
-	               $(BAZEL) version && \
-		       exec tail --pid=\$$($(BAZEL) info server_pid) -f /dev/null"
-	@while :; do if docker logs $(DOCKER_NAME) 2>/dev/null | grep "Build label:" >/dev/null; then break; fi; \
-		if ! docker ps | grep $(DOCKER_NAME); then docker logs $(DOCKER_NAME); exit 1; else sleep 1; fi; done
+		$(BUILDER_IMAGE) \
+		sh -c "tail -f --pid=\$$($(BAZEL) info server_pid)"
 .PHONY: bazel-server-start
 
 bazel-shutdown: ## Shuts down a running bazel server.
-	@docker exec --user $(UID):$(GID) $(DOCKER_NAME) $(BAZEL) shutdown; rc=$$?; docker kill $(DOCKER_NAME) || [[ $$rc -ne 0 ]]
+	@docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) $(BAZEL) shutdown; \
+	       rc=$$?; docker kill $(DOCKER_NAME) || [[ $$rc -ne 0 ]]
 .PHONY: bazel-shutdown
 
 bazel-alias: ## Emits an alias that can be used within the shell.
-	@echo "alias bazel='docker exec --user $(UID):$(GID) -i $(DOCKER_NAME) bazel'"
+	@echo "alias bazel='docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) bazel'"
 .PHONY: bazel-alias
 
 bazel-server: ## Ensures that the server exists. Used as an internal target.
-	@docker exec $(DOCKER_NAME) true || $(MAKE) bazel-server-start
+	@docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) true || $(MAKE) bazel-server-start
 .PHONY: bazel-server
 
-build_cmd = docker exec --user $(UID):$(GID) -i $(DOCKER_NAME) sh -o pipefail -c '$(BAZEL) build $(OPTIONS) $(TARGETS)'
+build_cmd = docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) sh -o pipefail -c '$(BAZEL) build $(OPTIONS) $(TARGETS)'
 
 build_paths = $(build_cmd) 2>&1 \
 		| tee /proc/self/fd/2 \
@@ -126,9 +157,9 @@ sudo: bazel-server
 .PHONY: sudo
 
 test: bazel-server
-	@docker exec --user $(UID):$(GID) -i $(DOCKER_NAME) $(BAZEL) test $(OPTIONS) $(TARGETS)
+	@docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) $(BAZEL) test $(OPTIONS) $(TARGETS)
 .PHONY: test
 
 query: bazel-server
-	@docker exec --user $(UID):$(GID) -i $(DOCKER_NAME) $(BAZEL) query $(OPTIONS) '$(TARGETS)'
+	@docker exec $(FULL_DOCKER_EXEC_OPTIONS) $(DOCKER_NAME) $(BAZEL) query $(OPTIONS) '$(TARGETS)'
 .PHONY: query
diff --git a/tools/go_generics/BUILD b/tools/go_generics/BUILD
index 32a949c93..558826bf1 100644
--- a/tools/go_generics/BUILD
+++ b/tools/go_generics/BUILD
@@ -12,27 +12,3 @@ go_binary(
     visibility = ["//:sandbox"],
     deps = ["//tools/go_generics/globals"],
 )
-
-genrule(
-    name = "go_generics_tests",
-    srcs = glob(["generics_tests/**"]) + [":go_generics"],
-    outs = ["go_generics_tests.tgz"],
-    cmd = "tar -czvhf $@ $(SRCS)",
-)
-
-genrule(
-    name = "go_generics_test_bundle",
-    srcs = [
-        ":go_generics_tests.tgz",
-        ":go_generics_unittest.sh",
-    ],
-    outs = ["go_generics_test.sh"],
-    cmd = "cat $(location :go_generics_unittest.sh) $(location :go_generics_tests.tgz) > $@",
-    executable = True,
-)
-
-sh_test(
-    name = "go_generics_test",
-    size = "small",
-    srcs = ["go_generics_test.sh"],
-)
diff --git a/tools/go_generics/defs.bzl b/tools/go_generics/defs.bzl
index ec047a644..33329cf28 100644
--- a/tools/go_generics/defs.bzl
+++ b/tools/go_generics/defs.bzl
@@ -100,20 +100,21 @@ def _go_template_instance_impl(ctx):
 
     # Build the argument list.
     args = ["-i=%s" % template.file.path, "-o=%s" % output.path]
-    args += ["-p=%s" % ctx.attr.package]
+    if ctx.attr.package:
+        args.append("-p=%s" % ctx.attr.package)
 
     if len(ctx.attr.prefix) > 0:
-        args += ["-prefix=%s" % ctx.attr.prefix]
+        args.append("-prefix=%s" % ctx.attr.prefix)
 
     if len(ctx.attr.suffix) > 0:
-        args += ["-suffix=%s" % ctx.attr.suffix]
+        args.append("-suffix=%s" % ctx.attr.suffix)
 
     args += [("-t=%s=%s" % (p[0], p[1])) for p in ctx.attr.types.items()]
     args += [("-c=%s=%s" % (p[0], p[1])) for p in ctx.attr.consts.items()]
     args += [("-import=%s=%s" % (p[0], p[1])) for p in ctx.attr.imports.items()]
 
     if ctx.attr.anon:
-        args += ["-anon"]
+        args.append("-anon")
 
     ctx.actions.run(
         inputs = [template.file],
@@ -151,7 +152,7 @@ go_template_instance = rule(
         "consts": attr.string_dict(),
         "imports": attr.string_dict(),
         "anon": attr.bool(mandatory = False, default = False),
-        "package": attr.string(mandatory = True),
+        "package": attr.string(mandatory = False),
         "out": attr.output(mandatory = True),
         "_tool": attr.label(executable = True, cfg = "host", default = Label("//tools/go_generics")),
     },
diff --git a/tools/go_generics/generics_tests/all_stmts/opts.txt b/tools/go_generics/generics_tests/all_stmts/opts.txt
deleted file mode 100644
index c9d0e09bf..000000000
--- a/tools/go_generics/generics_tests/all_stmts/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=Q
diff --git a/tools/go_generics/generics_tests/all_types/opts.txt b/tools/go_generics/generics_tests/all_types/opts.txt
deleted file mode 100644
index c9d0e09bf..000000000
--- a/tools/go_generics/generics_tests/all_types/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=Q
diff --git a/tools/go_generics/generics_tests/anon/opts.txt b/tools/go_generics/generics_tests/anon/opts.txt
deleted file mode 100644
index a5e9d26de..000000000
--- a/tools/go_generics/generics_tests/anon/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=Q -suffix=New -anon
diff --git a/tools/go_generics/generics_tests/consts/opts.txt b/tools/go_generics/generics_tests/consts/opts.txt
deleted file mode 100644
index 4fb59dce8..000000000
--- a/tools/go_generics/generics_tests/consts/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--c=c1=20 -c=z=600 -c=v=3.3 -c=s="def" -c=A=20 -c=C=100 -c=S="def" -c=T="ABC"
diff --git a/tools/go_generics/generics_tests/imports/opts.txt b/tools/go_generics/generics_tests/imports/opts.txt
deleted file mode 100644
index 87324be79..000000000
--- a/tools/go_generics/generics_tests/imports/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=sync.Mutex -c=n=math.Uint32 -c=m=math.Uint64 -import=sync=sync -import=math=mymathpath
diff --git a/tools/go_generics/generics_tests/remove_typedef/opts.txt b/tools/go_generics/generics_tests/remove_typedef/opts.txt
deleted file mode 100644
index 9c8ecaada..000000000
--- a/tools/go_generics/generics_tests/remove_typedef/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=U
diff --git a/tools/go_generics/generics_tests/simple/opts.txt b/tools/go_generics/generics_tests/simple/opts.txt
deleted file mode 100644
index 7832ef66f..000000000
--- a/tools/go_generics/generics_tests/simple/opts.txt
+++ /dev/null
@@ -1 +0,0 @@
--t=T=Q -suffix=New
diff --git a/tools/go_generics/go_generics_unittest.sh b/tools/go_generics/go_generics_unittest.sh
deleted file mode 100755
index 44b22db91..000000000
--- a/tools/go_generics/go_generics_unittest.sh
+++ /dev/null
@@ -1,70 +0,0 @@
-#!/bin/bash
-
-# 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.
-
-# Bash "safe-mode":  Treat command failures as fatal (even those that occur in
-# pipes), and treat unset variables as errors.
-set -eu -o pipefail
-
-# This file will be generated as a self-extracting shell script in order to
-# eliminate the need for any runtime dependencies. The tarball at the end will
-# include the go_generics binary, as well as a subdirectory named
-# generics_tests. See the BUILD file for more information.
-declare -r temp=$(mktemp -d)
-function cleanup() {
-  rm -rf "${temp}"
-}
-# trap cleanup EXIT
-
-# Print message in "$1" then exit with status 1.
-function die () {
-  echo "$1" 1>&2
-  exit 1
-}
-
-# This prints the line number of __BUNDLE__ below, that should be the last line
-# of this script. After that point, the concatenated archive will be the
-# contents.
-declare -r tgz=`awk '/^__BUNDLE__/ {print NR + 1; exit 0; }' $0`
-tail -n+"${tgz}" $0 | tar -xzv -C "${temp}"
-
-# The target for the test.
-declare -r binary="$(find ${temp} -type f -a -name go_generics)"
-declare -r input_dirs="$(find ${temp} -type d -a -name generics_tests)/*"
-
-# Go through all test cases.
-for f in ${input_dirs}; do
-  base=$(basename "${f}")
-
-  # Run go_generics on the input file.
-  opts=$(head -n 1 ${f}/opts.txt)
-  out="${f}/output/generated.go"
-  expected="${f}/output/output.go"
-  ${binary} ${opts} "-i=${f}/input.go" "-o=${out}" || die "go_generics failed for test case \"${base}\""
-
-  # Compare the outputs.
-  diff ${expected} ${out}
-  if [ $? -ne 0 ]; then
-    echo "Expected:"
-    cat ${expected}
-    echo "Actual:"
-    cat ${out}
-    die "Actual output is different from expected for test \"${base}\""
-  fi
-done
-
-echo "PASS"
-exit 0
-__BUNDLE__
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..a4a7c775a
--- /dev/null
+++ b/tools/go_generics/tests/all_stmts/BUILD
@@ -0,0 +1,16 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/all_stmts/input.go b/tools/go_generics/tests/all_stmts/input.go
index 4791d1ff1..4791d1ff1 100644
--- a/tools/go_generics/generics_tests/all_stmts/input.go
+++ b/tools/go_generics/tests/all_stmts/input.go
diff --git a/tools/go_generics/generics_tests/all_stmts/output/output.go b/tools/go_generics/tests/all_stmts/output.go
index a53d84535..a53d84535 100644
--- a/tools/go_generics/generics_tests/all_stmts/output/output.go
+++ b/tools/go_generics/tests/all_stmts/output.go
diff --git a/tools/go_generics/tests/all_types/BUILD b/tools/go_generics/tests/all_types/BUILD
new file mode 100644
index 000000000..60b1fd314
--- /dev/null
+++ b/tools/go_generics/tests/all_types/BUILD
@@ -0,0 +1,16 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/all_types/input.go b/tools/go_generics/tests/all_types/input.go
index 3575d02ec..6f85bbb69 100644
--- a/tools/go_generics/generics_tests/all_types/input.go
+++ b/tools/go_generics/tests/all_types/input.go
@@ -14,7 +14,9 @@
 
 package tests
 
-import "./lib"
+import (
+	"./lib"
+)
 
 type T int
 
diff --git a/tools/go_generics/generics_tests/all_types/lib/lib.go b/tools/go_generics/tests/all_types/lib/lib.go
index 988786496..988786496 100644
--- a/tools/go_generics/generics_tests/all_types/lib/lib.go
+++ b/tools/go_generics/tests/all_types/lib/lib.go
diff --git a/tools/go_generics/generics_tests/all_types/output/output.go b/tools/go_generics/tests/all_types/output.go
index 41fd147a1..c0bbebfe7 100644
--- a/tools/go_generics/generics_tests/all_types/output/output.go
+++ b/tools/go_generics/tests/all_types/output.go
@@ -14,7 +14,9 @@
 
 package main
 
-import "./lib"
+import (
+	"./lib"
+)
 
 type newType struct {
 	a Q
diff --git a/tools/go_generics/tests/anon/BUILD b/tools/go_generics/tests/anon/BUILD
new file mode 100644
index 000000000..ef24f4b25
--- /dev/null
+++ b/tools/go_generics/tests/anon/BUILD
@@ -0,0 +1,18 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/anon/input.go b/tools/go_generics/tests/anon/input.go
index 44086d522..44086d522 100644
--- a/tools/go_generics/generics_tests/anon/input.go
+++ b/tools/go_generics/tests/anon/input.go
diff --git a/tools/go_generics/generics_tests/anon/output/output.go b/tools/go_generics/tests/anon/output.go
index 160cddf79..7fa791853 100644
--- a/tools/go_generics/generics_tests/anon/output/output.go
+++ b/tools/go_generics/tests/anon/output.go
@@ -35,8 +35,8 @@ func (f FooNew) GetBar(name string) Q {
 
 func foobarNew() {
 	a := BazNew{}
-	a.Q = 0 // should not be renamed, this is a limitation
+	a.Q = 0
 
 	b := otherpkg.UnrelatedType{}
-	b.Q = 0 // should not be renamed, this is a limitation
+	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..fd7caccad
--- /dev/null
+++ b/tools/go_generics/tests/consts/BUILD
@@ -0,0 +1,23 @@
+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",
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/consts/input.go b/tools/go_generics/tests/consts/input.go
index 04b95fcc6..04b95fcc6 100644
--- a/tools/go_generics/generics_tests/consts/input.go
+++ b/tools/go_generics/tests/consts/input.go
diff --git a/tools/go_generics/generics_tests/consts/output/output.go b/tools/go_generics/tests/consts/output.go
index 18d316cc9..18d316cc9 100644
--- a/tools/go_generics/generics_tests/consts/output/output.go
+++ b/tools/go_generics/tests/consts/output.go
diff --git a/tools/go_generics/tests/defs.bzl b/tools/go_generics/tests/defs.bzl
new file mode 100644
index 000000000..6277c3947
--- /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,
+)
+
+def go_generics_test(name, inputs, output, types = None, consts = None, **kwargs):
+    """Instantiates a generics test.
+
+    Args:
+        name: the name of the test.
+        inputs: all the input files.
+        output: the output files.
+        types: the template types (dictionary).
+        consts: the template consts (dictionary).
+        **kwargs: additional arguments for the template_instance.
+    """
+    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..a86223d41
--- /dev/null
+++ b/tools/go_generics/tests/imports/BUILD
@@ -0,0 +1,24 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/imports/input.go b/tools/go_generics/tests/imports/input.go
index 0f032c2a1..0f032c2a1 100644
--- a/tools/go_generics/generics_tests/imports/input.go
+++ b/tools/go_generics/tests/imports/input.go
diff --git a/tools/go_generics/generics_tests/imports/output/output.go b/tools/go_generics/tests/imports/output.go
index 2488ca58c..2488ca58c 100644
--- a/tools/go_generics/generics_tests/imports/output/output.go
+++ b/tools/go_generics/tests/imports/output.go
diff --git a/tools/go_generics/tests/remove_typedef/BUILD b/tools/go_generics/tests/remove_typedef/BUILD
new file mode 100644
index 000000000..46457cec6
--- /dev/null
+++ b/tools/go_generics/tests/remove_typedef/BUILD
@@ -0,0 +1,16 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/remove_typedef/input.go b/tools/go_generics/tests/remove_typedef/input.go
index cf632bae7..cf632bae7 100644
--- a/tools/go_generics/generics_tests/remove_typedef/input.go
+++ b/tools/go_generics/tests/remove_typedef/input.go
diff --git a/tools/go_generics/generics_tests/remove_typedef/output/output.go b/tools/go_generics/tests/remove_typedef/output.go
index d44fd8e1c..d44fd8e1c 100644
--- a/tools/go_generics/generics_tests/remove_typedef/output/output.go
+++ b/tools/go_generics/tests/remove_typedef/output.go
diff --git a/tools/go_generics/tests/simple/BUILD b/tools/go_generics/tests/simple/BUILD
new file mode 100644
index 000000000..4b9265ea4
--- /dev/null
+++ b/tools/go_generics/tests/simple/BUILD
@@ -0,0 +1,17 @@
+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",
+    },
+)
+
+# @unused
+glaze_ignore = [
+    "input.go",
+    "output.go",
+]
diff --git a/tools/go_generics/generics_tests/simple/input.go b/tools/go_generics/tests/simple/input.go
index 2a917f16c..2a917f16c 100644
--- a/tools/go_generics/generics_tests/simple/input.go
+++ b/tools/go_generics/tests/simple/input.go
diff --git a/tools/go_generics/generics_tests/simple/output/output.go b/tools/go_generics/tests/simple/output.go
index 6bfa0b25b..6bfa0b25b 100644
--- a/tools/go_generics/generics_tests/simple/output/output.go
+++ b/tools/go_generics/tests/simple/output.go