bazel: native go-mockgen in Bazel (#60386)

Adds a new:
- gazelle generator
- rule + rule targets + catchall target
for generating go-mockgen mocks & testing for their being up-to-date.

Each go_mockgen macro invocation adds targets for generating mocks, copying to the source tree, as well as testing whether the current source tree mocks are up-to-date.

How to use this: `bazel run //dev:go_mockgen` for the catch-all, or `bazel run //some/target:generate_mocks` for an individual package, and `bazel test //some/target:generate_mocks_tests` to test for up-to-date-ness. There is no catch-all for testing

This currently uses a fork of go-mockgen, with an open PR for upstream here: derision-test/go-mockgen#50.

Closes https://github.com/sourcegraph/sourcegraph/issues/60099

## Test plan

Extensive testing during development, including the following cases:
- Deleting a generated file and its entry in a go_library/go_test `srcs` attribute list and then re-running `sg bazel configure`
- Adding a non-existent output directory to mockgen.test.yaml and running the bash one-liner emitted to prepare the workspace for rerunning `sg bazel configure`

The existing config tests a lot of existing paths anyway (creating mocks for a 3rd party library's interface, entries for a given output file in >1 config file etc)

BUILD.bazel

@@ -23,7 +23,7 @@ load("@buildifier_prebuilt//:rules.bzl", "buildifier")
 # gazelle:js_npm_package_target_name {dirname}_pkg
 
 # Enable: Aspect javascript, standard go
-# gazelle:lang js,go,proto
+# gazelle:lang js,go,proto,gomockgen
 
 # Enable race detection for all go_test rules.
 # gazelle:map_kind go_test go_test //dev:go_defs.bzl
@@ -212,6 +212,7 @@ gazelle_binary(
         # Gazelle-buf does not include the Go plugin by default, so we have to add it
         # ourselves.
         "@bazel_gazelle//language/go:go_default_library",
+        "//dev/go-mockgen-gazelle:go-mockgen-gazelle",
         # Bundled with aspect-cli, but we're missing out on buf that way
         "@aspect_cli//gazelle/js:js",
         # Loads the Buf extension
@@ -335,7 +336,7 @@ exports_files([
     # under certain conditions. See //ui/assets/...
     "CONTRIBUTING.md",
     ".swcrc",
-])
+] + glob(["mockgen*.yaml"]))
 
 # sg msp settings
 

WORKSPACE

@@ -151,6 +151,13 @@ http_archive(
     url = "https://github.com/aspect-build/aspect-cli/archive/5.8.20.tar.gz",
 )
 
+http_archive(
+    name = "rules_multirun",
+    sha256 = "9cd384e42b2da00104f0e18f25e66285aa21f64b573c667638a7a213206885ab",
+    strip_prefix = "rules_multirun-0.6.1",
+    url = "https://github.com/keith/rules_multirun/archive/refs/tags/0.6.1.tar.gz",
+)
+
 # hermetic_cc_toolchain setup ================================
 HERMETIC_CC_TOOLCHAIN_VERSION = "v2.2.1"
 

cmd/cody-gateway/internal/auth/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -44,3 +45,14 @@ go_test(
         "@com_github_vektah_gqlparser_v2//gqlerror",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = ["@com_github_gregjones_httpcache//:httpcache"],
+)

cmd/cody-gateway/internal/dotcom/BUILD.bazel

@@ -1,6 +1,7 @@
 load("//dev:go_defs.bzl", "go_test")
 load("//dev:write_generated_to_source_files.bzl", "write_generated_to_source_files")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("//dev:go_mockgen.bzl", "go_mockgen")
 
 go_library(
     name = "dotcom",
@@ -47,3 +48,14 @@ go_test(
     embed = [":dotcom"],
     deps = ["@com_github_stretchr_testify//assert"],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = ["@com_github_khan_genqlient//graphql"],
+)

cmd/executor/internal/worker/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -64,3 +65,22 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [
+        "//cmd/executor/internal/util",
+        "//cmd/executor/internal/worker/cmdlogger",
+        "//cmd/executor/internal/worker/command",
+        "//cmd/executor/internal/worker/files",
+        "//cmd/executor/internal/worker/runner",
+        "//cmd/executor/internal/worker/runtime",
+        "//cmd/executor/internal/worker/workspace",
+    ],
+)

cmd/executor/internal/worker/cmdlogger/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 load("//dev:go_defs.bzl", "go_test")
 
@@ -28,3 +29,14 @@ go_test(
         "@com_github_sourcegraph_log//logtest",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":cmdlogger"],
+)

cmd/executor/internal/worker/command/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -72,3 +73,17 @@ go_test(
         "@io_k8s_utils//pointer",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [
+        ":command",
+        "//cmd/executor/internal/worker/cmdlogger",
+    ],
+)

cmd/executor/internal/worker/files/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -26,3 +27,14 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":files"],
+)

cmd/executor/internal/worker/runner/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -60,3 +61,18 @@ go_test(
         "@io_k8s_client_go//testing",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [
+        "//cmd/executor/internal/worker/cmdlogger",
+        "//cmd/executor/internal/worker/command",
+        "//cmd/executor/internal/worker/files",
+    ],
+)

cmd/executor/internal/worker/runtime/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -56,3 +57,20 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [
+        "//cmd/executor/internal/util",
+        "//cmd/executor/internal/worker/cmdlogger",
+        "//cmd/executor/internal/worker/command",
+        "//cmd/executor/internal/worker/files",
+        "//cmd/executor/internal/worker/workspace",
+    ],
+)

cmd/executor/internal/worker/workspace/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -49,3 +50,19 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [
+        "//cmd/executor/internal/util",
+        "//cmd/executor/internal/worker/cmdlogger",
+        "//cmd/executor/internal/worker/command",
+        "//cmd/executor/internal/worker/files",
+    ],
+)

cmd/frontend/backend/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -133,3 +134,14 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_temp.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":backend"],
+)

cmd/frontend/internal/executorqueue/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -54,3 +55,14 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":executorqueue"],
+)

cmd/frontend/internal/executorqueue/queues/batches/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -58,3 +59,14 @@ go_test(
         "@in_gopkg_yaml_v2//:yaml_v2",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":batches"],
+)

cmd/frontend/internal/httpapi/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -141,3 +142,14 @@ go_test(
         "@org_golang_google_protobuf//testing/protocmp",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = ["//internal/httpcli"],
+)

cmd/frontend/internal/httpapi/releasecache/BUILD.bazel

@@ -1,3 +1,4 @@
+load("//dev:go_mockgen.bzl", "go_mockgen")
 load("//dev:go_defs.bzl", "go_test")
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
@@ -58,3 +59,14 @@ go_test(
         "@com_github_stretchr_testify//require",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":releasecache"],
+)

cmd/gitserver/internal/BUILD.bazel

@@ -1,5 +1,6 @@
 load("@io_bazel_rules_go//go:def.bzl", "go_library")
 load("//dev:go_defs.bzl", "go_test")
+load("//dev:go_mockgen.bzl", "go_mockgen")
 
 go_library(
     name = "internal",
@@ -22,7 +23,8 @@ go_library(
     ],
     embedsrcs = ["sg_maintenance.sh"],
     importpath = "github.com/sourcegraph/sourcegraph/cmd/gitserver/internal",
-    visibility = ["//cmd/gitserver:__subpackages__"],
+    # visibility = ["//cmd/gitserver:__subpackages__"],
+    visibility = ["//visibility:public"],
     deps = [
         "//cmd/frontend/envvar",
         "//cmd/gitserver/internal/accesslog",
@@ -149,3 +151,14 @@ go_test(
         "@org_golang_x_time//rate",
     ],
 )
+
+go_mockgen(
+    name = "generate_mocks",
+    out = "mocks_test.go",
+    manifests = [
+        "//:mockgen.yaml",
+        "//:mockgen.test.yaml",
+        "//:mockgen.temp.yaml",
+    ],
+    deps = [":internal"],
+)