Track paths and provide a rename hook.

This change also adds extensive testing to the p9 package via mocks. The sanity
checks and type checks are moved from the gofer into the core package, where
they can be more easily validated.

PiperOrigin-RevId: 218296768
Change-Id: I4fc3c326e7bf1e0e140a454cbacbcc6fd617ab55

1 files changed, 68 insertions, 8 deletions

diff --git a/pkg/p9/p9test/BUILD b/pkg/p9/p9test/BUILD
index d6f428e11..7c4b875ce 100644
--- a/pkg/p9/p9test/BUILD
+++ b/pkg/p9/p9test/BUILD
@@ -1,16 +1,60 @@
+load("//tools/go_stateify:defs.bzl", "go_library", "go_test")
+load("@io_bazel_rules_go//go:def.bzl", "go_binary")
+
 package(licenses = ["notice"])  # Apache 2.0
 
-load("//tools/go_stateify:defs.bzl", "go_library", "go_test")
+alias(
+    name = "mockgen",
+    actual = "@com_github_golang_mock//mockgen:mockgen",
+)
 
-go_test(
-    name = "p9test_test",
-    size = "small",
-    srcs = ["client_test.go"],
-    embed = [":p9test"],
+MOCK_SRC_PACKAGE = "gvisor.googlesource.com/gvisor/pkg/p9"
+
+# mockgen_reflect is a source file that contains mock generation code that
+# imports the p9 package and generates a specification via reflection. The
+# usual generation path must be split into two distinct parts because the full
+# source tree is not available to all build targets. Only declared depencies
+# are available (and even then, not the Go source files).
+genrule(
+    name = "mockgen_reflect",
+    testonly = 1,
+    outs = ["mockgen_reflect.go"],
+    cmd = (
+        "$(location :mockgen) " +
+        "-package p9test " +
+        "-prog_only " + MOCK_SRC_PACKAGE + " " +
+        "Attacher,File > $@"
+    ),
+    tools = [":mockgen"],
+)
+
+# mockgen_exec is the binary that includes the above reflection generator.
+# Running this binary will emit an encoded version of the p9 Attacher and File
+# structures. This is consumed by the mocks genrule, below.
+go_binary(
+    name = "mockgen_exec",
+    testonly = 1,
+    srcs = ["mockgen_reflect.go"],
     deps = [
-        "//pkg/fd",
         "//pkg/p9",
-        "//pkg/unet",
+        "@com_github_golang_mock//mockgen/model:go_default_library",
+    ],
+)
+
+# mocks consumes the encoded output above, and generates the full source for a
+# set of mocks. These are included directly in the p9test library.
+genrule(
+    name = "mocks",
+    testonly = 1,
+    outs = ["mocks.go"],
+    cmd = (
+        "$(location :mockgen) " +
+        "-package p9test " +
+        "-exec_only $(location :mockgen_exec) " + MOCK_SRC_PACKAGE + " File > $@"
+    ),
+    tools = [
+        ":mockgen",
+        ":mockgen_exec",
     ],
 )
 
@@ -18,11 +62,27 @@ go_library(
     name = "p9test",
     srcs = [
         "mocks.go",
+        "p9test.go",
     ],
     importpath = "gvisor.googlesource.com/gvisor/pkg/p9/p9test",
     visibility = ["//:sandbox"],
     deps = [
         "//pkg/fd",
+        "//pkg/log",
+        "//pkg/p9",
+        "//pkg/unet",
+        "@com_github_golang_mock//gomock:go_default_library",
+    ],
+)
+
+go_test(
+    name = "client_test",
+    size = "small",
+    srcs = ["client_test.go"],
+    embed = [":p9test"],
+    deps = [
+        "//pkg/fd",
         "//pkg/p9",
+        "@com_github_golang_mock//gomock:go_default_library",
     ],
 )