Add GoContext (bazel-contrib#1140)

* Add GoContext This collects up all dependancies that were on the toolchain, but shoudld be in target configuration (rather than host) and migrates them to a common go_context_data dependancy. It then adds a GoContext object, that holds the toolchain, build mode, standard library and all mode specific attributes. go_context(ctx) will build one of these and prepare to use it. This simplifies a lot of the logic in the rules, and helps enforce the isolation of action methods from ctx attributes. * Review feedback plus documentation
sluongng · Dec 15, 2017 · 9031d58 · 9031d58
1 parent ecc72b5
commit 9031d58
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Showing 43 changed files with 826 additions and 770 deletions.
diff --git a/BUILD.bazel b/BUILD.bazel
@@ -2,6 +2,17 @@ load("@io_bazel_rules_go//go:def.bzl", "gazelle", "go_prefix", "go_path", "go_ve
 load("@io_bazel_rules_go//go/private:tools/lines_sorted_test.bzl", "lines_sorted_test")
 load("@io_bazel_rules_go//go/private:rules/info.bzl", "go_info")
 load("@io_bazel_rules_go//proto:go_proto_library.bzl", "go_google_protobuf")
+load("@io_bazel_rules_go//go/private:context.bzl", "go_context_data")
+
+go_context_data(
+    name = "go_context_data",
+    strip = select({
+        "@io_bazel_rules_go//go/private:strip-always": "always",
+        "@io_bazel_rules_go//go/private:strip-sometimes": "sometimes",
+        "@io_bazel_rules_go//go/private:strip-never": "never",
+    }),
+    visibility = ["//visibility:public"],
+)
 
 # gazelle:prefix github.com/bazelbuild/rules_go
 

diff --git a/examples/bindata/BUILD.bazel b/examples/bindata/BUILD.bazel
@@ -1,5 +1,5 @@
 load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
-load("@io_bazel_rules_go//examples/bindata:bindata.bzl", "bindata")
+load("@io_bazel_rules_go//extras:bindata.bzl", "bindata")
 
 bindata(
     name = "data",

diff --git a/extras/BUILD.bazel b/extras/BUILD.bazel
@@ -0,0 +1,5 @@
+filegroup(
+    name = "all_rules",
+    srcs = glob(["*.bzl"]) + ["//go/private:all_rules"],
+    visibility = ["//visibility:public"],
+)
diff --git a/examples/bindata/bindata.bzl → extras/bindata.bzl b/examples/bindata/bindata.bzl → extras/bindata.bzl
@@ -1,8 +1,8 @@
-load("@io_bazel_rules_go//go/private:go_repository.bzl", "go_repository")
-load("@io_bazel_rules_go//go/private:common.bzl", "declare_file")
+load("@io_bazel_rules_go//go:def.bzl", "go_context")
 
 def _bindata_impl(ctx):
-  out = declare_file(ctx, ext=".go")
+  go = go_context(ctx)
+  out = go.declare_file(go, ext=".go")
   arguments = ctx.actions.args()
   arguments.add([
       "-o", out.path,
@@ -35,5 +35,7 @@ bindata = rule(
         "compress": attr.bool(default=True),
         "metadata": attr.bool(default=False),
         "_bindata":  attr.label(allow_files=True, single_file=True, default=Label("@com_github_jteeuwen_go_bindata//go-bindata:go-bindata")),
+        "_go_context_data": attr.label(default=Label("@io_bazel_rules_go//:go_context_data")),
     },
+    toolchains = ["@io_bazel_rules_go//go:toolchain"],
 )
diff --git a/go/private/tools/embed_data.bzl → extras/embed_data.bzl b/go/private/tools/embed_data.bzl → extras/embed_data.bzl
@@ -12,18 +12,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-load("@io_bazel_rules_go//go/private:common.bzl",
-    "declare_file",
-)
-load("@io_bazel_rules_go//go/private:rules/helpers.bzl",
-    "new_go_library",
-    "library_to_source",
-)
-load("@io_bazel_rules_go//go/private:mode.bzl",
-    "get_mode",
+load("@io_bazel_rules_go//go/private:context.bzl", #TODO: This ought to be def
+    "go_context",
 )
 
 def _go_embed_data_impl(ctx):
+  go = go_context(ctx)
   if ctx.attr.src and ctx.attr.srcs:
     fail("%s: src and srcs attributes cannot both be specified" % ctx.label)
   if ctx.attr.src and ctx.attr.flatten:
@@ -43,7 +37,7 @@ def _go_embed_data_impl(ctx):
     if package == "":
       fail("%s: must provide package attribute for go_embed_data rules in the repository root directory" % ctx.label)
 
-  out = declare_file(ctx, ext=".go")
+  out = go.declare_file(go, ext=".go")
   args.add([
     "-workspace", ctx.workspace_name,
     "-label", str(ctx.label),
@@ -57,9 +51,8 @@ def _go_embed_data_impl(ctx):
     args.add("-string")
   args.add(srcs)
 
-  mode = get_mode(ctx, ctx.attr._go_toolchain_flags)
-  library = new_go_library(ctx, srcs=srcs)
-  source = library_to_source(ctx, ctx.attr, library, mode)
+  library = go.new_library(go, srcs=srcs)
+  source = go.library_to_source(go, ctx.attr, library, ctx.coverage_instrumented())
 
   ctx.actions.run(
       outputs = [out],
@@ -87,7 +80,7 @@ go_embed_data = rule(
             executable = True,
             cfg = "host",
         ),
-        "_go_toolchain_flags": attr.label(default=Label("@io_bazel_rules_go//go/private:go_toolchain_flags")),
+        "_go_context_data": attr.label(default=Label("@io_bazel_rules_go//:go_context_data")),
     },
     toolchains = ["@io_bazel_rules_go//go:toolchain"],
 )

diff --git a/go/core.rst b/go/core.rst
@@ -6,7 +6,7 @@ Core go rules
 .. _gazelle: tools/gazelle/README.rst
 .. _build constraints: http://golang.org/pkg/go/build/
 .. _GoLibrary: providers.rst#GoLibrary
-.. _GoSourceList: providers.rst#GoSourceList
+.. _GoSource: providers.rst#GoSource
 .. _GoArchive: providers.rst#GoArchive
 .. _cgo: http://golang.org/cmd/cgo/
 .. _"Make variable": https://docs.bazel.build/versions/master/be/make-variables.html
@@ -15,6 +15,8 @@ Core go rules
 .. _cc library deps: https://docs.bazel.build/versions/master/be/c-cpp.html#cc_library.deps
 .. _pure: modes.rst#pure
 .. _static: modes.rst#static
+.. _goos: modes.rst#goos
+.. _goarch: modes.rst#goarch
 .. _mode attributes: modes.rst#mode-attributes
 
 .. role:: param(kbd)
@@ -58,7 +60,7 @@ Providers
 ^^^^^^^^^
 
 * GoLibrary_
-* GoSourceList_
+* GoSource_
 * GoArchive_
 
 Attributes
@@ -94,7 +96,7 @@ Attributes
 | :param:`embed`             | :type:`label_list`          | :value:`None`                         |
 +----------------------------+-----------------------------+---------------------------------------+
 | List of Go libraries this test library directly.                                                 |
-| These may be go_library rules or compatible rules with the GoSourceList_ provider.               |
+| These may be go_library rules or compatible rules with the GoLibrary_ provider.                  |
 | These can provide both :param:`srcs` and :param:`deps` to this library.                          |
 | See Embedding_ for more information about how and when to use this.                              |
 +----------------------------+-----------------------------+---------------------------------------+
@@ -167,7 +169,8 @@ Providers
 ^^^^^^^^^
 
 * GoLibrary_
-* GoSourceList_
+* GoSource_
+* GoArchive_
 
 Attributes
 ^^^^^^^^^^
@@ -202,7 +205,7 @@ Attributes
 | :param:`embed`             | :type:`label_list`          | :value:`None`                         |
 +----------------------------+-----------------------------+---------------------------------------+
 | List of Go libraries this binary embeds directly.                                                |
-| These may be go_library rules or compatible rules with the GoSourceList_ provider.               |
+| These may be go_library rules or compatible rules with the GoLibrary_ provider.                  |
 | These can provide both :param:`srcs` and :param:`deps` to this binary.                           |
 | See Embedding_ for more information about how and when to use this.                              |
 +----------------------------+-----------------------------+---------------------------------------+
@@ -223,6 +226,26 @@ Attributes
 | This is one of the `mode attributes`_ that controls whether to link in static_ mode.             |
 | It should be one of :value:`on`, :value:`off` or :value:`auto`.                                  |
 +----------------------------+-----------------------------+---------------------------------------+
+| :param:`goos`              | :type:`string`              | :value:`auto`                         |
++----------------------------+-----------------------------+---------------------------------------+
+| This is one of the `mode attributes`_ that controls which goos_ to compile and link for.         |
+|                                                                                                  |
+| If set to anything other than :value:`auto` this overrideds the default as set by the current    |
+| target platform, and allows for single builds to make binaries for multiple architectures.       |
+|                                                                                                  |
+| Because this has no control over the cc toolchain, it does not work for cgo, so if this          |
+| attribute is set then :param:`pure` must be set to :value:`on`.                                  |
++----------------------------+-----------------------------+---------------------------------------+
+| :param:`goarch`            | :type:`string`              | :value:`auto`                         |
++----------------------------+-----------------------------+---------------------------------------+
+| This is one of the `mode attributes`_ that controls which goarch_ to compile and link for.       |
+|                                                                                                  |
+| If set to anything other than :value:`auto` this overrideds the default as set by the current    |
+| target platform, and allows for single builds to make binaries for multiple architectures.       |
+|                                                                                                  |
+| Because this has no control over the cc toolchain, it does not work for cgo, so if this          |
+| attribute is set then :param:`pure` must be set to :value:`on`.                                  |
++----------------------------+-----------------------------+---------------------------------------+
 | :param:`gc_goopts`         | :type:`string_list`         | :value:`[]`                           |
 +----------------------------+-----------------------------+---------------------------------------+
 | List of flags to add to the Go compilation command when using the gc compiler.                   |
@@ -314,7 +337,7 @@ Attributes
 | :param:`embed`             | :type:`label_list`          | :value:`None`                         |
 +----------------------------+-----------------------------+---------------------------------------+
 | List of Go libraries this test embeds directly.                                                  |
-| These may be go_library rules or compatible rules with the GoSourceList_ provider.               |
+| These may be go_library rules or compatible rules with the GoLibrary_ provider.                  |
 | These can provide both :param:`srcs` and :param:`deps` to this test.                             |
 | See Embedding_ for more information about how and when to use this.                              |
 +----------------------------+-----------------------------+---------------------------------------+
@@ -438,7 +461,8 @@ This is used as a way of easily declaring a common set of sources re-used in mul
 Providers
 ^^^^^^^^^
 
-* GoSourceList_
+* GoLibrary_
+* GoSource_
 
 Attributes
 ^^^^^^^^^^
@@ -464,7 +488,7 @@ Attributes
 | :param:`embed`             | :type:`label_list`          | :value:`None`                         |
 +----------------------------+-----------------------------+---------------------------------------+
 | List of sources to directly embed in this list.                                                  |
-| These may be go_library rules or compatible rules with the GoSourceList_ provider.               |
+| These may be go_library rules or compatible rules with the GoSource_ provider.                   |
 | These can provide both :param:`srcs` and :param:`deps` to this library.                          |
 | See Embedding_ for more information about how and when to use this.                              |
 +----------------------------+-----------------------------+---------------------------------------+

diff --git a/go/def.bzl b/go/def.bzl
@@ -12,6 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+load("@io_bazel_rules_go//go/private:context.bzl",
+    go_context = "go_context",
+)
 load("@io_bazel_rules_go//go/private:go_repository.bzl",
     "go_repository",
 )
@@ -22,7 +25,7 @@ load("@io_bazel_rules_go//go/private:repositories.bzl",
     "go_rules_dependencies",
     "go_register_toolchains",
 )
-load("@io_bazel_rules_go//go/private:toolchain.bzl",
+load("@io_bazel_rules_go//go/private:sdk.bzl",
     go_host_sdk = "go_host_sdk",
     go_download_sdk = "go_download_sdk",
     go_local_sdk = "go_local_sdk",
@@ -42,7 +45,7 @@ load("@io_bazel_rules_go//go/private:rules/wrappers.bzl",
 load("@io_bazel_rules_go//go/private:rules/source.bzl",
     _go_source = "go_source",
 )
-load("@io_bazel_rules_go//go/private:tools/embed_data.bzl",
+load("@io_bazel_rules_go//extras:embed_data.bzl",
     "go_embed_data",
 )
 load("@io_bazel_rules_go//go/private:tools/gazelle.bzl",

diff --git a/go/modes.rst b/go/modes.rst
@@ -63,7 +63,7 @@ The entire transitive set of libraries that a leaf depends on are built in the m
 the binary rule. The compiled libraries are distinct and multiple modes can be built in a single pass,
 but are shared between leaves building in the same mode.
 
-Currently only static_ and pure_ can be specified as attributes.
+Currently only static_, pure_, goos_ and goarch_ can be specified as attributes.
 Both of these can take one of the values "on", "off" or "auto", and "auto" is the default.
 
 +--------------+-------------------------------------------------------------------------+
@@ -88,6 +88,8 @@ following fields that control the bevhaviour of those actions:
 * link_
 * debug_
 * strip_
+* goos_
+* goarch_
 
 Build modes
 -----------
@@ -148,6 +150,16 @@ strip
 
 Causes debugging information to be stripped from the binaries.
 
+goos
+~~~~
+
+This controls which operating system to target.
+
+goarch
+~~~~~~
+
+This controls which architecture to target.
+
 Using build modes
 -----------------
 
@@ -204,3 +216,15 @@ the mode of tests by using
 .. code::
 
     bazel test --features=race //...
+
+but in general it is strongly recommended instead to turn it on for specific tests.
+
+.. code::
+
+    go_test(
+        name = "go_default_test",
+        srcs = ["lib_test.go"],
+        embed = [":go_default_library"],
+        race = "on",
+  )
+
diff --git a/go/private/BUILD.bazel b/go/private/BUILD.bazel
@@ -1,5 +1,3 @@
-load("@io_bazel_rules_go//go/private:go_toolchain.bzl", "go_toolchain_flags")
-
 filegroup(
     name = "all_rules",
     srcs = glob(["**/*.bzl"]),
@@ -21,12 +19,3 @@ config_setting(
     values = {"strip": "never"},
 )
 
-go_toolchain_flags(
-    name = "go_toolchain_flags",
-    strip = select({
-        "@io_bazel_rules_go//go/private:strip-always": "always",
-        "@io_bazel_rules_go//go/private:strip-sometimes": "sometimes",
-        "@io_bazel_rules_go//go/private:strip-never": "never",
-    }),
-    visibility = ["//visibility:public"],
-)
diff --git a/go/private/actions/action.bzl b/go/private/actions/action.bzl