feat(builtin): export version to npm/yarn install

Author: Fabian Wiles

index.bzl

@@ -17,6 +17,7 @@
 Users should not load files under "/internal"
 """
 
+load("//internal:version.bzl", "VERSION")
 load("//internal/common:check_bazel_version.bzl", _check_bazel_version = "check_bazel_version")
 load("//internal/common:check_version.bzl", "check_version")
 load("//internal/common:copy_to_bin.bzl", _copy_to_bin = "copy_to_bin")

internal/npm_install/npm_install.bzl

@@ -21,6 +21,7 @@ as the package manager.
 See discussion in the README.
 """
 
+load("//internal:version.bzl", "VERSION")
 load("//internal/common:check_bazel_version.bzl", "check_bazel_version")
 load("//internal/common:os_name.bzl", "is_windows_os")
 load("//internal/node:node_labels.bzl", "get_node_label", "get_npm_label", "get_yarn_label")
@@ -275,6 +276,7 @@ cd /D "{root}" && "{npm}" {npm_args}
     env_key = "BAZEL_NPM_INSTALL"
     if env_key not in env.keys():
         env[env_key] = "1"
+    env["build_bazel_rules_nodejs_version"] = VERSION
 
     repository_ctx.report_progress("Running npm install on %s" % repository_ctx.attr.package_json)
     result = repository_ctx.execute(
@@ -412,6 +414,7 @@ cd /D "{root}" && "{yarn}" {yarn_args}
     env_key = "BAZEL_YARN_INSTALL"
     if env_key not in env.keys():
         env[env_key] = "1"
+    env["build_bazel_rules_nodejs_version"] = VERSION
 
     repository_ctx.report_progress("Running yarn install on %s" % repository_ctx.attr.package_json)
     result = repository_ctx.execute(

internal/version.bzl

@@ -0,0 +1,22 @@
+# Copyright 2017 The Bazel Authors. All rights reserved.
+#
+# 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.
+
+"""Version for the rules_nodejs repository
+"""
+
+# This version is synced with the version in package.json.
+# It will be automatically synced via the npm "version" script
+# that is run when running `npm version` during the release
+# process. See `Releasing` section in README.md.
+VERSION = "1.0.0"

scripts/on-version.js

@@ -4,4 +4,4 @@
 const shell = require('shelljs');
 const version = require('../package.json').version;
 
-shell.sed('-i', /^VERSION \= \"[0-9\.]*\"/, `VERSION = "${version}"`, 'index.bzl');
+shell.sed('-i', /^VERSION \= \"[0-9\.]*\"/, `VERSION = "${version}"`, 'internal/version.bzl');