Move ToolsRepository out of Environment

Other fields will follow (is_skylark, phase, callerLabel).
The goal is to make Environment (and more generally Skylark) less dependent
on Bazel.

--
MOS_MIGRATED_REVID=137386248

1 files changed, 38 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkUtils.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkUtils.java
new file mode 100644
index 0000000000..875586f4f0
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkUtils.java
@@ -0,0 +1,38 @@
+// Copyright 2016 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.
+
+package com.google.devtools.build.lib.syntax;
+
+/** This class contains Bazel-specific functions to extend or interoperate with Skylark. */
+public final class SkylarkUtils {
+
+  public static final String TOOLS_REPOSITORY = "$tools_repository";
+
+  /** Unsafe version of Environment#update */
+  private static void updateEnv(Environment env, String key, Object value) {
+    try {
+      env.update(key, value);
+    } catch (EvalException e) {
+      throw new AssertionError(e);
+    }
+  }
+
+  public static void setToolsRepository(Environment env, String toolsRepository) {
+    updateEnv(env, TOOLS_REPOSITORY, toolsRepository);
+  }
+
+  public static String getToolsRepository(Environment env) {
+    return (String) env.lookup(TOOLS_REPOSITORY);
+  }
+}