Add constraint_setting and constraint_value rules, to enable defining

platform-related constraints and values.

Part of ongoing work on #2219.

--
Change-Id: Ice370ee26469f4992faf72c0c95a1a3e51a9f9e7
Reviewed-on: https://cr.bazel.build/9091
PiperOrigin-RevId: 148758190
MOS_MIGRATED_REVID=148758190

1 files changed, 48 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/ConstraintValue.java b/src/main/java/com/google/devtools/build/lib/rules/platform/ConstraintValue.java
new file mode 100644
index 0000000000..c232c92212
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/ConstraintValue.java
@@ -0,0 +1,48 @@
+// 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.
+
+package com.google.devtools.build.lib.rules.platform;
+
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.FileProvider;
+import com.google.devtools.build.lib.analysis.FilesToRunProvider;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.RunfilesProvider;
+import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
+
+/** Defines a potential value of a constraint. */
+public class ConstraintValue implements RuleConfiguredTargetFactory {
+
+  @Override
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
+
+    ConstraintSettingProvider constraint =
+        ruleContext.getPrerequisite(
+            ConstraintValueRule.CONSTRAINT_SETTING_ATTR,
+            Mode.DONT_CHECK,
+            ConstraintSettingProvider.class);
+
+    return new RuleConfiguredTargetBuilder(ruleContext)
+        .addProvider(RunfilesProvider.class, RunfilesProvider.EMPTY)
+        .addProvider(FileProvider.class, FileProvider.EMPTY)
+        .addProvider(FilesToRunProvider.class, FilesToRunProvider.EMPTY)
+        .addProvider(
+            ConstraintValueProvider.class,
+            ConstraintValueProvider.create(constraint, ruleContext.getLabel()))
+        .build();
+  }
+}