Move platform lookup to new dedicated helper class.

Change-Id: I2195a3f7d60e9835bc00d6f151ea91271fdccf6f
PiperOrigin-RevId: 204954233

1 files changed, 124 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java b/src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java
new file mode 100644
index 0000000000..d9f998b803
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java
@@ -0,0 +1,124 @@
+// Copyright 2018 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.skyframe;
+
+import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
+import com.google.devtools.build.lib.analysis.platform.PlatformProviderUtils;
+import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.packages.NoSuchThingException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetFunction.ConfiguredValueCreationException;
+import com.google.devtools.build.skyframe.SkyFunction.Environment;
+import com.google.devtools.build.skyframe.SkyKey;
+import com.google.devtools.build.skyframe.ValueOrException3;
+import java.util.HashMap;
+import java.util.Map;
+import javax.annotation.Nullable;
+
+/** Helper class that looks up {@link PlatformInfo} data. */
+public class PlatformLookupUtil {
+
+  @Nullable
+  public static Map<ConfiguredTargetKey, PlatformInfo> getPlatformInfo(
+      Iterable<ConfiguredTargetKey> platformKeys, Environment env)
+      throws InterruptedException, InvalidPlatformException {
+
+    Map<
+            SkyKey,
+            ValueOrException3<
+                ConfiguredValueCreationException, NoSuchThingException, ActionConflictException>>
+        values =
+            env.getValuesOrThrow(
+                platformKeys,
+                ConfiguredValueCreationException.class,
+                NoSuchThingException.class,
+                ActionConflictException.class);
+    boolean valuesMissing = env.valuesMissing();
+    Map<ConfiguredTargetKey, PlatformInfo> platforms = valuesMissing ? null : new HashMap<>();
+    for (ConfiguredTargetKey key : platformKeys) {
+      PlatformInfo platformInfo = findPlatformInfo(key, values.get(key));
+      if (!valuesMissing && platformInfo != null) {
+        platforms.put(key, platformInfo);
+      }
+    }
+    if (valuesMissing) {
+      return null;
+    }
+
+    return platforms;
+  }
+
+  /**
+   * Returns the {@link PlatformInfo} provider from the {@link ConfiguredTarget} in the {@link
+   * ValueOrException3}, or {@code null} if the {@link ConfiguredTarget} is not present. If the
+   * {@link ConfiguredTarget} does not have a {@link PlatformInfo} provider, a {@link
+   * InvalidPlatformException} is thrown.
+   */
+  @Nullable
+  private static PlatformInfo findPlatformInfo(
+      ConfiguredTargetKey key,
+      ValueOrException3<
+              ConfiguredValueCreationException, NoSuchThingException, ActionConflictException>
+          valueOrException)
+      throws InvalidPlatformException {
+
+    try {
+      ConfiguredTargetValue ctv = (ConfiguredTargetValue) valueOrException.get();
+      if (ctv == null) {
+        return null;
+      }
+
+      ConfiguredTarget configuredTarget = ctv.getConfiguredTarget();
+      PlatformInfo platformInfo = PlatformProviderUtils.platform(configuredTarget);
+      if (platformInfo == null) {
+        throw new InvalidPlatformException(configuredTarget.getLabel());
+      }
+
+      return platformInfo;
+    } catch (ConfiguredValueCreationException e) {
+      throw new InvalidPlatformException(key.getLabel(), e);
+    } catch (NoSuchThingException e) {
+      throw new InvalidPlatformException(key.getLabel(), e);
+    } catch (ActionConflictException e) {
+      throw new InvalidPlatformException(key.getLabel(), e);
+    }
+  }
+
+  /** Exception used when a platform label is not a valid platform. */
+  public static final class InvalidPlatformException extends ToolchainException {
+    InvalidPlatformException(Label label) {
+      super(formatError(label));
+    }
+
+    InvalidPlatformException(Label label, ConfiguredValueCreationException e) {
+      super(formatError(label), e);
+    }
+
+    public InvalidPlatformException(Label label, NoSuchThingException e) {
+      // Just propagate the inner exception, because it's directly actionable.
+      super(e);
+    }
+
+    public InvalidPlatformException(Label label, ActionConflictException e) {
+      super(formatError(label), e);
+    }
+
+    private static String formatError(Label label) {
+      return String.format(
+          "Target %s was referenced as a platform, but does not provide PlatformInfo", label);
+    }
+  }
+}