1 files changed, 97 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/packages/EnumFilterConverter.java b/src/main/java/com/google/devtools/build/lib/packages/EnumFilterConverter.java
new file mode 100644
index 0000000000..31242e35fe
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+++ b/src/main/java/com/google/devtools/build/lib/packages/EnumFilterConverter.java
@@ -0,0 +1,97 @@
+// Copyright 2014 Google Inc. 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.packages;
+
+import com.google.devtools.build.lib.util.StringUtil;
+import com.google.devtools.common.options.Converter;
+import com.google.devtools.common.options.OptionsParsingException;
+
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.LinkedHashSet;
+import java.util.Set;
+
+/**
+ * Converter that translates a string of the form "value1,value2,-value3,value4"
+ * into a corresponding set of allowed Enum values.
+ *
+ * <p>Values preceded by '-' are excluded from this set. So "value1,-value2,value3"
+ * translates to the set [EnumType.value1, EnumType.value3].
+ *
+ * <p>If *all* values are exclusions (e.g. "-value1,-value2,-value3"), the returned
+ * set contains all values for the Enum type *except* those specified.
+ */
+class EnumFilterConverter<E extends Enum<E>> implements Converter<Set<E>> {
+
+  private final Set<String> allowedValues = new LinkedHashSet<>();
+  private final Class<E> typeClass;
+  private final String prettyEnumName;
+
+  /**
+   * Constructor.
+   *
+   * @param typeClass this should be E.class (Java generics can't infer that directly)
+   * @param userFriendlyName a user-friendly description of this enum type
+   */
+  public EnumFilterConverter(Class<E> typeClass, String userFriendlyName) {
+    this.typeClass = typeClass;
+    this.prettyEnumName = userFriendlyName;
+    for (E value : EnumSet.allOf(typeClass)) {
+      allowedValues.add(value.name());
+    }
+  }
+
+  /**
+   * Returns the set of allowed values for the option.
+   *
+   * Implements {@link #convert(String)}.
+   */
+  @Override
+  public Set<E> convert(String input) throws OptionsParsingException {
+    if (input.equals("")) {
+      return Collections.emptySet();
+    }
+    EnumSet<E> includedSet = EnumSet.noneOf(typeClass);
+    EnumSet<E> excludedSet = EnumSet.noneOf(typeClass);
+    for (String value : input.split(",", -1)) {
+      boolean excludeFlag = value.startsWith("-");
+      String s = (excludeFlag ? value.substring(1) : value).toUpperCase();
+      if (!allowedValues.contains(s)) {
+        throw new OptionsParsingException("Invalid " + prettyEnumName + " filter '" + value +
+            "' in the input '" + input + "'");
+      }
+      (excludeFlag ? excludedSet : includedSet).add(E.valueOf(typeClass, s));
+    }
+    if (includedSet.isEmpty()) {
+      includedSet = EnumSet.complementOf(excludedSet);
+    } else {
+      includedSet.removeAll(excludedSet);
+    }
+    if (includedSet.isEmpty()) {
+      throw new OptionsParsingException(
+          Character.toUpperCase(prettyEnumName.charAt(0)) + prettyEnumName.substring(1) +
+          " filter '" + input + "' definition cannot match any tests");
+    }
+    return includedSet;
+  }
+
+  /**
+   * Implements {@link #getTypeDescription()}.
+   */
+  @Override
+  public final String getTypeDescription() {
+    return "comma-separated list of values: "
+        + StringUtil.joinEnglishList(allowedValues).toLowerCase();
+  }
+}