Implement smart negation for target pattern sequences

This change uses the types of target patterns, and the order they
appear in the sequence, to construct a more efficiently processable
sequence of target pattern keys. Redundant patterns are eliminated and
negated TargetsBelowDirectory patterns are excluded from higher-up
positive patterns.

--
MOS_MIGRATED_REVID=94909360

1 files changed, 40 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SignedPattern.java b/src/main/java/com/google/devtools/build/lib/skyframe/SignedPattern.java
new file mode 100644
index 0000000000..034f35e5cc
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SignedPattern.java
@@ -0,0 +1,40 @@
+// Copyright 2015 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.skyframe;
+
+import com.google.devtools.build.lib.cmdline.TargetPattern;
+
+final class SignedPattern {
+
+  private final boolean positive;
+  private final TargetPattern pattern;
+
+  SignedPattern(boolean positive, TargetPattern pattern) {
+    this.positive = positive;
+    this.pattern = pattern;
+  }
+
+  boolean isPositive() {
+    return positive;
+  }
+
+  TargetPattern getPattern() {
+    return pattern;
+  }
+
+  @Override
+  public String toString() {
+    return (positive ? "" : "-") + pattern.getOriginalPattern();
+  }
+}