1 files changed, 141 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/rules/test/TestLogHelper.java b/src/main/java/com/google/devtools/build/lib/rules/test/TestLogHelper.java
new file mode 100644
index 0000000000..462c24ce6c
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/test/TestLogHelper.java
@@ -0,0 +1,141 @@
+// 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.rules.test;
+
+import com.google.common.io.ByteStreams;
+import com.google.devtools.build.lib.rules.test.TestStrategy.TestOutputFormat;
+import com.google.devtools.build.lib.vfs.Path;
+
+import java.io.BufferedOutputStream;
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PrintStream;
+
+/**
+ * A helper class for test log handling. It determines whether the test log should
+ * be output and formats the test log for console display.
+ */
+public class TestLogHelper {
+
+  public static final String HEADER_DELIMITER =
+    "-----------------------------------------------------------------------------";
+
+  /**
+   * Determines whether the test log should be output from the current outputMode
+   * and whether the test has passed or not.
+   */
+  public static boolean shouldOutputTestLog(TestOutputFormat outputMode, boolean hasPassed) {
+    return (outputMode == TestOutputFormat.ALL) ||
+      (!hasPassed && (outputMode == TestOutputFormat.ERRORS));
+  }
+
+  /**
+   * Reads the contents of the test log from the provided testOutput file, adds
+   * header and footer and returns the result.
+   * This method also looks for a header delimiter and cuts off the text before it,
+   * except if the header is 50 lines or longer.
+   */
+  public static void writeTestLog(Path testOutput, String testName, OutputStream out)
+      throws IOException {
+    InputStream input = null;
+    PrintStream printOut = new PrintStream(new BufferedOutputStream(out));
+    try {
+      final String outputHeader =
+          "==================== Test output for " + testName + ":";
+      final String outputFooter =
+          "================================================================================";
+
+      printOut.println(outputHeader);
+      printOut.flush();
+
+      input = testOutput.getInputStream();
+      FilterTestHeaderOutputStream filteringOutputStream = getHeaderFilteringOutputStream(printOut);
+      ByteStreams.copy(input, filteringOutputStream);
+
+      if (!filteringOutputStream.foundHeader()) {
+        InputStream inputAgain = testOutput.getInputStream();
+        try {
+          ByteStreams.copy(inputAgain, out);
+        } finally {
+          inputAgain.close();
+        }
+      }
+
+      printOut.println(outputFooter);
+    } finally {
+      printOut.flush();
+      if (input != null) {
+        input.close();
+      }
+    }
+  }
+
+  /**
+   * Returns an output stream that doesn't write to original until it
+   * sees HEADER_DELIMITER by itself on a line.
+   */
+  public static FilterTestHeaderOutputStream getHeaderFilteringOutputStream(OutputStream original) {
+    return new FilterTestHeaderOutputStream(original);
+  }
+
+  private TestLogHelper() {
+    // Prevent Java from creating a public constructor.
+  }
+
+  /**
+   * Use this class to filter the streaming output of a test until we see the
+   * header delimiter.
+   */
+  public static class FilterTestHeaderOutputStream extends FilterOutputStream {
+
+    private boolean seenDelimiter = false;
+    private StringBuilder lineBuilder = new StringBuilder();
+
+    private static final int NEWLINE = '\n';
+
+    public FilterTestHeaderOutputStream(OutputStream out) {
+      super(out);
+    }
+
+    @Override
+    public void write(int b) throws IOException {
+      if (seenDelimiter) {
+        out.write(b);
+      } else if (b == NEWLINE) {
+        String line = lineBuilder.toString();
+        lineBuilder = new StringBuilder();
+        if (line.equals(TestLogHelper.HEADER_DELIMITER)) {
+          seenDelimiter = true;
+        }
+      } else if (lineBuilder.length() <= TestLogHelper.HEADER_DELIMITER.length()) {
+        lineBuilder.append((char) b);
+      }
+    }
+
+    @Override
+    public void write(byte b[], int off, int len) throws IOException {
+      if (seenDelimiter) {
+        out.write(b, off, len);
+      } else {
+        super.write(b, off, len);
+      }
+    }
+
+    public boolean foundHeader() {
+      return seenDelimiter;
+    }
+  }
+}