1 files changed, 91 insertions, 0 deletions
diff --git a/src/test/java/testutils/LogTester.java b/src/test/java/testutils/LogTester.java
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+++ b/src/test/java/testutils/LogTester.java
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+/*
+ * SonarScanner CLI
+ * Copyright (C) 2011-2024 SonarSource SA
+ * mailto:info AT sonarsource DOT com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+package testutils;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.classic.spi.LoggingEvent;
+import java.util.List;
+import org.junit.jupiter.api.extension.AfterEachCallback;
+import org.junit.jupiter.api.extension.BeforeEachCallback;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.slf4j.LoggerFactory;
+import org.slf4j.event.Level;
+
+public class LogTester implements BeforeEachCallback, AfterEachCallback {
+
+  private final ConcurrentListAppender<ILoggingEvent> listAppender = new ConcurrentListAppender<>();
+
+  public LogTester() {
+    setLevel(Level.INFO);
+  }
+
+  /**
+   * Change log level.
+   * By default, INFO logs are enabled when LogTester is started.
+   */
+  public LogTester setLevel(Level level) {
+    getRootLogger().setLevel(ch.qos.logback.classic.Level.fromLocationAwareLoggerInteger(level.toInt()));
+    return this;
+  }
+
+  private static ch.qos.logback.classic.Logger getRootLogger() {
+    return (ch.qos.logback.classic.Logger) LoggerFactory.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);
+  }
+
+  /**
+   * Logs in chronological order (item at index 0 is the oldest one)
+   */
+  public List<String> logs() {
+    return listAppender.list.stream().map(e -> (LoggingEvent) e)
+      .map(LoggingEvent::getFormattedMessage)
+      .toList();
+  }
+
+  /**
+   * Logs in chronological order (item at index 0 is the oldest one) for
+   * a given level
+   */
+  public List<String> logs(Level level) {
+    return listAppender.list.stream().map(e -> (LoggingEvent) e)
+      .filter(e -> e.getLevel().equals(ch.qos.logback.classic.Level.fromLocationAwareLoggerInteger(level.toInt())))
+      .map(LoggingEvent::getFormattedMessage)
+      .toList();
+  }
+
+  public LogTester clear() {
+    listAppender.list.clear();
+    return this;
+  }
+
+  @Override
+  public void beforeEach(ExtensionContext context) throws Exception {
+    getRootLogger().addAppender(listAppender);
+    listAppender.start();
+  }
+
+  @Override
+  public void afterEach(ExtensionContext context) throws Exception {
+    listAppender.stop();
+    listAppender.list.clear();
+    getRootLogger().detachAppender(listAppender);
+    // Reset the level for following-up test suites
+    setLevel(Level.INFO);
+  }
+}