New class System2 to increase testability of classes that call low-level system methods

5 files changed, 220 insertions, 29 deletions

diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/utils/System2.java b/sonar-plugin-api/src/main/java/org/sonar/api/utils/System2.java
new file mode 100644
index 00000000000..a87dedbdb33
--- /dev/null
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/utils/System2.java
@@ -0,0 +1,102 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2013 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube 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.
+ *
+ * SonarQube 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 org.sonar.api.utils;
+
+import org.apache.commons.lang.SystemUtils;
+
+import javax.annotation.CheckForNull;
+import java.util.Map;
+import java.util.Properties;
+
+/**
+ * Proxy over {@link java.lang.System}. It aims to improve testability of classes
+ * that interact with low-level system methods, for example :
+ *
+ * <pre>
+ * public class MyClass {
+ *   private final System2 system;
+ *
+ *   public MyClass(System2 s) {
+ *     this.system = s;
+ *   }
+ *
+ *   public long xxx() {
+ *     return system.now();
+ *   }
+ *  }
+ *
+ * @Test
+ * public void should_return_xxx() {
+ *   System2 system = mock(System2.class);
+ *   long now = parse("2013-12-25");
+ *   doReturn(now).when(system).now();
+ *   assertThat(new MyClass(system).xxx()).isEqualTo(now);
+ * }
+ * </pre>
+ *
+ * @since 4.2
+ */
+public class System2 {
+
+  public static final System2 INSTANCE = new System2();
+
+  /**
+   * Shortcut for {@link System#currentTimeMillis()}
+   */
+  public long now() {
+    return System.currentTimeMillis();
+  }
+
+  /**
+   * Shortcut for {@link System#getProperties()}
+   */
+  public Properties properties() {
+    return System.getProperties();
+  }
+
+  /**
+   * Shortcut for {@link System#getProperty(String)}
+   */
+  @CheckForNull
+  public String property(String key) {
+    return System.getProperty(key);
+  }
+
+  /**
+   * Shortcut for {@link System#getenv()}
+   */
+  public Map<String, String> envVariables() {
+    return System.getenv();
+  }
+
+  /**
+   * Shortcut for {@link System#getenv(String)}
+   */
+  public String envVariable(String key) {
+    return System.getenv(key);
+  }
+
+  /**
+   * True if this is MS Windows.
+   */
+  public boolean isOsWindows() {
+    return SystemUtils.IS_OS_WINDOWS;
+  }
+}
diff --git a/sonar-plugin-api/src/main/java/org/sonar/api/utils/command/Command.java b/sonar-plugin-api/src/main/java/org/sonar/api/utils/command/Command.java
index c53563ce216..7a39f6a2a7b 100644
--- a/sonar-plugin-api/src/main/java/org/sonar/api/utils/command/Command.java
+++ b/sonar-plugin-api/src/main/java/org/sonar/api/utils/command/Command.java
@@ -26,7 +26,7 @@ import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import org.apache.commons.lang.StringUtils;
-import org.apache.commons.lang.SystemUtils;
+import org.sonar.api.utils.System2;
 
 import java.io.File;
 import java.util.Collections;
@@ -39,13 +39,25 @@ import java.util.Map;
 public class Command {
   private final String executable;
   private final List<String> arguments = Lists.newArrayList();
-  private final Map<String, String> env = Maps.newHashMap(System.getenv());
+  private final Map<String, String> env;
   private File directory;
   private boolean newShell = false;
+  private final System2 system;
 
-  private Command(String executable) {
+  /**
+   * Create a command line without any arguments
+   *
+   * @param executable
+   */
+  public static Command create(String executable) {
+    return new Command(executable, System2.INSTANCE);
+  }
+
+  Command(String executable, System2 system) {
     Preconditions.checkArgument(!StringUtils.isBlank(executable), "Command executable can not be blank");
     this.executable = executable;
+    this.env = Maps.newHashMap(system.envVariables());
+    this.system = system;
   }
 
   public String getExecutable() {
@@ -130,7 +142,7 @@ public class Command {
   List<String> toStrings() {
     ImmutableList.Builder<String> command = ImmutableList.builder();
     if (newShell) {
-      if (SystemUtils.IS_OS_WINDOWS) {
+      if (system.isOsWindows()) {
         command.add("cmd", "/C", "call");
       } else {
         command.add("sh");
@@ -149,13 +161,4 @@ public class Command {
   public String toString() {
     return toCommandLine();
   }
-
-  /**
-   * Create a command line without any arguments
-   *
-   * @param executable
-   */
-  public static Command create(String executable) {
-    return new Command(executable);
-  }
 }
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/utils/System2Test.java b/sonar-plugin-api/src/test/java/org/sonar/api/utils/System2Test.java
new file mode 100644
index 00000000000..b81a065bacc
--- /dev/null
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/utils/System2Test.java
@@ -0,0 +1,72 @@
+/*
+ * SonarQube, open source software quality management tool.
+ * Copyright (C) 2008-2013 SonarSource
+ * mailto:contact AT sonarsource DOT com
+ *
+ * SonarQube 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.
+ *
+ * SonarQube 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 org.sonar.api.utils;
+
+import org.apache.commons.lang.SystemUtils;
+import org.junit.Test;
+
+import java.util.Map;
+import java.util.Properties;
+
+import static org.fest.assertions.Assertions.assertThat;
+import static org.fest.assertions.Fail.fail;
+
+public class System2Test {
+  @Test
+  public void testNow() throws Exception {
+    long start = System.currentTimeMillis();
+    long now = System2.INSTANCE.now();
+    assertThat(now-start).isGreaterThanOrEqualTo(0).isLessThan(3);
+  }
+
+  @Test
+  public void testProperties() throws Exception {
+    Properties expected = System.getProperties();
+    assertThat(System2.INSTANCE.properties()).isNotNull().isEqualTo(expected);
+  }
+
+  @Test
+  public void testProperty() throws Exception {
+    String expected = System.getProperty("java.version");
+    assertThat(System2.INSTANCE.property("java.version")).isNotNull().isEqualTo(expected);
+  }
+
+  @Test
+  public void testEnvVariables() throws Exception {
+    Map<String,String> expected = System.getenv();
+    assertThat(System2.INSTANCE.envVariables()).isNotNull().isEqualTo(expected);
+  }
+
+  @Test
+  public void testEnvVariable() throws Exception {
+    // assume that there's at least one env variable
+    if (System.getenv().isEmpty()) {
+      fail("Test can't succeed because there are no env variables. How is it possible ?");
+    }
+    String key = System.getenv().keySet().iterator().next();
+    String expected = System.getenv(key);
+    assertThat(System2.INSTANCE.envVariable(key)).isNotNull().isEqualTo(expected);
+  }
+
+  @Test
+  public void testIsOsWindows() throws Exception {
+    assertThat(System2.INSTANCE.isOsWindows()).isEqualTo(SystemUtils.IS_OS_WINDOWS);
+  }
+}
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandExecutorTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandExecutorTest.java
index 2c79502b9f2..e898a966819 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandExecutorTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandExecutorTest.java
@@ -27,6 +27,7 @@ import org.junit.Test;
 import org.junit.rules.ExpectedException;
 import org.junit.rules.TemporaryFolder;
 import org.junit.rules.TestName;
+import org.sonar.api.utils.System2;
 
 import java.io.File;
 import java.io.IOException;
@@ -145,7 +146,7 @@ public class CommandExecutorTest {
 
   private static String getScript(String name) throws IOException {
     String filename;
-    if (SystemUtils.IS_OS_WINDOWS) {
+    if (System2.INSTANCE.isOsWindows()) {
       filename = name + ".bat";
     } else {
       filename = name + ".sh";
diff --git a/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandTest.java b/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandTest.java
index db99f370078..296b19859a1 100644
--- a/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandTest.java
+++ b/sonar-plugin-api/src/test/java/org/sonar/api/utils/command/CommandTest.java
@@ -19,15 +19,18 @@
  */
 package org.sonar.api.utils.command;
 
-import org.apache.commons.lang.SystemUtils;
+import com.google.common.collect.ImmutableMap;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
+import org.sonar.api.utils.System2;
 
 import java.io.File;
 import java.util.Arrays;
 
 import static org.fest.assertions.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 
 public class CommandTest {
 
@@ -82,24 +85,34 @@ public class CommandTest {
 
   @Test
   public void override_env_variables() {
-    Command command = Command.create("java");
-    command.setEnvironmentVariable("JAVA_HOME", "/path/to/java");
-    assertThat(command.getEnvironmentVariables().get("JAVA_HOME")).isEqualTo("/path/to/java");
+    System2 system = mock(System2.class);
+    when(system.envVariables()).thenReturn(ImmutableMap.of("JAVA_HOME", "/default/path/to/java"));
+
+    Command command = new Command("java", system);
+    command.setEnvironmentVariable("JAVA_HOME", "/new/path/to/java");
+    assertThat(command.getEnvironmentVariables().get("JAVA_HOME")).isEqualTo("/new/path/to/java");
   }
 
   @Test
-  public void should_use_new_shell() {
-    if (SystemUtils.IS_OS_WINDOWS) {
-      Command command = Command.create("foo.bat");
-      command.setNewShell(true);
-      assertThat(command.toCommandLine()).isEqualTo("cmd /C call foo.bat");
+  public void should_use_cmd_for_new_shell_on_windows() {
+    System2 system = mock(System2.class);
+    when(system.isOsWindows()).thenReturn(true);
+    Command command = new Command("foo.bat", system);
+    command.setNewShell(true);
+    assertThat(command.toCommandLine()).isEqualTo("cmd /C call foo.bat");
       assertThat(command.isNewShell()).isTrue();
-    } else {
-      Command command = Command.create("foo.sh");
-      command.setNewShell(true);
-      assertThat(command.toCommandLine()).isEqualTo("sh foo.sh");
-      assertThat(command.isNewShell()).isTrue();
-    }
+
+  }
+
+  @Test
+  public void should_use_sh_for_new_shell_on_unix() {
+    System2 system = mock(System2.class);
+    when(system.isOsWindows()).thenReturn(false);
+    Command command = new Command("foo.sh", system);
+
+    command.setNewShell(true);
+    assertThat(command.toCommandLine()).isEqualTo("sh foo.sh");
+    assertThat(command.isNewShell()).isTrue();
   }
 
   @Test