SONAR-21972 Fix tests to not depend on the operating system's locale

build.gradle

     jvmArgs '-Dfile.encoding=UTF8'
     maxHeapSize = '1500m'
     systemProperty 'java.awt.headless', true
+    // Some tests are asserting on localized messages or dates
+    systemProperty 'user.language', 'en'
+    systemProperty 'user.country', 'US'
+    environment 'LANGUAGE', 'en_US'
     testLogging {
       events "skipped", "failed" // verbose log for failed and skipped tests (by default the name of the tests are not logged)
       exceptionFormat 'full' // log the full stack trace (default is the 1st line of the stack trace)

sonar-scanner-engine/src/main/java/org/sonar/scm/git/ProcessWrapperFactory.java

 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.nio.file.Path;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Scanner;
 import java.util.function.Consumer;
 import javax.annotation.Nullable;
   }
 
   public ProcessWrapper create(@Nullable Path baseDir, Consumer<String> stdOutLineConsumer, String... command) {
-    return new ProcessWrapper(baseDir, stdOutLineConsumer, command);
+    return new ProcessWrapper(baseDir, stdOutLineConsumer, Map.of(), command);
+  }
+
+  public ProcessWrapper create(@Nullable Path baseDir, Consumer<String> stdOutLineConsumer, Map<String, String> envVariables, String... command) {
+    return new ProcessWrapper(baseDir, stdOutLineConsumer, envVariables, command);
   }
 
   static class ProcessWrapper {
     private final Path baseDir;
     private final Consumer<String> stdOutLineConsumer;
     private final String[] command;
+    private final Map<String, String> envVariables = new HashMap<>();
 
-    ProcessWrapper(@Nullable Path baseDir, Consumer<String> stdOutLineConsumer, String... command) {
+    ProcessWrapper(@Nullable Path baseDir, Consumer<String> stdOutLineConsumer, Map<String, String> envVariables, String... command) {
       this.baseDir = baseDir;
       this.stdOutLineConsumer = stdOutLineConsumer;
+      this.envVariables.putAll(envVariables);
       this.command = command;
     }
 
       ProcessBuilder pb = new ProcessBuilder()
         .command(command)
         .directory(baseDir != null ? baseDir.toFile() : null);
+      envVariables.forEach(pb.environment()::put);
 
       Process p = pb.start();
       try {

sonar-scanner-engine/src/test/java/org/sonar/scm/git/ProcessWrapperFactoryTest.java

 package org.sonar.scm.git;
 
 import java.io.IOException;
+import java.util.Map;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
   public void should_log_error_output_in_debug_mode() throws IOException {
     logTester.setLevel(Level.DEBUG);
     var root = temp.newFolder().toPath();
-    var processWrapper = underTest.create(root, v -> {}, "git", "blame");
-    assertThatThrownBy(() -> processWrapper.execute())
+    var processWrapper = underTest.create(root, v -> {}, Map.of("LANG", "en_US"), "git", "blame");
+    assertThatThrownBy(processWrapper::execute)
       .isInstanceOf(IllegalStateException.class);
 
     assertThat(logTester.logs(Level.DEBUG).get(0)).startsWith("fatal:");