diff --git a/src/test/java/com/google/devtools/build/lib/windows/WindowsProcessesTest.java b/src/test/java/com/google/devtools/build/lib/windows/WindowsProcessesTest.java
index 91e4fe4..e1b4ec7 100644
--- a/src/test/java/com/google/devtools/build/lib/windows/WindowsProcessesTest.java
+++ b/src/test/java/com/google/devtools/build/lib/windows/WindowsProcessesTest.java
@@ -18,7 +18,8 @@
 import static java.nio.charset.StandardCharsets.UTF_16LE;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
-import com.google.common.collect.ImmutableList;
+import com.google.common.base.Joiner;
+import com.google.devtools.build.lib.shell.ShellUtils;
 import com.google.devtools.build.lib.testutil.TestSpec;
 import com.google.devtools.build.lib.util.OS;
 import com.google.devtools.build.lib.windows.jni.WindowsProcesses;
@@ -65,16 +66,26 @@
     }
   }
 
+  private static List<String> quoteArgs(List<String> argv, String... args) {
+    for (String arg : args) {
+      argv.add(ShellUtils.windowsEscapeArg(arg));
+    }
+    return argv;
+  }
+
+  private static List<String> quoteArgs(String... args) {
+    List<String> argv = new ArrayList<>();
+    return quoteArgs(argv, args);
+  }
+
   private String mockArgs(String... args) {
     List<String> argv = new ArrayList<>();
 
     argv.add("-jar");
     argv.add(mockSubprocess);
-    for (String arg : args) {
-      argv.add(arg);
-    }
+    quoteArgs(argv, args);
 
-    return WindowsProcesses.quoteCommandLine(argv);
+    return Joiner.on(" ").join(argv);
   }
 
   private void assertNoProcessError() throws Exception {
@@ -87,35 +98,32 @@
 
   @Test
   public void testDoesNotQuoteSimpleArg() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", "a"))).isEqualTo("x a");
+    assertThat(quoteArgs("x", "a")).containsExactly("x", "a").inOrder();
   }
 
   @Test
   public void testQuotesEmptyArg() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", ""))).isEqualTo("x \"\"");
+    assertThat(quoteArgs("x", "")).containsExactly("x", "\"\"").inOrder();
   }
 
   @Test
   public void testQuotesArgWithSpace() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", "a b")))
-        .isEqualTo("x \"a b\"");
+    assertThat(quoteArgs("x", "a b")).containsExactly("x", "\"a b\"").inOrder();
   }
 
   @Test
   public void testDoesNotQuoteArgWithBackslash() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", "a\\b")))
-        .isEqualTo("x a\\b");
+    assertThat(quoteArgs("x", "a\\b")).containsExactly("x", "a\\b").inOrder();
   }
 
   @Test
   public void testDoesNotQuoteArgWithSingleQuote() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", "a'b"))).isEqualTo("x a'b");
+    assertThat(quoteArgs("x", "a'b")).containsExactly("x", "a'b").inOrder();
   }
 
   @Test
-  public void testDoesNotQuoteArgWithDoubleQuote() throws Exception {
-    assertThat(WindowsProcesses.quoteCommandLine(ImmutableList.of("x", "a\"b")))
-        .isEqualTo("x a\\\"b");
+  public void testQuotesArgWithDoubleQuote() throws Exception {
+    assertThat(quoteArgs("x", "a\"b", "y")).containsExactly("x", "\"a\\\"b\"", "y").inOrder();
   }
 
   @Test
diff --git a/src/test/java/com/google/devtools/build/lib/windows/WindowsSubprocessTest.java b/src/test/java/com/google/devtools/build/lib/windows/WindowsSubprocessTest.java
index d392230..77ccd85 100644
--- a/src/test/java/com/google/devtools/build/lib/windows/WindowsSubprocessTest.java
+++ b/src/test/java/com/google/devtools/build/lib/windows/WindowsSubprocessTest.java
@@ -17,17 +17,14 @@
 import static com.google.common.truth.Truth.assertThat;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
-import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.shell.ShellUtils;
 import com.google.devtools.build.lib.shell.Subprocess;
 import com.google.devtools.build.lib.shell.SubprocessBuilder;
 import com.google.devtools.build.lib.testutil.TestSpec;
 import com.google.devtools.build.lib.util.OS;
-import com.google.devtools.build.lib.windows.jni.WindowsProcesses;
 import com.google.devtools.build.runfiles.Runfiles;
 import java.io.File;
-import java.util.function.Function;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -65,9 +62,9 @@
     }
   }
 
-  private void assertSystemRootIsSetByDefault(boolean windowsStyleArgEscaping) throws Exception {
-    SubprocessBuilder subprocessBuilder =
-        new SubprocessBuilder(new WindowsSubprocessFactory(windowsStyleArgEscaping));
+  @Test
+  public void testSystemRootIsSetByDefault() throws Exception {
+    SubprocessBuilder subprocessBuilder = new SubprocessBuilder(WindowsSubprocessFactory.INSTANCE);
     subprocessBuilder.setWorkingDirectory(new File("."));
     subprocessBuilder.setArgv(mockBinary, "-jar", mockSubprocess, "O$SYSTEMROOT");
     process = subprocessBuilder.start();
@@ -80,18 +77,8 @@
   }
 
   @Test
-  public void testSystemRootIsSetByDefaultNoWindowsStyleArgEscaping() throws Exception {
-    assertSystemRootIsSetByDefault(false);
-  }
-
-  @Test
-  public void testSystemRootIsSetByDefaultWithWindowsStyleArgEscaping() throws Exception {
-    assertSystemRootIsSetByDefault(true);
-  }
-
-  private void assertSystemDriveIsSetByDefault(boolean windowsStyleArgEscaping) throws Exception {
-    SubprocessBuilder subprocessBuilder =
-        new SubprocessBuilder(new WindowsSubprocessFactory(windowsStyleArgEscaping));
+  public void testSystemDriveIsSetByDefault() throws Exception {
+    SubprocessBuilder subprocessBuilder = new SubprocessBuilder(WindowsSubprocessFactory.INSTANCE);
     subprocessBuilder.setWorkingDirectory(new File("."));
     subprocessBuilder.setArgv(mockBinary, "-jar", mockSubprocess, "O$SYSTEMDRIVE");
     process = subprocessBuilder.start();
@@ -104,18 +91,8 @@
   }
 
   @Test
-  public void testSystemDriveIsSetByDefaultNoWindowsStyleArgEscaping() throws Exception {
-    assertSystemDriveIsSetByDefault(false);
-  }
-
-  @Test
-  public void testSystemDriveIsSetByDefaultWithWindowsStyleArgEscaping() throws Exception {
-    assertSystemDriveIsSetByDefault(true);
-  }
-
-  private void assertSystemRootIsSet(boolean windowsStyleArgEscaping) throws Exception {
-    SubprocessBuilder subprocessBuilder =
-        new SubprocessBuilder(new WindowsSubprocessFactory(windowsStyleArgEscaping));
+  public void testSystemRootIsSet() throws Exception {
+    SubprocessBuilder subprocessBuilder = new SubprocessBuilder(WindowsSubprocessFactory.INSTANCE);
     subprocessBuilder.setWorkingDirectory(new File("."));
     subprocessBuilder.setArgv(mockBinary, "-jar", mockSubprocess, "O$SYSTEMROOT");
     // Case shouldn't matter on Windows
@@ -130,18 +107,8 @@
   }
 
   @Test
-  public void testSystemRootIsSetNoWindowsStyleArgEscaping() throws Exception {
-    assertSystemRootIsSet(false);
-  }
-
-  @Test
-  public void testSystemRootIsSetWithWindowsStyleArgEscaping() throws Exception {
-    assertSystemRootIsSet(true);
-  }
-
-  private void assertSystemDriveIsSet(boolean windowsStyleArgEscaping) throws Exception {
-    SubprocessBuilder subprocessBuilder =
-        new SubprocessBuilder(new WindowsSubprocessFactory(windowsStyleArgEscaping));
+  public void testSystemDriveIsSet() throws Exception {
+    SubprocessBuilder subprocessBuilder = new SubprocessBuilder(WindowsSubprocessFactory.INSTANCE);
     subprocessBuilder.setWorkingDirectory(new File("."));
     subprocessBuilder.setArgv(mockBinary, "-jar", mockSubprocess, "O$SYSTEMDRIVE");
     // Case shouldn't matter on Windows
@@ -155,16 +122,6 @@
     assertThat(new String(buf, UTF_8).trim()).isEqualTo("X:");
   }
 
-  @Test
-  public void testSystemDriveIsSetNoWindowsStyleArgEscaping() throws Exception {
-    assertSystemDriveIsSet(false);
-  }
-
-  @Test
-  public void testSystemDriveIsSetWithWindowsStyleArgEscaping() throws Exception {
-    assertSystemDriveIsSet(true);
-  }
-
   /**
    * An argument and its command-line-escaped counterpart.
    *
@@ -181,9 +138,7 @@
   };
 
   /** Asserts that a subprocess correctly receives command line arguments. */
-  private void assertSubprocessReceivesArgsAsIntended(
-      boolean windowsStyleArgEscaping, Function<String, String> escaper, ArgPair... args)
-      throws Exception {
+  private void assertSubprocessReceivesArgsAsIntended(ArgPair... args) throws Exception {
     // Look up the path of the printarg.exe utility.
     String printArgExe =
         runfiles.rlocation("io_bazel/src/test/java/com/google/devtools/build/lib/printarg.exe");
@@ -191,11 +146,11 @@
 
     for (ArgPair arg : args) {
       // Assert that the command-line encoding logic works as intended.
-      assertThat(escaper.apply(arg.original)).isEqualTo(arg.escaped);
+      assertThat(ShellUtils.windowsEscapeArg(arg.original)).isEqualTo(arg.escaped);
 
       // Create a separate subprocess just for this argument.
       SubprocessBuilder subprocessBuilder =
-          new SubprocessBuilder(new WindowsSubprocessFactory(windowsStyleArgEscaping));
+          new SubprocessBuilder(WindowsSubprocessFactory.INSTANCE);
       subprocessBuilder.setWorkingDirectory(new File("."));
       subprocessBuilder.setArgv(printArgExe, arg.original);
       process = subprocessBuilder.start();
@@ -212,25 +167,8 @@
   }
 
   @Test
-  public void testSubprocessReceivesArgsAsIntendedNoWindowsStyleArgEscaping() throws Exception {
+  public void testSubprocessReceivesArgsAsIntended() throws Exception {
     assertSubprocessReceivesArgsAsIntended(
-        false,
-        x -> WindowsProcesses.quoteCommandLine(ImmutableList.of(x)),
-        new ArgPair("", "\"\""),
-        new ArgPair(" ", "\" \""),
-        new ArgPair("foo", "foo"),
-        new ArgPair("foo\\bar", "foo\\bar"),
-        new ArgPair("foo bar", "\"foo bar\""));
-    // TODO(laszlocsomor): the escaping logic in WindowsProcesses.quoteCommandLine is wrong, because
-    // it fails to properly escape things like a single backslash followed by a quote, e.g. a\"b
-    // Fix the escaping logic and add more test here.
-  }
-
-  @Test
-  public void testSubprocessReceivesArgsAsIntendedWithWindowsStyleArgEscaping() throws Exception {
-    assertSubprocessReceivesArgsAsIntended(
-        true,
-        x -> ShellUtils.windowsEscapeArg(x),
         new ArgPair("", "\"\""),
         new ArgPair(" ", "\" \""),
         new ArgPair("\"", "\"\\\"\""),