Search for Test classes within the classpath used by the current classloader, instead of the system classpath. (2nd Attempt)

Windows tests passed on Jenkins with this patch:
http://ci.bazel.io/job/Gerrit-bazel-tests/380/,
https://bazel-review.googlesource.com/c/8833

--
PiperOrigin-RevId: 147483103
MOS_MIGRATED_REVID=147483103

1 files changed, 14 insertions, 10 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/testutil/Classpath.java b/src/test/java/com/google/devtools/build/lib/testutil/Classpath.java
index 812951396d..059ef6f1c3 100644
--- a/src/test/java/com/google/devtools/build/lib/testutil/Classpath.java
+++ b/src/test/java/com/google/devtools/build/lib/testutil/Classpath.java
@@ -18,6 +18,8 @@ import java.io.File;
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.net.URL;
+import java.net.URLClassLoader;
 import java.nio.file.Paths;
 import java.util.Enumeration;
 import java.util.LinkedHashSet;
@@ -26,7 +28,6 @@ import java.util.TreeSet;
 import java.util.jar.Attributes;
 import java.util.jar.JarFile;
 import java.util.jar.Manifest;
-import java.util.regex.Pattern;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 
@@ -140,20 +141,23 @@ final class Classpath {
   }
 
   /**
-   * Gets the class path from the System Property "java.class.path" and splits it up into the
-   * individual elements.
-   *
-   * <p>Bazel creates a classpath jar when the class path length exceeds command line length limit,
-   * read the class path value from its manifest file if it's a classpath jar.
+   * Gets the classpath from current classloader.
    */
   private static Set<String> getClassPath() {
-    String classPath = System.getProperty("java.class.path");
-    String separator = System.getProperty("path.separator", ":");
-    String[] classPaths = classPath.split(Pattern.quote(separator));
+    ClassLoader classloader = Classpath.class.getClassLoader();
+    if (!(classloader instanceof URLClassLoader)) {
+      throw new IllegalStateException("Unable to find classes to test, since Test Suite class is "
+          + "loaded by an unsupported Classloader.");
+    }
+
     Set<String> completeClassPaths = new TreeSet<>();
-    for (String entryName : classPaths) {
+    URL[] urls = ((URLClassLoader) classloader).getURLs();
+    for (URL url : urls) {
+      String entryName = url.getPath();
       completeClassPaths.add(entryName);
       if (entryName.endsWith("-classpath.jar")) {
+        // Bazel creates a classpath jar when the class path length exceeds command line length
+        // limit, read the class path value from its manifest file if it's a classpath jar.
         File classPathEntry = new File(entryName);
         if (classPathEntry.exists() && classPathEntry.isFile()) {
           try {