Fixes classLocation and classfileLocation

This fixes classLocation family of methods and classfileLocation that were broken in sbt#181.
eed3si9n · Oct 4, 2018 · 7d36919 · 7d36919
1 parent 9d67949
commit 7d36919
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Showing 3 changed files with 155 additions and 4 deletions.
diff --git a/build.sbt b/build.sbt
@@ -34,6 +34,9 @@ val io = (project in file("io"))
       Vector(scalaCompiler.value % Test, scalaCheck % Test, scalatest.value % Test)
     } ++ Vector(swovalFiles),
     libraryDependencies ++= Seq(jna, jnaPlatform),
+
+    Test / fork := true,
+
     sourceManaged in (Compile, generateContrabands) := baseDirectory.value / "src" / "main" / "contraband-scala",
     initialCommands in console += "\nimport sbt.io._, syntax._",
     mimaPreviousArtifacts := (CrossVersion partialVersion scalaVersion.value match {

diff --git a/io/src/main/scala/sbt/io/IO.scala b/io/src/main/scala/sbt/io/IO.scala
@@ -62,7 +62,7 @@ object IO {
    * Note that Java standard library classes typically do not have a location associated with them.
    */
   def classLocationPath(cl: Class[_]): NioPath = {
-    val u = classfileLocation(cl)
+    val u = classLocation(cl)
     val p = u.getProtocol match {
       case FileScheme => Option(toFile(u).toPath)
       case "jar"      => urlAsFile(u) map { _.toPath }
@@ -85,7 +85,7 @@ object IO {
    * Note that Java standard library classes typically do not have a location associated with them.
    */
   def classLocationFileOption(cl: Class[_]): Option[File] = {
-    val u = classfileLocation(cl)
+    val u = classLocation(cl)
     urlAsFile(u)
   }
 
@@ -118,6 +118,59 @@ object IO {
     "1.3.0")
   def classLocationFile[T](implicit mf: SManifest[T]): File = classLocationFile(mf.runtimeClass)
 
+  /**
+   * Returns the URL to the directory or the JAR file containing the class file `cl`.
+   * If the location cannot be determined or it is not a file, an error is generated.
+   * Note that Java standard library classes typically do not have a location associated with them.
+   */
+  def classLocation(cl: Class[_]): URL = {
+    def localcl: Option[URL] =
+      Option(cl.getProtectionDomain.getCodeSource) flatMap { codeSource =>
+        Option(codeSource.getLocation)
+      }
+    // This assumes that classes without code sources are System classes, and thus located in jars.
+    // It returns a URL that looks like jar:file:/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/rt.jar!/java/lang/Integer.class
+    val clsfile = s"${cl.getName.replace('.', '/')}.class"
+    def syscl: Option[URL] =
+      Option(ClassLoader.getSystemClassLoader) flatMap { classLoader =>
+        Option(classLoader.getResource(clsfile))
+      }
+    try {
+      localcl
+        .orElse(syscl)
+        .map(url =>
+          url.getProtocol match {
+            case "jar" =>
+              val path = url.getPath
+              val end = path.indexOf('!')
+              new URL(
+                if (end == -1) path
+                else path.substring(0, end))
+            case "jrt" =>
+              val path = url.getPath
+              val end = path.indexOf('/', 1)
+              new URL("jrt",
+                      null,
+                      if (end == -1) path
+                      else path.substring(0, end))
+            case _ => url
+        })
+        .getOrElse(sys.error("No class location for " + cl))
+    } catch {
+      case NonFatal(e) =>
+        e.printStackTrace()
+        throw e
+    }
+  }
+
+  /**
+   * Returns the URL to the directory or the JAR file containing the class file `cl`.
+   * If the location cannot be determined or it is not a file, an error is generated.
+   * Note that Java standard library classes typically do not have a location associated with them.
+   */
+  def classLocation[A](implicit mf: SManifest[A]): URL =
+    classLocation(mf.runtimeClass)
+
   /**
    * Returns a URL for the classfile containing the given class file for type `T` (as determined by an implicit Manifest).
    * If the location cannot be determined, an error is generated.
@@ -131,8 +184,8 @@ object IO {
   def classfileLocation(cl: Class[_]): URL = {
     val clsfile = s"${cl.getName.replace('.', '/')}.class"
     def localcl: Option[URL] =
-      Option(cl.getProtectionDomain.getCodeSource) flatMap { codeSource =>
-        Option(codeSource.getLocation)
+      Option(cl.getClassLoader) flatMap { classLoader =>
+        Option(classLoader.getResource(clsfile))
       }
     def syscl: Option[URL] =
       Option(ClassLoader.getSystemClassLoader) flatMap { classLoader =>

diff --git a/io/src/test/scala/sbt/io/IOSpec.scala b/io/src/test/scala/sbt/io/IOSpec.scala
@@ -70,6 +70,101 @@ class IOSpec extends FunSuite {
     assert(IO.getModifiedTimeOrZero(file("/not/existing/path")) == 0L)
   }
 
+  // classLocation -----------
+
+  test("classLocation[Integer] should return a URL pointing to the rt.jar or java.base") {
+    val u = IO.classLocation[java.lang.Integer]
+    assert(
+      (u.toString == "jrt:/java.base") ||
+        (u.toString.startsWith("file:") && u.toString.endsWith("rt.jar") && IO.asFile(u).isFile))
+  }
+
+  test(
+    "classLocation[AbstractMap.SimpleEntry] should return a URL pointing to the rt.jar or java.base") {
+    val u = IO.classLocation[java.util.AbstractMap.SimpleEntry[String, String]]
+    assert(
+      (u.toString == "jrt:/java.base") ||
+        (u.toString.startsWith("file:") && u.toString.endsWith("rt.jar") && IO.asFile(u).isFile))
+  }
+
+  test("classLocation[this.type] should return a URL pointing to a directory") {
+    val u = IO.classLocation[this.type]
+    assert(IO.asFile(u).isDirectory)
+  }
+
+  // classLocationPath -----------
+
+  test("classLocationPath[Integer] should return NIO path pointing to the rt.jar or java.base") {
+    val p = IO.classLocationPath[java.lang.Integer]
+    assert(
+      ((p.toString == "/modules/java.base") && (p.getFileSystem.toString == "jrt:/"))
+        || (p.toString.endsWith("rt.jar") && p.toFile.isFile)
+    )
+  }
+
+  test(
+    "classLocationPath[AbstractMap.SimpleEntry] should return NIO path pointing to the rt.jar or java.base") {
+    val p = IO.classLocationPath[java.util.AbstractMap.SimpleEntry[String, String]]
+    assert(
+      ((p.toString == "/modules/java.base") && (p.getFileSystem.toString == "jrt:/"))
+        || (p.toString.endsWith("rt.jar") && p.toFile.isFile)
+    )
+  }
+
+  test("classLocationPath[this.type] should return NIO path pointing to a directory") {
+    val p = IO.classLocationPath[this.type]
+    assert(p.toFile.isDirectory)
+  }
+
+  // classLocationFileOption -----------
+
+  test("classLocationFileOption[Integer] should return File pointing to the rt.jar or None") {
+    val opt = IO.classLocationFileOption[java.lang.Integer]
+    assert(
+      opt match {
+        case Some(x) => x.getName == "rt.jar"
+        case None    => true
+      }
+    )
+  }
+
+  test(
+    "classLocationFileOption[AbstractMap.SimpleEntry] should return File pointing to the rt.jar or None") {
+    val opt = IO.classLocationFileOption[java.util.AbstractMap.SimpleEntry[String, String]]
+    assert(
+      opt match {
+        case Some(x) => x.getName == "rt.jar"
+        case None    => true
+      }
+    )
+  }
+
+  test("classLocationFileOption[this.type] should return File pointing to a directory") {
+    val opt = IO.classLocationFileOption[this.type]
+    assert(opt.get.isDirectory)
+  }
+
+  // classfileLocation -----------
+
+  test("classfileLocation[Integer] should return a URL pointing to *.class") {
+    val s = IO.classfileLocation[java.lang.Integer].toString
+    assert(
+      (s == "jrt:/java.base/java/lang/Integer.class") ||
+        (s.startsWith("jar:file:") && s.endsWith("!/java/lang/Integer.class")))
+  }
+
+  test("classfileLocation[AbstractMap.SimpleEntry] should return a URL pointing to *.class") {
+    val s = IO.classfileLocation[java.util.AbstractMap.SimpleEntry[String, String]].toString
+    assert(
+      (s == "jrt:/java.base/java/util/AbstractMap$SimpleEntry.class") ||
+        (s.startsWith("jar:file:") && s.endsWith("!/java/util/AbstractMap$SimpleEntry.class")))
+  }
+
+  test("classfileLocation[this.type] should return a URL pointing to *.class") {
+    val s = IO.classfileLocation[this.type].toString
+    assert(s.startsWith("file:") && s.endsWith("/sbt/io/IOSpec.class"))
+  }
+
   def normalizeForWindows(s: String): String = {
     s.replaceAllLiterally("""\""", "/")
   }