Use new asClassPathString method and create FileUtils for classpath

The method asClasspathString is now deprecated. Moreover it's moved
to ClassFileLookup in the case someone was using it in some project
(an alternative classpath also will support it - just in the case).
All its usages existing in Scala sources are changed to
asClassPathString method. The only difference is the name.

Some operations on files or their names are moved from ClassPath to
the newly created FileUtils dedicated to classpath. It will be
possible to reuse them when implementing an alternative classpath
representation. Moreover such allocation-free extension methods like
the one added in this commit will improve the readability.

6 files changed, 88 insertions, 42 deletions

diff --git a/src/compiler/scala/tools/nsc/Global.scala b/src/compiler/scala/tools/nsc/Global.scala
index 430424d0f8..2316fb7ce9 100644
--- a/src/compiler/scala/tools/nsc/Global.scala
+++ b/src/compiler/scala/tools/nsc/Global.scala
@@ -339,11 +339,11 @@ class Global(var currentSettings: Settings, var reporter: Reporter)
     }
   }
 
-  if (settings.verbose || settings.Ylogcp) {
+  if (settings.verbose || settings.Ylogcp)
     reporter.echo(
-      s"[search path for source files: ${classPath.sourcepaths.mkString(",")}]\n"+
-      s"[search path for class files: ${classPath.asClasspathString}")
-  }
+      s"[search path for source files: ${classPath.asSourcePathString}]\n" +
+      s"[search path for class files: ${classPath.asClassPathString}]"
+    )
 
   // The current division between scala.reflect.* and scala.tools.nsc.* is pretty
   // clunky.  It is often difficult to have a setting influence something without having
@@ -882,7 +882,7 @@ class Global(var currentSettings: Settings, var reporter: Reporter)
    */
   def invalidateClassPathEntries(paths: String*): Unit = {
     implicit object ClassPathOrdering extends Ordering[PlatformClassPath] {
-      def compare(a:PlatformClassPath, b:PlatformClassPath) = a.asClasspathString compare b.asClasspathString
+      def compare(a:PlatformClassPath, b:PlatformClassPath) = a.asClassPathString compare b.asClassPathString
     }
     val invalidated, failed = new mutable.ListBuffer[ClassSymbol]
     classPath match {
diff --git a/src/compiler/scala/tools/nsc/classpath/FileUtils.scala b/src/compiler/scala/tools/nsc/classpath/FileUtils.scala
new file mode 100644
index 0000000000..0221454c04
--- /dev/null
+++ b/src/compiler/scala/tools/nsc/classpath/FileUtils.scala
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2014 Contributor. All rights reserved.
+ */
+package scala.tools.nsc.classpath
+
+import java.net.URL
+import scala.reflect.internal.FatalError
+import scala.reflect.io.AbstractFile
+
+/**
+ * Common methods related to files used in the context of classpath
+ */
+object FileUtils {
+  implicit class AbstractFileOps(val file: AbstractFile) extends AnyVal {
+
+    /**
+     * Safe method returning a sequence containing one URL representing this file, when underlying file exists,
+     * and returning given default value in other case
+     */
+    def toURLs(default: => Seq[URL] = Seq.empty): Seq[URL] = if (file.file == null) default else Seq(file.toURL)
+  }
+
+  def stripSourceExtension(fileName: String): String = {
+    if (endsScala(fileName)) stripClassExtension(fileName)
+    else if (endsJava(fileName)) stripJavaExtension(fileName)
+    else throw new FatalError("Unexpected source file ending: " + fileName)
+  }
+
+  def endsClass(fileName: String): Boolean =
+    fileName.length > 6 && fileName.substring(fileName.length - 6) == ".class"
+
+  def endsScalaOrJava(fileName: String): Boolean =
+    endsScala(fileName) || endsJava(fileName)
+
+  def endsJava(fileName: String): Boolean =
+    fileName.length > 5 && fileName.substring(fileName.length - 5) == ".java"
+
+  def endsScala(fileName: String): Boolean =
+    fileName.length > 6 && fileName.substring(fileName.length - 6) == ".scala"
+
+  def stripClassExtension(fileName: String): String =
+    fileName.substring(0, fileName.length - 6) // equivalent of fileName.length - ".class".length
+
+  def stripJavaExtension(fileName: String): String =
+    fileName.substring(0, fileName.length - 5)
+}
diff --git a/src/compiler/scala/tools/nsc/util/ClassFileLookup.scala b/src/compiler/scala/tools/nsc/util/ClassFileLookup.scala
index b36580e6c4..4451651229 100644
--- a/src/compiler/scala/tools/nsc/util/ClassFileLookup.scala
+++ b/src/compiler/scala/tools/nsc/util/ClassFileLookup.scala
@@ -30,6 +30,10 @@ trait ClassFileLookup[T] {
     */
   def asClassPathString: String
 
+  // for compatibility purposes
+  @deprecated("Use asClassPathString instead of this one", "2.11.5")
+  def asClasspathString: String = asClassPathString
+
   /** The whole sourcepath in the form of one String.
     */
   def asSourcePathString: String
diff --git a/src/compiler/scala/tools/nsc/util/ClassPath.scala b/src/compiler/scala/tools/nsc/util/ClassPath.scala
index 6c8bd9a59b..431ad0adf0 100644
--- a/src/compiler/scala/tools/nsc/util/ClassPath.scala
+++ b/src/compiler/scala/tools/nsc/util/ClassPath.scala
@@ -7,16 +7,19 @@
 package scala.tools.nsc
 package util
 
+import io.{ AbstractFile, Directory, File, Jar }
+import java.net.MalformedURLException
 import java.net.URL
+import java.util.regex.PatternSyntaxException
 import scala.collection.{ mutable, immutable }
-import io.{ File, Directory, Path, Jar, AbstractFile }
+import scala.collection.convert.WrapAsScala.enumerationAsScalaIterator
 import scala.reflect.internal.util.StringOps.splitWhere
-import Jar.isJarOrZip
+import scala.tools.nsc.classpath.FileUtils
+
 import File.pathSeparator
-import scala.collection.convert.WrapAsScala.enumerationAsScalaIterator
-import java.net.MalformedURLException
-import java.util.regex.PatternSyntaxException
-import scala.reflect.runtime.ReflectionUtils
+import FileUtils.endsClass
+import FileUtils.endsScalaOrJava
+import Jar.isJarOrZip
 
 /** <p>
  *    This module provides star expansion of '-classpath' option arguments, behaves the same as
@@ -99,7 +102,7 @@ object ClassPath {
      */
     def validClassFile(name: String)  = endsClass(name) && isValidName(name)
     def validPackage(name: String)    = (name != "META-INF") && (name != "") && (name.charAt(0) != '.')
-    def validSourceFile(name: String) = endsScala(name) || endsJava(name)
+    def validSourceFile(name: String) = endsScalaOrJava(name)
 
     /** From the representation to its identifier.
      */
@@ -139,27 +142,19 @@ object ClassPath {
     def toBinaryName(rep: AbstractFile) = {
       val name = rep.name
       assert(endsClass(name), name)
-      name.substring(0, name.length - 6)
+      FileUtils.stripClassExtension(name)
     }
+
     def newClassPath(dir: AbstractFile) = new DirectoryClassPath(dir, this)
   }
 
   object DefaultJavaContext extends JavaContext
 
-  private def endsClass(s: String) = s.length > 6 && s.substring(s.length - 6) == ".class"
-  private def endsScala(s: String) = s.length > 6 && s.substring(s.length - 6) == ".scala"
-  private def endsJava(s: String)  = s.length > 5 && s.substring(s.length - 5) == ".java"
-
   /** From the source file to its identifier.
    */
-  def toSourceName(f: AbstractFile): String = {
-    val name = f.name
-
-    if (endsScala(name)) name.substring(0, name.length - 6)
-    else if (endsJava(name)) name.substring(0, name.length - 5)
-    else throw new FatalError("Unexpected source file ending: " + name)
-  }
+  def toSourceName(f: AbstractFile): String = FileUtils.stripSourceExtension(f.name)
 }
+
 import ClassPath._
 
 /**
@@ -177,10 +172,6 @@ abstract class ClassPath[T] extends ClassFileLookup[T] {
    */
   def origin: Option[String] = None
 
-  /** The whole classpath in the form of one String.
-   */
-  def asClasspathString: String
-
   /** Info which should be propagated to any sub-classpaths.
    */
   def context: ClassPathContext[T]
@@ -248,11 +239,9 @@ abstract class ClassPath[T] extends ClassFileLookup[T] {
       case _                                        => None
     }
 
-  override def asClassPathString: String = asClasspathString
-
   override def asSourcePathString: String = sourcepaths.mkString(pathSeparator)
 
-  def sortString = join(split(asClasspathString).sorted: _*)
+  def sortString = join(split(asClassPathString).sorted: _*)
   override def equals(that: Any) = that match {
     case x: ClassPath[_]  => this.sortString == x.sortString
     case _                => false
@@ -264,10 +253,12 @@ abstract class ClassPath[T] extends ClassFileLookup[T] {
  * A Classpath containing source files
  */
 class SourcePath[T](dir: AbstractFile, val context: ClassPathContext[T]) extends ClassPath[T] {
+  import FileUtils.AbstractFileOps
+
   def name = dir.name
   override def origin = dir.underlyingSource map (_.path)
-  def asURLs = if (dir.file == null) Nil else List(dir.toURL)
-  def asClasspathString = dir.path
+  def asURLs = dir.toURLs()
+  def asClassPathString = dir.path
   val sourcepaths: IndexedSeq[AbstractFile] = IndexedSeq(dir)
 
   private def traverse() = {
@@ -290,10 +281,12 @@ class SourcePath[T](dir: AbstractFile, val context: ClassPathContext[T]) extends
  * A directory (or a .jar file) containing classfiles and packages
  */
 class DirectoryClassPath(val dir: AbstractFile, val context: ClassPathContext[AbstractFile]) extends ClassPath[AbstractFile] {
+  import FileUtils.AbstractFileOps
+
   def name = dir.name
   override def origin = dir.underlyingSource map (_.path)
-  def asURLs = if (dir.file == null) List(new URL(name)) else List(dir.toURL)
-  def asClasspathString = dir.path
+  def asURLs = dir.toURLs(default = Seq(new URL(name)))
+  def asClassPathString = dir.path
   val sourcepaths: IndexedSeq[AbstractFile] = IndexedSeq()
 
   // calculates (packages, classes) in one traversal.
@@ -340,6 +333,7 @@ class MergedClassPath[T](
   override val entries: IndexedSeq[ClassPath[T]],
   val context: ClassPathContext[T])
 extends ClassPath[T] {
+
   def this(entries: TraversableOnce[ClassPath[T]], context: ClassPathContext[T]) =
     this(entries.toIndexedSeq, context)
 
@@ -348,7 +342,7 @@ extends ClassPath[T] {
   lazy val sourcepaths: IndexedSeq[AbstractFile] = entries flatMap (_.sourcepaths)
 
   override def origin = Some(entries map (x => x.origin getOrElse x.name) mkString ("Merged(", ", ", ")"))
-  override def asClasspathString: String = join(entries map (_.asClasspathString) : _*)
+  override def asClassPathString: String = join(entries map (_.asClassPathString) : _*)
 
   lazy val classes: IndexedSeq[ClassRepresentation[T]] = {
     var count   = 0
@@ -402,10 +396,12 @@ extends ClassPath[T] {
     }
     new MergedClassPath[T](newEntries, context)
   }
+
   def show() {
     println("ClassPath %s has %d entries and results in:\n".format(name, entries.size))
-    asClasspathString split ':' foreach (x => println("  " + x))
+    asClassPathString split ':' foreach (x => println("  " + x))
   }
+
   override def toString() = "merged classpath "+ entries.mkString("(", "\n", ")")
 }
 
diff --git a/src/repl/scala/tools/nsc/interpreter/ILoop.scala b/src/repl/scala/tools/nsc/interpreter/ILoop.scala
index 8bef424e2b..9f3f8375b1 100644
--- a/src/repl/scala/tools/nsc/interpreter/ILoop.scala
+++ b/src/repl/scala/tools/nsc/interpreter/ILoop.scala
@@ -622,8 +622,8 @@ class ILoop(in0: Option[BufferedReader], protected val out: JPrintWriter)
     if (f.exists) {
       addedClasspath = ClassPath.join(addedClasspath, f.path)
       intp.addUrlsToClassPath(f.toURI.toURL)
-      echo("Added '%s' to classpath.".format(f.path, intp.global.classPath.asClasspathString))
-      repldbg("Added '%s'.  Your new classpath is:\n\"%s\"".format(f.path, intp.global.classPath.asClasspathString))
+      echo("Added '%s' to classpath.".format(f.path, intp.global.classPath.asClassPathString))
+      repldbg("Added '%s'.  Your new classpath is:\n\"%s\"".format(f.path, intp.global.classPath.asClassPathString))
     }
     else echo("The path '" + f + "' doesn't seem to exist.")
   }
@@ -667,8 +667,8 @@ class ILoop(in0: Option[BufferedReader], protected val out: JPrintWriter)
     else {
       addedClasspath = ClassPath.join(addedClasspath, f.path)
       intp.addUrlsToClassPath(f.toURI.toURL)
-      echo("Added '%s' to classpath.".format(f.path, intp.global.classPath.asClasspathString))
-      repldbg("Added '%s'.  Your new classpath is:\n\"%s\"".format(f.path, intp.global.classPath.asClasspathString))
+      echo("Added '%s' to classpath.".format(f.path, intp.global.classPath.asClassPathString))
+      repldbg("Added '%s'.  Your new classpath is:\n\"%s\"".format(f.path, intp.global.classPath.asClassPathString))
     }
   }
 
diff --git a/src/scalap/scala/tools/scalap/Main.scala b/src/scalap/scala/tools/scalap/Main.scala
index 1faa855444..edad3bfc09 100644
--- a/src/scalap/scala/tools/scalap/Main.scala
+++ b/src/scalap/scala/tools/scalap/Main.scala
@@ -135,7 +135,7 @@ class Main {
      */
     def name              = ""
     def asURLs            = Nil
-    def asClasspathString = ""
+    def asClassPathString = ""
 
     val context     = DefaultJavaContext
     val classes     = IndexedSeq()