[Truffle] Add File.flock

spec/truffle/tags/core/file/flock_tags.txt

@@ -1,6 +1,3 @@
-fails:File#flock exclusively locks a file
-fails:File#flock non-exclusively locks a file
-fails:File#flock returns false if trying to lock an exclusively locked file
 fails:File#flock blocks if trying to lock an exclusively locked file
 fails:File#flock returns 0 if trying to lock a non-exclusively locked file
 fails:File#flock fails with EBADF acquiring exclusive lock on read-only File

spec/truffle/tags/core/file/grpowned_tags.txt

@@ -1,4 +1,2 @@
 fails:File.grpowned? takes non primary groups into account
 fails(windows):File.grpowned? returns false if the file exist
-fails:File.grpowned? returns true if the file exist
-fails:File.grpowned? accepts an object that has a #to_path method

spec/truffle/tags/core/file/open_tags.txt

@@ -6,8 +6,5 @@ fails:File.open raises a SystemCallError if passed an invalid Integer type
 fails:File.open with a block does not raise error when file is closed inside the block
 fails:File.open with a block does not propagate StandardErrors produced by close
 fails:File.open on a FIFO opens it as a normal file
-fails:File.open when passed a file descriptor opens a file
-fails:File.open when passed a file descriptor opens a file when passed a block
-fails:File.open opens directories
 fails:File.open opens a file with a file descriptor d and a block
 fails:File.open with a block propagates StandardErrors produced by close

spec/truffle/tags/core/file/realdirpath_tags.txt

@@ -1,10 +1,7 @@
-fails:File.realdirpath returns '/' when passed '/'
 fails:File.realdirpath returns the real (absolute) pathname not containing symlinks
 fails:File.realdirpath uses base directory for interpreting relative pathname
 fails:File.realdirpath uses current directory for interpreting relative pathname
 fails:File.realdirpath uses link directory for expanding relative links
 fails:File.realdirpath raises an Errno::ELOOP if the symlink points to itself
-fails:File.realdirpath returns the real (absolute) pathname if the file is absent
-fails:File.realdirpath raises Errno::ENOENT if the directory is absent
 fails:File.realdirpath returns the real (absolute) pathname if the symlink points to an absent file
 fails:File.realdirpath raises Errno::ENOENT if the symlink points to an absent directory

spec/truffle/tags/core/filetest/grpowned_tags.txt

@@ -1,3 +1 @@
 fails:FileTest.grpowned? takes non primary groups into account
-fails:FileTest.grpowned? returns true if the file exist
-fails:FileTest.grpowned? accepts an object that has a #to_path method

truffle/src/main/java/org/jruby/truffle/nodes/rubinius/PosixNodes.java

@@ -266,6 +266,20 @@ public int chdir(RubyString path) {
 
     }
 
+    @CoreMethod(names = "flock", isModuleFunction = true, required = 2, lowerFixnumParameters = {0, 1})
+    public abstract static class FlockNode extends PointerPrimitiveNodes.ReadAddressPrimitiveNode {
+
+        public FlockNode(RubyContext context, SourceSection sourceSection) {
+            super(context, sourceSection);
+        }
+
+        @Specialization
+        public int flock(int fd, int constant) {
+            return posix().flock(fd, constant);
+        }
+
+    }
+
     @CoreMethod(names = "rmdir", isModuleFunction = true, required = 1)
     public abstract static class RmdirNode extends PointerPrimitiveNodes.ReadAddressPrimitiveNode {