[PATCH 1 of 2 issue3059 v2] util: add progress callback support to copyfiles

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <augie at google.com>
# Date 1426775062 14400
#      Thu Mar 19 10:24:22 2015 -0400
# Node ID 56319892a54a2694762861f22be751fd28a25813
# Parent  5cb459dc32d209653a3e5d77749cf989ab9a51e4
util: add progress callback support to copyfiles

diff --git a/mercurial/hg.py b/mercurial/hg.py
--- a/mercurial/hg.py
+++ b/mercurial/hg.py
@@ -258,8 +258,8 @@ def copystore(ui, srcrepo, destpath):
                     lockfile = os.path.join(dstbase, "lock")
                     # lock to avoid premature writing to the target
                     destlock = lock.lock(dstvfs, lockfile)
-                hardlink, n = util.copyfiles(srcvfs.join(f), dstvfs.join(f),
-                                             hardlink)
+                hardlink, n, topic = util.copyfiles(
+                    srcvfs.join(f), dstvfs.join(f), hardlink)
                 num += n
         if hardlink:
             ui.debug("linked %d files\n" % num)
diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -739,20 +739,36 @@ def copyfile(src, dest, hardlink=False):
         except shutil.Error, inst:
             raise Abort(str(inst))
 
-def copyfiles(src, dst, hardlink=None):
-    """Copy a directory tree using hardlinks if possible"""
+def copyfiles(src, dst, hardlink=None,
+              progress=lambda t, pos: None, poffset=None):
+    """Copy a directory tree using hardlinks if possible.
+
+    If progress could be split across multiple copyfiles calls,
+    poffset. Otherwise, copyfiles() will close its progress topic.
+    """
+    if poffset is None:
+        closeprog = True
+        poffset = 0
+    else:
+        closeprog = False
+    num = 0
 
     if hardlink is None:
         hardlink = (os.stat(src).st_dev ==
                     os.stat(os.path.dirname(dst)).st_dev)
+    if hardlink:
+        topic = _('linking')
+    else:
+        topic = _('copying')
 
-    num = 0
     if os.path.isdir(src):
         os.mkdir(dst)
         for name, kind in osutil.listdir(src):
             srcname = os.path.join(src, name)
             dstname = os.path.join(dst, name)
-            hardlink, n = copyfiles(srcname, dstname, hardlink)
+            hardlink, n, junk_topic = copyfiles(srcname, dstname, hardlink,
+                                                progress=progress,
+                                                poffset=poffset + num)
             num += n
     else:
         if hardlink:
@@ -764,8 +780,12 @@ def copyfiles(src, dst, hardlink=None):
         else:
             shutil.copy(src, dst)
         num += 1
+        progress(topic, poffset + num)
 
-    return hardlink, num
+    if closeprog:
+        progress(topic, None)
+
+    return hardlink, num, topic
 
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