--- a/hgext/evolve.py	Mon Jun 30 10:25:08 2014 -0400
+++ b/hgext/evolve.py	Mon Jun 30 13:29:49 2014 -0400
@@ -2074,32 +2074,61 @@
         lockmod.release(lock, wlock)
 
 @command('^fold|squash',
-    [('r', 'rev', [], _("explicitly specify the full set of revision to fold")),
+    [('r', 'rev', [], _("revision to fold")),
+     ('', 'exact', None, _("only fold specified revisions"))
     ] + commitopts + commitopts2,
-    # allow to choose the seed ?
-    _('rev'))
+    _('hg fold [OPTION]... [-r] REV'))
 def fold(ui, repo, *revs, **opts):
-    """Fold multiple revisions into a single one
+    """fold multiple revisions into a single one
+
+    Folds a set of revisions with the parent of the working directory.
+    All revisions linearly between the given revisions and the parent
+    of the working directory will also be folded.
+
+    Use --exact for folding only the specified revisions while ignoring the
+    parent of the working directory. In this case, the given revisions must
+    form a linear unbroken chain.
+
+    .. container:: verbose
+
+     Some examples:
+
+     - Fold the current revision with its parent::
 
-    The revisions from your current working directory to the given one are folded
-    into a single successor revision.
+         hg fold .^
+
+     - Fold all draft revisions with working directory parent::
+
+         hg fold 'draft()'
 
-    you can alternatively use --rev to explicitly specify revisions to be folded,
-    ignoring the current working directory parent.
+       See :hg:`help phases` for more about draft revisions and
+       :hg:`help revsets` for more about the `draft()` keyword
+
+     - Fold revisions 3, 4, 5, and 6 with the working directory parent::
+
+         hg fold 3:6
+
+     - Only fold revisions linearly between foo and @::
+
+         hg fold foo::@ --exact
     """
     revs = list(revs)
-    if revs:
-        if opts.get('rev', ()):
-            raise util.Abort("cannot specify both --rev and a target revision")
-        targets = scmutil.revrange(repo, revs)
-        revs = repo.revs('(%ld::.) or (.::%ld)', targets, targets)
-    elif 'rev' in opts:
-        revs = scmutil.revrange(repo, opts['rev'])
-    else:
-        revs = ()
+    revs.extend(opts['rev'])
     if not revs:
         raise util.Abort(_('no revisions specified'))
 
+    revs = scmutil.revrange(repo, revs)
+
+    if not opts['exact']:
+        # Try to extend given revision starting from the working directory
+        extrevs = repo.revs('(%ld::.) or (.::%ld)', revs, revs)
+        discardedrevs = [r for r in revs if r not in extrevs]
+        if discardedrevs:
+            raise util.Abort(_("cannot fold non-linear revisions"),
+                               hint=_("given revisions are unrelated to parent "
+                                      "of working directory"))
+        revs = extrevs
+
     if len(revs) == 1:
         ui.write_err(_('single revision specified, nothing to fold\n'))
         return 1

--- a/tests/test-evolve.t	Mon Jun 30 10:25:08 2014 -0400
+++ b/tests/test-evolve.t	Mon Jun 30 13:29:49 2014 -0400
@@ -616,27 +616,23 @@
   $ hg fold
   abort: no revisions specified
   [255]
-  $ hg fold 6 --rev 10
-  abort: cannot specify both --rev and a target revision
-  [255]
   $ hg fold .
   single revision specified, nothing to fold
   [1]
-  $ hg fold 6 # want to run hg fold 6
-  2 changesets folded
+  $ hg fold 10 1
+  abort: cannot fold non-linear revisions
+  (given revisions are unrelated to parent of working directory)
+  [255]
+  $ hg fold -r 5
+  3 changesets folded
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
-  $ glog
-  @  11:dd4682c1a481@default(draft) add 1
-  |
-  o  5:0b9e50c35132@default(draft) add 3
-  |
-  o  4:ce341209337f@default(draft) add 4
-  |
-  | o  1:73d38bb17fd7@default(draft) add 1
-  |/
-  o  0:8685c6d34325@default(draft) add 0
+  $ hg fold 6 # want to run hg fold 6
+  abort: unknown revision '6'!
+  [255]
+  $ hg log -r 11 --template '{desc}\n'
+  add 3
   
-  $ hg log -r 11 --template '{desc}\n'
+  
   add 1
   
   
@@ -648,8 +644,8 @@
 
   $ hg up 4
   0 files updated, 0 files merged, 2 files removed, 0 files unresolved
-  $ hg fold --rev 4::11 --user victor
-  3 changesets folded
+  $ hg fold --rev 4::11 --user victor --exact
+  2 changesets folded
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ glog
   @  12:d26d339c513f@default(draft) add 4
@@ -680,8 +676,7 @@
 
   $ hg olog
   4	: add 4 - test
-  5	: add 3 - test
-  11	: add 1 - test
+  11	: add 3 - test
 
 Test obsstore stat
 

--- a/tests/test-tutorial.t	Mon Jun 30 10:25:08 2014 -0400
+++ b/tests/test-tutorial.t	Mon Jun 30 13:29:49 2014 -0400
@@ -473,21 +473,24 @@
 The tutorial part is not written yet but can use `hg fold`:
 
   $ hg help fold
-  hg fold rev
+  hg fold [OPTION]... [-r] REV
   
   aliases: squash
   
-  Fold multiple revisions into a single one
+  fold multiple revisions into a single one
   
-      The revisions from your current working directory to the given one are
-      folded into a single successor revision.
+      Folds a set of revisions with the parent of the working directory. All
+      revisions linearly between the given revisions and the parent of the
+      working directory will also be folded.
   
-      you can alternatively use --rev to explicitly specify revisions to be
-      folded, ignoring the current working directory parent.
+      Use --exact for folding only the specified revisions while ignoring the
+      parent of the working directory. In this case, the given revisions must
+      form a linear unbroken chain.
   
   options:
   
-   -r --rev VALUE [+] explicitly specify the full set of revision to fold
+   -r --rev VALUE [+] revision to fold
+      --exact         only fold specified revisions
    -m --message TEXT  use text as commit message
    -l --logfile FILE  read commit message from file
    -d --date DATE     record the specified date as commit date
@@ -495,7 +498,7 @@
   
   [+] marked option can be specified multiple times
   
-  use "hg -v help fold" to show the global options
+  use "hg -v help fold" to show more complete help and the global options
 
 
 -----------------------