eol: don't fallback to use .hgeol from tip (BC)

eol: don't fallback to use .hgeol from tip (BC)

If no .hgeol were found in the current working directory, eol would fallback to
use the one in tip. That could in some cases give very confusing or wrong
behaviour when it applied wrong filters.

It might be convenient to have plain 'clone' immediately apply 'native'
encoding patterns in the cloned repo. But it is wrong to assume that this
revision is tip, and even more wrong to also apply it when not cloning - for
example when updating between history revisions. The encoding should always
match the content of the current .hgeol . It should never use anything else.

--- a/hgext/eol.py	Mon Oct 14 01:42:24 2019 +0200
+++ b/hgext/eol.py	Sun Oct 13 02:10:26 2019 +0200
@@ -387,7 +387,7 @@
             return eol.match
 
         def _hgcleardirstate(self):
-            self._eolmatch = self.loadeol([None, b'tip'])
+            self._eolmatch = self.loadeol([None])
             if not self._eolmatch:
                 self._eolmatch = util.never
                 return

--- a/tests/test-eol-clone.t	Mon Oct 14 01:42:24 2019 +0200
+++ b/tests/test-eol-clone.t	Sun Oct 13 02:10:26 2019 +0200
@@ -21,9 +21,8 @@
   adding .hgeol
   adding a.txt
 
-Test commit of removed .hgeol - currently it seems to live on as zombie
-(causing "filtering a.txt through tolf") after being removed ... but actually
-it is just confusing use of tip revision.
+Test commit of removed .hgeol and how it immediately makes the automatic
+changes explicit and committable.
 
   $ cd ..
   $ hg clone repo repo-2
@@ -41,7 +40,7 @@
   $ hg remove .hgeol
   $ touch a.txt *  # ensure consistent st dirtyness checks, ignoring dirstate timing
   $ hg st -v --debug
-  filtering a.txt through tolf
+  M a.txt
   R .hgeol
   $ hg commit -m 'remove eol'
   $ hg exp
@@ -49,16 +48,26 @@
   # User test
   # Date 0 0
   #      Thu Jan 01 00:00:00 1970 +0000
-  # Node ID c60b96c20c7de8c821127b548c34e5b170bcf9fe
+  # Node ID 3c20c2d90333b6ecdc8f7aa8f9b73223c7c7a608
   # Parent  90f94e2cf4e24628afddd641688dfe4cd476d6e4
   remove eol
   
-  diff -r 90f94e2cf4e2 -r c60b96c20c7d .hgeol
+  diff -r 90f94e2cf4e2 -r 3c20c2d90333 .hgeol
   --- a/.hgeol	Thu Jan 01 00:00:00 1970 +0000
   +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
   @@ -1,2 +0,0 @@
   -[patterns]
   -**.txt = native
+  diff -r 90f94e2cf4e2 -r 3c20c2d90333 a.txt
+  --- a/a.txt	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/a.txt	Thu Jan 01 00:00:00 1970 +0000
+  @@ -1,3 +1,3 @@
+  -first
+  -second
+  -third
+  +first\r (esc)
+  +second\r (esc)
+  +third\r (esc)
   $ hg push --quiet
   $ cd ..
 
@@ -75,7 +84,7 @@
   updating to branch default
   resolving manifests
    branchmerge: False, force: False, partial: False
-   ancestor: 000000000000, local: 000000000000+, remote: c60b96c20c7d
+   ancestor: 000000000000, local: 000000000000+, remote: 3c20c2d90333
   calling hook preupdate.eol: hgext.eol.preupdate
    a.txt: remote created -> g
   getting a.txt
@@ -83,9 +92,9 @@
   $ cd repo-3
 
   $ cat a.txt
-  first
-  second
-  third
+  first\r (esc)
+  second\r (esc)
+  third\r (esc)
 
 Test clone of revision with .hgeol