resolve: split test

Part of test-resolve.t is split into multiple tests to create an
injection point for new tests that will be added in subsequent patches.

tests/test-resolve.t

@@ -1,46 +1,53 b''
 test that a commit clears the merge state.
 
   $ hg init repo
   $ cd repo
 
   $ echo foo > file
   $ hg commit -Am 'add file'
   adding file
 
   $ echo bar >> file
   $ hg commit -Am 'append bar'
 
 
 create a second head
 
   $ hg up -C 0
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo baz >> file
   $ hg commit -Am 'append baz'
   created new head
 
 failing merge
 
   $ hg merge --tool=internal:fail
   0 files updated, 0 files merged, 0 files removed, 1 files unresolved
   use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
   [1]
 
+resolve -l should contain an unresolved entry
+
+  $ hg resolve -l
+  U file
+
+resolve the failure
+
   $ echo resolved > file
   $ hg resolve -m file
   $ hg commit -m 'resolved'
 
 resolve -l, should be empty
 
   $ hg resolve -l
 
 test crashed merge with empty mergestate
 
   $ mkdir .hg/merge
   $ touch .hg/merge/state
 
 resolve -l, should be empty
 
   $ hg resolve -l
 
   $ cd ..