mergeresult: introduce dedicated tuple for no-op actions

mergeresult: introduce dedicated tuple for no-op actions

This will help us in adding more no-op actions in next patch while keeping the
code cleaner.

--- a/mercurial/merge.py	Fri Jun 19 13:27:46 2020 +0200
+++ b/mercurial/merge.py	Mon Sep 14 13:51:39 2020 +0530
@@ -523,7 +523,6 @@
     narrowed.
     """
     # TODO: handle with nonconflicttypes
-    nooptypes = {mergestatemod.ACTION_KEEP}
     nonconflicttypes = {
         mergestatemod.ACTION_ADD,
         mergestatemod.ACTION_ADD_MODIFIED,
@@ -541,7 +540,7 @@
             pass
         elif not branchmerge:
             mresult.removefile(f)  # just updating, ignore changes outside clone
-        elif action[0] in nooptypes:
+        elif action[0] in mergeresult.NO_OP_ACTIONS:
             mresult.removefile(f)  # merge does not affect file
         elif action[0] in nonconflicttypes:
             raise error.Abort(
@@ -564,6 +563,8 @@
     It has information about what actions need to be performed on dirstate
     mapping of divergent renames and other such cases. '''
 
+    NO_OP_ACTIONS = (mergestatemod.ACTION_KEEP,)
+
     def __init__(self):
         """
         filemapping: dict of filename as keys and action related info as values
@@ -711,12 +712,12 @@
                 a
                 not in (
                     mergestatemod.ACTION_GET,
-                    mergestatemod.ACTION_KEEP,
                     mergestatemod.ACTION_EXEC,
                     mergestatemod.ACTION_REMOVE,
                     mergestatemod.ACTION_PATH_CONFLICT_RESOLVE,
                 )
                 and self._actionmapping[a]
+                and a not in self.NO_OP_ACTIONS
             ):
                 return True
 
@@ -1420,7 +1421,7 @@
             wctx[f].audit()
             wctx[f].remove()
 
-    numupdates = mresult.len() - mresult.len((mergestatemod.ACTION_KEEP,))
+    numupdates = mresult.len() - mresult.len(mergeresult.NO_OP_ACTIONS)
     progress = repo.ui.makeprogress(
         _(b'updating'), unit=_(b'files'), total=numupdates
     )

--- a/mercurial/sparse.py	Fri Jun 19 13:27:46 2020 +0200
+++ b/mercurial/sparse.py	Mon Sep 14 13:51:39 2020 +0530
@@ -399,7 +399,7 @@
             temporaryfiles.append(file)
             prunedactions[file] = action
         elif branchmerge:
-            if type != mergestatemod.ACTION_KEEP:
+            if type not in mergemod.mergeresult.NO_OP_ACTIONS:
                 temporaryfiles.append(file)
                 prunedactions[file] = action
         elif type == mergestatemod.ACTION_FORGET: