# HG changeset patch
# User Martin von Zweigbergk <martinvonz@google.com>
# Date 1555619660 25200
# Node ID 65fa61ca20af0d31eddb7d0a6353762f7e2d5220
# Parent  f3d06d37e194a9e85a4b24ccad4e77699a187f44
context: add ctx.files{modified,added,removed}() methods

Changeset-centric copy tracing is currently very slow because it often
reads manifests. One place it needs the manifest is in _chain(), where
it removes a copy X->Y if Y has subsequently gotten removed. I want to
speed that up by keeping track directly in the changeset of which
files are removed in the changeset. These methods will be similar to
ctx.p[12]copies() in that way: they will either read from the
changeset or calculate the information from the manifests otherwise.

Note that these are different from ctx.{modified,added,removed}() on
merge commits. Those functions always compare to p1, but the new ones
compare to both parents. filesadded() means "file does not exist in
either parent but exists now", filesremoved() means "file existed in
either parent but does not exist now", and filesmodified() means "file
existed in either parent and still exists". The set of files in
ctx.files() is the union of the files from the three new functions
(and the three new ones are all disjoint sets).

Also note that uncommitted merges are weird as usual. The invariant
mentioned above still holds, but the functions compare to p1 (and are
thus identical to the existing methods).

Differential Revision: https://phab.mercurial-scm.org/D6367

diff -r f3d06d37e194 -r 65fa61ca20af mercurial/context.py
--- a/mercurial/context.py	Thu May 09 15:09:07 2019 -0700
+++ b/mercurial/context.py	Thu Apr 18 13:34:20 2019 -0700
@@ -463,6 +463,24 @@
         return self._changeset.date
     def files(self):
         return self._changeset.files
+    def filesmodified(self):
+        modified = set(self.files())
+        modified.difference_update(self.filesadded())
+        modified.difference_update(self.filesremoved())
+        return sorted(modified)
+    def filesadded(self):
+        added = []
+        for f in self.files():
+            if not any(f in p for p in self.parents()):
+                added.append(f)
+        return added
+    def filesremoved(self):
+        removed = []
+        for f in self.files():
+            if f not in self:
+                removed.append(f)
+        return removed
+
     @propertycache
     def _copies(self):
         source = self._repo.ui.config('experimental', 'copies.read-from')
@@ -1170,6 +1188,10 @@
         return self._status.removed
     def deleted(self):
         return self._status.deleted
+    filesmodified = modified
+    filesadded = added
+    filesremoved = removed
+
     def branch(self):
         return encoding.tolocal(self._extra['branch'])
     def closesbranch(self):