# HG changeset patch
# User Martin von Zweigbergk <martinvonz@google.com>
# Date 2019-01-18 21:13:30
# Node ID 456ad0fd8e188373f9fb4e42b80caaa36a3db932
# Parent  58d50c697dc723b1ed62fe78df8b67cb1f020b09

context: introduce p[12]copies() methods and debugp[12]copies commands

As mentioned earlier, I'm working on support for storing copy metadata
in the changeset instead of in the filelog.

In order to transition a repo from storing metadata in filelogs to
storing it in the changeset, I'm going to provide a config option for
reading the metadata from the changeset, but falling back to getting
it from the filelog if it's not in the changeset. In this compatiblity
mode, the changeset-optmized algorithms will be used. We will then
need to convert the filelog copy metadata to look like that provided
by changeset copy metadata. This patch introduces methods that do just
that.

By having these methods here, we can start writing changeset-optimized
algorithms that should work already before we add any support for
storing the metadata in the changesets.

This commit also includes new debugp[12]copies commands and exercises
them in test-copies.t.

Differential Revision: https://phab.mercurial-scm.org/D5990

diff --git a/mercurial/context.py b/mercurial/context.py
--- a/mercurial/context.py
+++ b/mercurial/context.py
@@ -439,6 +439,29 @@ class changectx(basectx):
         return self._changeset.date
     def files(self):
         return self._changeset.files
+    @propertycache
+    def _copies(self):
+        p1copies = {}
+        p2copies = {}
+        p1 = self.p1()
+        p2 = self.p2()
+        narrowmatch = self._repo.narrowmatch()
+        for dst in self.files():
+            if not narrowmatch(dst) or dst not in self:
+                continue
+            copied = self[dst].renamed()
+            if not copied:
+                continue
+            src, srcnode = copied
+            if src in p1 and p1[src].filenode() == srcnode:
+                p1copies[dst] = src
+            elif src in p2 and p2[src].filenode() == srcnode:
+                p2copies[dst] = src
+        return p1copies, p2copies
+    def p1copies(self):
+        return self._copies[0]
+    def p2copies(self):
+        return self._copies[1]
     def description(self):
         return self._changeset.description
     def branch(self):
@@ -1158,7 +1181,26 @@ class committablectx(basectx):
     def files(self):
         return sorted(self._status.modified + self._status.added +
                       self._status.removed)
-
+    @propertycache
+    def _copies(self):
+        p1copies = {}
+        p2copies = {}
+        parents = self._repo.dirstate.parents()
+        p1manifest = self._repo[parents[0]].manifest()
+        p2manifest = self._repo[parents[1]].manifest()
+        narrowmatch = self._repo.narrowmatch()
+        for dst, src in self._repo.dirstate.copies().items():
+            if not narrowmatch(dst):
+                continue
+            if src in p1manifest:
+                p1copies[dst] = src
+            elif src in p2manifest:
+                p2copies[dst] = src
+        return p1copies, p2copies
+    def p1copies(self):
+        return self._copies[0]
+    def p2copies(self):
+        return self._copies[1]
     def modified(self):
         return self._status.modified
     def added(self):
@@ -1810,6 +1852,30 @@ class overlayworkingctx(committablectx):
         return [f for f in self._cache.keys() if
                 not self._cache[f]['exists'] and self._existsinparent(f)]
 
+    def p1copies(self):
+        copies = self._repo._wrappedctx.p1copies().copy()
+        narrowmatch = self._repo.narrowmatch()
+        for f in self._cache.keys():
+            if not narrowmatch(f):
+                continue
+            copies.pop(f, None) # delete if it exists
+            source = self._cache[f]['copied']
+            if source:
+                copies[f] = source
+        return copies
+
+    def p2copies(self):
+        copies = self._repo._wrappedctx.p2copies().copy()
+        narrowmatch = self._repo.narrowmatch()
+        for f in self._cache.keys():
+            if not narrowmatch(f):
+                continue
+            copies.pop(f, None) # delete if it exists
+            source = self._cache[f]['copied']
+            if source:
+                copies[f] = source
+        return copies
+
     def isinmemory(self):
         return True
 
diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -1741,6 +1741,28 @@ def debugobsolete(ui, repo, precursor=No
             cmdutil.showmarker(fm, m, index=ind)
         fm.end()
 
+@command('debugp1copies',
+         [('r', 'rev', '', _('revision to debug'), _('REV'))],
+         _('[-r REV]'))
+def debugp1copies(ui, repo, **opts):
+    """dump copy information compared to p1"""
+
+    opts = pycompat.byteskwargs(opts)
+    ctx = scmutil.revsingle(repo, opts.get('rev'), default=None)
+    for dst, src in ctx.p1copies().items():
+        ui.write('%s -> %s\n' % (src, dst))
+
+@command('debugp2copies',
+         [('r', 'rev', '', _('revision to debug'), _('REV'))],
+         _('[-r REV]'))
+def debugp1copies(ui, repo, **opts):
+    """dump copy information compared to p2"""
+
+    opts = pycompat.byteskwargs(opts)
+    ctx = scmutil.revsingle(repo, opts.get('rev'), default=None)
+    for dst, src in ctx.p2copies().items():
+        ui.write('%s -> %s\n' % (src, dst))
+
 @command('debugpathcomplete',
          [('f', 'full', None, _('complete an entire path')),
           ('n', 'normal', None, _('show only normal files')),
diff --git a/tests/test-completion.t b/tests/test-completion.t
--- a/tests/test-completion.t
+++ b/tests/test-completion.t
@@ -103,6 +103,8 @@ Show debug commands if there are no othe
   debugmergestate
   debugnamecomplete
   debugobsolete
+  debugp1copies
+  debugp2copies
   debugpathcomplete
   debugpathcopies
   debugpeer
@@ -280,6 +282,8 @@ Show all commands + options
   debugmergestate: 
   debugnamecomplete: 
   debugobsolete: flags, record-parents, rev, exclusive, index, delete, date, user, template
+  debugp1copies: rev
+  debugp2copies: rev
   debugpathcomplete: full, normal, added, removed
   debugpathcopies: include, exclude
   debugpeer: 
diff --git a/tests/test-copies.t b/tests/test-copies.t
--- a/tests/test-copies.t
+++ b/tests/test-copies.t
@@ -17,12 +17,17 @@ Simple rename case
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
+  $ hg debugp1copies
+  x -> y
+  $ hg debugp2copies
   $ hg ci -m 'rename x to y'
   $ hg l
   @  1 rename x to y
   |  x y
   o  0 add x
      x
+  $ hg debugp1copies -r 1
+  x -> y
   $ hg debugpathcopies 0 1
   x -> y
   $ hg debugpathcopies 1 0
@@ -41,12 +46,17 @@ Copy a file onto another file
   $ echo y > y
   $ hg ci -Aqm 'add x and y'
   $ hg cp -f x y
+  $ hg debugp1copies
+  x -> y
+  $ hg debugp2copies
   $ hg ci -m 'copy x onto y'
   $ hg l
   @  1 copy x onto y
   |  y
   o  0 add x and y
      x y
+  $ hg debugp1copies -r 1
+  x -> y
 Incorrectly doesn't show the rename
   $ hg debugpathcopies 0 1
 
@@ -63,6 +73,8 @@ produce a new filelog entry. The changes
   |  x2
   o  0 add x and x2 with same content
      x x2
+  $ hg debugp1copies -r 1
+  x -> x2
 Incorrectly doesn't show the rename
   $ hg debugpathcopies 0 1
 
@@ -85,6 +97,8 @@ Copy a file, then delete destination, th
   |  y
   o  0 add x
      x
+  $ hg debugp1copies -r 3
+  x -> y
   $ hg debugpathcopies 0 3
   x -> y
 
@@ -93,6 +107,9 @@ Rename file in a loop: x->y->z->x
   $ echo x > x
   $ hg ci -Aqm 'add x'
   $ hg mv x y
+  $ hg debugp1copies
+  x -> y
+  $ hg debugp2copies
   $ hg ci -m 'rename x to y'
   $ hg mv y z
   $ hg ci -m 'rename y to z'
@@ -129,6 +146,7 @@ end up reporting y as copied from x (if 
   |  x y
   o  0 add x
      x
+  $ hg debugp1copies -r 3
   $ hg debugpathcopies 0 3
 
 Copy x to z, then remove z, then copy x2 (same content as x) to z. With copy metadata in the
@@ -153,6 +171,8 @@ to the first commit that added the file.
   |  z
   o  0 add x and x2 with same content
      x x2
+  $ hg debugp1copies -r 3
+  x2 -> z
   $ hg debugpathcopies 0 3
   x2 -> z
 
@@ -225,6 +245,8 @@ Merge rename from other branch
   $ echo z > z
   $ hg ci -Aqm 'add z'
   $ hg merge -q 1
+  $ hg debugp1copies
+  $ hg debugp2copies
   $ hg ci -m 'merge rename from p2'
   $ hg l
   @    3 merge rename from p2
@@ -237,6 +259,8 @@ Merge rename from other branch
      x
 Perhaps we should indicate the rename here, but `hg status` is documented to be weird during
 merges, so...
+  $ hg debugp1copies -r 3
+  $ hg debugp2copies -r 3
   $ hg debugpathcopies 0 3
   x -> y
   $ hg debugpathcopies 1 2
@@ -254,10 +278,16 @@ Copy file from either side in a merge
   $ hg ci -Aqm 'add y'
   $ hg merge -q 0
   $ hg cp y z
+  $ hg debugp1copies
+  y -> z
+  $ hg debugp2copies
   $ hg ci -m 'copy file from p1 in merge'
   $ hg co -q 1
   $ hg merge -q 0
   $ hg cp x z
+  $ hg debugp1copies
+  $ hg debugp2copies
+  x -> z
   $ hg ci -qm 'copy file from p2 in merge'
   $ hg l
   @    3 copy file from p2 in merge
@@ -268,9 +298,15 @@ Copy file from either side in a merge
   |    y
   o  0 add x
      x
+  $ hg debugp1copies -r 2
+  y -> z
+  $ hg debugp2copies -r 2
   $ hg debugpathcopies 1 2
   y -> z
   $ hg debugpathcopies 0 2
+  $ hg debugp1copies -r 3
+  $ hg debugp2copies -r 3
+  x -> z
   $ hg debugpathcopies 1 3
   $ hg debugpathcopies 0 3
   x -> z
@@ -284,6 +320,9 @@ Copy file that exists on both sides of t
   $ hg ci -Aqm 'add x on branch 2'
   $ hg merge -q 0
   $ hg cp x z
+  $ hg debugp1copies
+  x -> z
+  $ hg debugp2copies
   $ hg ci -qm 'merge'
   $ hg l
   @    2 merge
@@ -292,6 +331,9 @@ Copy file that exists on both sides of t
   |    x
   o  0 add x on branch 1
      x
+  $ hg debugp1copies -r 2
+  x -> z
+  $ hg debugp2copies -r 2
 It's a little weird that it shows up on both sides
   $ hg debugpathcopies 1 2
   x -> z
@@ -312,6 +354,9 @@ Copy file that exists on both sides of t
   $ hg resolve -m x
   (no more unresolved files)
   $ hg cp x z
+  $ hg debugp1copies
+  x -> z
+  $ hg debugp2copies
   $ hg ci -qm 'merge'
   $ hg l
   @    2 merge
@@ -320,6 +365,9 @@ Copy file that exists on both sides of t
   |    x
   o  0 add x on branch 1
      x
+  $ hg debugp1copies -r 2
+  $ hg debugp2copies -r 2
+  x -> z
   $ hg debugpathcopies 1 2
   $ hg debugpathcopies 0 2
   x -> z
@@ -345,6 +393,8 @@ of the merge to the merge should include
   |/   y
   o  0 add x
      x
+  $ hg debugp1copies -r 3
+  $ hg debugp2copies -r 3
   $ hg debugpathcopies 2 3
   x -> y
   $ hg debugpathcopies 1 3
@@ -375,6 +425,9 @@ first side should not include the y->z r
   |/   y
   o  0 add x
      x
+  $ hg debugp1copies -r 3
+  y -> z
+  $ hg debugp2copies -r 3
   $ hg debugpathcopies 2 3
   y -> z
   $ hg debugpathcopies 1 3
diff --git a/tests/test-help.t b/tests/test-help.t
--- a/tests/test-help.t
+++ b/tests/test-help.t
@@ -1011,6 +1011,10 @@ Test list of internal help commands
    debugoptADV   (no help text available)
    debugoptDEP   (no help text available)
    debugoptEXP   (no help text available)
+   debugp1copies
+                 dump copy information compared to p1
+   debugp2copies
+                 dump copy information compared to p2
    debugpathcomplete
                  complete part or all of a tracked path
    debugpathcopies