sidedatacopies: directly fetch copies information from sidedata

sidedatacopies: directly fetch copies information from sidedata

When using the sidedata mode, we don't need a complicated and expensive
`context` object. Instead we directly fetch copies information from the
sidedata (through a changelogrevision object). More optimisations coming.

revision: large amount; added files: large amount; rename small amount; c3b14617fbd7 9ba6ab77fd29
filelog: ! wall 3.679613 comb 3.680000 user 3.580000 sys 0.100000 (median of 3)
base:    ! wall 8.884369 comb 8.880000 user 8.850000 sys 0.030000 (median of 3)
before:  ! wall 4.681985 comb 4.680000 user 4.640000 sys 0.040000 (median of 3)
after:   ! wall 3.955894 comb 3.950000 user 3.940000 sys 0.010000 (median of 3)
revision: large amount; added files: small amount; rename small amount; c3b14617fbd7 f650a9b140d2
filelog: ! wall 0.003357 comb 0.010000 user 0.010000 sys 0.000000 (median of 781)
base:    ! wall 12.398524 comb 12.400000 user 12.330000 sys 0.070000 (median of 3)
before:  ! wall 6.459592 comb 6.470000 user 6.390000 sys 0.080000 (median of 3)
after:   ! wall 5.505774 comb 5.500000 user 5.410000 sys 0.090000 (median of 3)
revision: large amount; added files: large amount; rename large amount; 08ea3258278e d9fa043f30c0
filelog: ! wall 2.754687 comb 2.760000 user 2.650000 sys 0.110000 (median of 4)
base:    ! wall 1.423166 comb 1.420000 user 1.400000 sys 0.020000 (median of 8)
before:  ! wall 0.961048 comb 0.960000 user 0.940000 sys 0.020000 (median of 11)
after:   ! wall 0.882950 comb 0.880000 user 0.880000 sys 0.000000 (median of 11)
revision: small amount; added files: large amount; rename large amount; df6f7a526b60 a83dc6a2d56f
filelog: ! wall 1.552293 comb 1.550000 user 1.510000 sys 0.040000 (median of 6
base:    ! wall 0.022662 comb 0.020000 user 0.020000 sys 0.000000 (median of 128)
before:  ! wall 0.021649 comb 0.020000 user 0.020000 sys 0.000000 (median of 135)
after:   ! wall 0.020951 comb 0.020000 user 0.020000 sys 0.000000 (median of 141)
revision: small amount; added files: large amount; rename small amount; 4aa4e1f8e19a 169138063d63
filelog: ! wall 1.500983 comb 1.500000 user 1.420000 sys 0.080000 (median of 7)
base:    ! wall 0.006956 comb 0.010000 user 0.010000 sys 0.000000 (median of 392)
before:  ! wall 0.004022 comb 0.000000 user 0.000000 sys 0.000000 (median of 735)
after:   ! wall 0.003988 comb 0.000000 user 0.000000 sys 0.000000 (median of 736)
revision: small amount; added files: small amount; rename small amount; 4bc173b045a6 964879152e2e
filelog: ! wall 0.011745 comb 0.020000 user 0.020000 sys 0.000000 (median of 250)
base:    ! wall 0.000156 comb 0.000000 user 0.000000 sys 0.000000 (median of 17180)
before:  ! wall 0.000118 comb 0.000000 user 0.000000 sys 0.000000 (median of 19170)
after:   ! wall 0.000097 comb 0.000000 user 0.000000 sys 0.000000 (median of 27276)
revision: medium amount; added files: large amount; rename medium amount; c95f1ced15f2 2c68e87c3efe
filelog: ! wall 3.228230 comb 3.230000 user 3.110000 sys 0.120000 (median of 4)
base:    ! wall 0.997640 comb 1.000000 user 0.980000 sys 0.020000 (median of 10)
before:  ! wall 0.679500 comb 0.680000 user 0.680000 sys 0.000000 (median of 15)
after:   ! wall 0.596779 comb 0.600000 user 0.600000 sys 0.000000 (median of 17)
revision: medium amount; added files: medium amount; rename small amount; d343da0c55a8 d7746d32bf9d
filelog: ! wall 1.052501 comb 1.060000 user 1.040000 sys 0.020000 (median of 10
base:    ! wall 0.214519 comb 0.220000 user 0.220000 sys 0.000000 (median of 45)
before:  ! wall 0.149675 comb 0.150000 user 0.150000 sys 0.000000 (median of 66)
after:   ! wall 0.130786 comb 0.130000 user 0.130000 sys 0.000000 (median of 75)

Differential Revision: https://phab.mercurial-scm.org/D7072

--- a/mercurial/copies.py	Tue Oct 15 18:42:03 2019 +0200
+++ b/mercurial/copies.py	Wed Oct 02 17:53:47 2019 -0400
@@ -190,12 +190,25 @@
     cl = repo.changelog
     parents = cl.parentrevs
 
-    def revinfo(rev):
-        p1, p2 = parents(rev)
-        ctx = repo[rev]
-        p1copies, p2copies = ctx._copies
-        removed = ctx.filesremoved()
-        return p1, p2, p1copies, p2copies, removed
+    if repo.filecopiesmode == b'changeset-sidedata':
+        changelogrevision = cl.changelogrevision
+
+        def revinfo(rev):
+            p1, p2 = parents(rev)
+            c = changelogrevision(rev)
+            p1copies = c.p1copies
+            p2copies = c.p2copies
+            removed = c.filesremoved
+            return p1, p2, p1copies, p2copies, removed
+
+    else:
+
+        def revinfo(rev):
+            p1, p2 = parents(rev)
+            ctx = repo[rev]
+            p1copies, p2copies = ctx._copies
+            removed = ctx.filesremoved()
+            return p1, p2, p1copies, p2copies, removed
 
     return revinfo