( )⚙ D6344 copies: remove redundant filtering of ping-pong renames in _chain()

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Differential D6344

copies: remove redundant filtering of ping-pong renames in _chain()
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Authored by martinvonz on May 5 2019, 1:30 AM.

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rHG00e065fb1469: copies: remove redundant filtering of ping-pong renames in _chain()
Summary

We already handle the ping-pong rename case in the filtering step, so
there's very little point in doing it in the chaining loop (ping-pong
renames are very rare, so I'm not worried about the cost of adding it
and then removing it again).

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Event Timeline

martinvonz created this revision.May 5 2019, 1:30 AM
Closed by commit rHG00e065fb1469: copies: remove redundant filtering of ping-pong renames in _chain() (authored by martinvonz). · Explain WhyMay 6 2019, 12:00 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/copies.py (6 lines)

Diff 15019

mercurial/copies.py

# 6 x x y x->y # 6 x x y x->y
# Initialize result ('t') from 'a'. This catches cases 1 & 2. We'll remove # Initialize result ('t') from 'a'. This catches cases 1 & 2. We'll remove
# case 1 later. We'll also catch cases 3 & 4 here. Case 4 will be # case 1 later. We'll also catch cases 3 & 4 here. Case 4 will be
# overwritten later, and case 3 will be removed later. # overwritten later, and case 3 will be removed later.
t = a.copy() t = a.copy()
for k, v in b.iteritems(): for k, v in b.iteritems():
if v in t: if v in t:
# found a chain, i.e. cases 3 & 4. # Found a chain, i.e. cases 3 & 4. We'll remove case 3 later.
if t[v] != k:
# file wasn't renamed back to itself (i.e. case 4, not 3)
t[k] = t[v] t[k] = t[v]
else: else:
# Renamed only in 'b', i.e. cases 5 & 6. We'll remove case 5 later. # Renamed only in 'b', i.e. cases 5 & 6. We'll remove case 5 later.
t[k] = v t[k] = v
for k, v in list(t.items()): for k, v in list(t.items()):
# remove copies from files that didn't exist, i.e. case 5 # remove copies from files that didn't exist, i.e. case 5
if v not in src: if v not in src:
del t[k] del t[k]