[RFC PATCH 0/5] line-log: towards a more responsive, incremental 'git log -L'

Line-level log performs a preprocessing step in prepare_revision_walk(), during which it filters and rewrites history to keep only commits modifying the given line range. This preprocessing causes significant delay before the first commit is shown, wastes CPU time when the user asks only for a few commits, and does parent rewriting with no way to turn it off.

This patch series addresses these issues by integrating line-level log filtering into the revision walking machinery and making it work together with generation number-based topo-ordering (though for now only in the case when the user doesn't explicitly asks for parent rewriting, which is probably the common case).

The first two patches are quite straightforward (and arguably somewhat unrelated), but the rest deals with history traversal and parent rewriting, which I don't usually do, hence the RFC.

SZEDER Gábor (5):
  completion: offer '--(no-)patch' among 'git log' options
  line-log: remove unused fields from 'struct line_log_data'
  t4211-line-log: add tests for parent oids
  line-log: more responsive, incremental 'git log -L'
  line-log: try to use generation number-based topo-ordering

 contrib/completion/git-completion.bash |  1 +
 line-log.c                             |  4 +-
 line-log.h                             |  5 +-
 revision.c                             | 38 +++++++++++---
 t/t4211-line-log.sh                    | 68 ++++++++++++++++++++++++++
 5 files changed, 105 insertions(+), 11 deletions(-)