Merge branch 'kk/merge-base-exhaustion' into seen
The merge-base computation has been optimized by stopping the walk early when one side's exclusive commits in the queue are exhausted, yielding significant speedups for queries with one-sided histories. * kk/merge-base-exhaustion: commit-reach: remove commit-date ordering fallback commit-reach: move min_generation check into paint_queue_get() commit-reach: terminate merge-base walk when one paint side is exhausted commit-reach: introduce struct paint_state with per-side counters t6600: add clock-skew topologies and step counts for edge cases commit-reach: add trace2 instrumentation to paint_down_to_common() t6099, t6600: add side-exhaustion regression tests t6600: add test cases for side-exhaustion edge cases test-lib-functions: improve diagnostic output for trace2 data assertions Documentation/technical: add paint-down-to-common docseen
Junio C Hamano
commit
46a667095f
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@ -129,6 +129,7 @@ TECH_DOCS += technical/long-running-process-protocol
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TECH_DOCS += technical/multi-pack-index
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TECH_DOCS += technical/packfile-uri
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TECH_DOCS += technical/pack-heuristics
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TECH_DOCS += technical/paint-down-to-common
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TECH_DOCS += technical/parallel-checkout
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TECH_DOCS += technical/partial-clone
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TECH_DOCS += technical/platform-support
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@ -18,6 +18,7 @@ articles = [
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'multi-pack-index.adoc',
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'packfile-uri.adoc',
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'pack-heuristics.adoc',
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'paint-down-to-common.adoc',
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'parallel-checkout.adoc',
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'partial-clone.adoc',
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'platform-support.adoc',
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@ -0,0 +1,154 @@
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Merge-Base Computation and paint_down_to_common()
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==================================================
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The function `paint_down_to_common()` in `commit-reach.c` computes merge
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bases by walking the commit graph backwards from two sets of tips and
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finding where their ancestry meets.
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Use cases
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---------
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Computing merge bases is used in two different ways:
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1. *Finding all merge bases* (`merge-base --all`, `merge-tree`,
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`merge`, `rebase`). A merge base is a common ancestor that is
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not itself an ancestor of another common ancestor.
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2. *Ancestry checks* (`in_merge_bases`, used by `merge-base
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--is-ancestor`, `branch -d`, `fetch`). These ask: "is commit A
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an ancestor of commit B?" If a common ancestor equals one of the
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inputs, that input is necessarily the only merge base -- no other
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common ancestor can be both as recent and not an ancestor of it.
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Both use cases share the same algorithm and implementation.
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Algorithm
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---------
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Given a commit `one` and a set of commits `twos[]`, the walk paints
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commits with two colors:
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- PARENT1: reachable from `one`
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- PARENT2: reachable from any commit in `twos[]`
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The walk uses a priority queue ordered by generation number
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(highest first), breaking ties by commit date. Each step dequeues
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the highest-priority commit (this is when we say a commit is
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"visited") and propagates its paint flags to its parents, enqueuing
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them if they gained new flags. When a commit receives both PARENT1
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and PARENT2, it is a merge-base candidate. A candidate gains the
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STALE flag so its ancestors propagate staleness -- any deeper common
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ancestor is necessarily redundant.
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[[generation-regions]]
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INFINITY and finite generation regions
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--------------------------------------
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The commit-graph stores a generation number for each commit.
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Commits not in the commit-graph have generation
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`GENERATION_NUMBER_INFINITY`. The graph is closed under
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reachability: if a commit is in the graph, all its ancestors are
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too. This partitions the commit graph into two regions:
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....
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+---------------------------------------+
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| INFINITY region |
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| generation = INFINITY |
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| queue order: heuristic (commit date) |
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+---------------------------------------+
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|
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v
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+---------------------------------------+
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| Finite region |
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| generation = finite |
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| queue order: topological |
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+---------------------------------------+
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....
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When the commit-graph is enabled, the INFINITY region is typically
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very small -- it only contains commits added since the last
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commit-graph refresh.
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All reachable INFINITY-generation commits are visited before any
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finite-generation commit, because INFINITY is larger than any finite
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value. Once the walk crosses into the finite region, it stays there.
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In the finite region, generation ordering guarantees topological
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traversal: children are always visited before their parents. This
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means that paint on already-visited commits is final -- no future
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traversal step can add paint to them.
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In the INFINITY region, all commits share the same generation
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value, so the queue breaks ties by commit date. This can violate
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topological ordering: a parent with a later date can be visited
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before a child with an earlier date. Paint flags are therefore
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NOT final at visit time, and a commit visited with only one
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side's paint may later gain the other.
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Paint flags are only added, never removed. Since each flag can be set
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at most once per commit, the number of times a commit can be
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re-enqueued is bounded by the number of flag transitions.
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Termination
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-----------
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The walk tracks the number of commits of each type in the queue
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(PARENT1-only, PARENT2-only, pending merge-base). The main loop
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ends when one of the following conditions holds:
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1. The queue is empty.
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2. The queue contains only stale entries.
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3. Generation cutoff: the dequeued commit's generation is below
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a caller-supplied `min_generation` threshold.
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4. Single result: the caller only needs one merge base, one has
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been found, and the walk has entered the finite-generation
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region.
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5. Side exhaustion: no pure PARENT1 or pure PARENT2 commits
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remain in the queue, no pending merge-base candidates exist,
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and the walk has entered the finite-generation region.
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Stale entry condition
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~~~~~~~~~~~~~~~~~~~~~
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Once all queued entries are stale, no new merge-base candidates can
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be discovered -- that requires at least one non-stale commit from
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each side meeting. Continuing the walk could still invalidate
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existing candidates by proving one is an ancestor of another, but
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`remove_redundant()` handles that as a post-processing step, so it
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is safe to exit early.
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Side-exhaustion condition
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~~~~~~~~~~~~~~~~~~~~~~~~~
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A new merge-base requires commits from both sides to meet. When one
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side's exclusive counter reaches zero and there are no pending
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merge-base candidates, no future traversal step can produce a new
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candidate.
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This optimization only activates in the finite-generation region
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where topological ordering holds. In that region, children are
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always visited before parents, so paint flags are final at visit
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time and an exhausted side cannot reappear. In the INFINITY region,
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commit-date ordering can violate this guarantee, so the check is
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skipped.
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Generation cutoff
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~~~~~~~~~~~~~~~~~
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Some callers (notably `remove_redundant()`) supply a `min_generation`
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threshold -- the minimum generation of the input commits. No merge
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base can have a generation below this threshold, so the walk
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terminates as soon as it dequeues such a commit.
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Single result
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~~~~~~~~~~~~~
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When only one merge base is needed, the walk is in the
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finite-generation region, and the queue uses generation ordering,
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the first candidate found is necessarily the highest-generation
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common ancestor. No remaining commit in the queue can be a
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descendant of this candidate (generation ordering guarantees
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children are visited first), so it cannot be redundant and the walk
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can stop immediately.
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Related documentation
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---------------------
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- `Documentation/technical/commit-graph.adoc` -- generation numbers
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and the reachability closure property.
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@ -793,17 +793,6 @@ int generation_numbers_enabled(struct repository *r)
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return !!first_generation;
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}
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int corrected_commit_dates_enabled(struct repository *r)
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{
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struct commit_graph *g;
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g = prepare_commit_graph(r);
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if (!g || !g->num_commits)
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return 0;
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return g->read_generation_data;
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}
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struct bloom_filter_settings *get_bloom_filter_settings(struct repository *r)
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{
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struct commit_graph *g;
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@ -136,12 +136,6 @@ struct commit_graph *parse_commit_graph(struct repository *r,
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*/
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int generation_numbers_enabled(struct repository *r);
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/*
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* Return 1 if and only if the repository has a commit-graph
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* file and generation data chunk has been written for the file.
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*/
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int corrected_commit_dates_enabled(struct repository *r);
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struct bloom_filter_settings *get_bloom_filter_settings(struct repository *r);
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enum commit_graph_write_flags {
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|
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156
commit-reach.c
156
commit-reach.c
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@ -11,6 +11,7 @@
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#include "tag.h"
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#include "commit-reach.h"
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#include "ewah/ewok.h"
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#include "trace2.h"
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/* Remember to update object flag allocation in object.h */
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#define PARENT1 (1u<<16)
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@ -78,25 +79,105 @@ static void clear_nonstale_queue(struct nonstale_queue *queue)
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queue->max_nonstale = NULL;
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}
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static void nonstale_queue_put_dedup(struct nonstale_queue *queue,
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struct commit *c)
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/*
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* Priority queue with per-side commit counters for paint_down_to_common().
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* Each non-stale queued commit occupies exactly one bucket: PARENT1-only,
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* PARENT2-only, or both (a pending merge-base candidate).
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*/
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struct paint_state {
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struct prio_queue queue;
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size_t parent1_count;
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size_t parent2_count;
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size_t mb_candidate_count;
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timestamp_t min_generation;
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timestamp_t last_gen;
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};
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static void paint_count_update(struct paint_state *state,
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unsigned flags, int delta)
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{
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if (c->object.flags & ENQUEUED)
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return;
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c->object.flags |= ENQUEUED;
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nonstale_queue_put(queue, c);
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switch (flags & (PARENT1 | PARENT2 | STALE)) {
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case PARENT1:
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state->parent1_count += delta;
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break;
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case PARENT2:
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state->parent2_count += delta;
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break;
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case PARENT1 | PARENT2:
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state->mb_candidate_count += delta;
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break;
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case PARENT1 | PARENT2 | STALE:
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break;
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default:
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BUG("unexpected paint state");
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}
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}
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static struct commit *nonstale_queue_get_dedup(struct nonstale_queue *queue)
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static void paint_queue_put(struct paint_state *state,
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struct commit *c, unsigned add_flags)
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{
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struct commit *commit = nonstale_queue_get(queue);
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unsigned old_flags = c->object.flags;
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c->object.flags |= add_flags;
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if (commit)
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commit->object.flags &= ~ENQUEUED;
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if (old_flags & ENQUEUED) {
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paint_count_update(state, old_flags, -1);
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paint_count_update(state, c->object.flags, 1);
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} else {
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c->object.flags |= ENQUEUED;
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prio_queue_put(&state->queue, c);
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paint_count_update(state, c->object.flags, 1);
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}
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}
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/*
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* Dequeue the next commit for the paint walk, or return NULL when
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* no more merge bases can be discovered.
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*/
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static struct commit *paint_queue_get(struct paint_state *state)
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{
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struct commit *commit = prio_queue_get(&state->queue);
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timestamp_t generation;
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if (!commit)
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return NULL;
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commit->object.flags &= ~ENQUEUED;
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generation = commit_graph_generation(commit);
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|
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if (state->min_generation && generation > state->last_gen)
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BUG("bad generation skip %"PRItime" > %"PRItime" at %s",
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generation, state->last_gen,
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oid_to_hex(&commit->object.oid));
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state->last_gen = generation;
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/* generation cutoff */
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if (generation < state->min_generation)
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return NULL;
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if (!state->mb_candidate_count) {
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/* only stale entries remain */
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if (!state->parent1_count && !state->parent2_count)
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return NULL;
|
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/* one side is exhausted */
|
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if ((!state->parent1_count || !state->parent2_count) &&
|
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generation < GENERATION_NUMBER_INFINITY)
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return NULL;
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}
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paint_count_update(state, commit->object.flags, -1);
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return commit;
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}
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/* all input commits in one and twos[] must have been parsed! */
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/*
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* See Documentation/technical/paint-down-to-common.adoc
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*
|
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* All input commits in one and twos[] must have been parsed!
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*/
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static int paint_down_to_common(struct repository *r,
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struct commit *one, int n,
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struct commit **twos,
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@ -104,45 +185,36 @@ static int paint_down_to_common(struct repository *r,
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enum merge_base_flags mb_flags,
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struct commit_list **result)
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{
|
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struct nonstale_queue queue = {
|
||||
{ compare_commits_by_gen_then_commit_date }
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/*
|
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* Generation ordering is required for the side-exhaustion and
|
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* single-result early exits, which rely on topological traversal
|
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* order (children visited before parents) in the finite region.
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*/
|
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struct paint_state state = {
|
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.queue = { compare_commits_by_gen_then_commit_date }
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};
|
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struct commit *commit;
|
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int i;
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int gen_ordered = 1;
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timestamp_t last_gen = GENERATION_NUMBER_INFINITY;
|
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int steps = 0;
|
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struct commit_list **tail = result;
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|
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if (!min_generation && !corrected_commit_dates_enabled(r)) {
|
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queue.pq.compare = compare_commits_by_commit_date;
|
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gen_ordered = 0;
|
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}
|
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state.min_generation = min_generation;
|
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state.last_gen = GENERATION_NUMBER_INFINITY;
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|
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one->object.flags |= PARENT1;
|
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if (!n) {
|
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commit_list_append(one, result);
|
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return 0;
|
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}
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nonstale_queue_put_dedup(&queue, one);
|
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paint_queue_put(&state, one, 0);
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||||
|
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for (i = 0; i < n; i++) {
|
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twos[i]->object.flags |= PARENT2;
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nonstale_queue_put_dedup(&queue, twos[i]);
|
||||
}
|
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for (i = 0; i < n; i++)
|
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paint_queue_put(&state, twos[i], PARENT2);
|
||||
|
||||
while (queue.max_nonstale) {
|
||||
struct commit *commit = nonstale_queue_get_dedup(&queue);
|
||||
while ((commit = paint_queue_get(&state))) {
|
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struct commit_list *parents;
|
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int flags;
|
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timestamp_t generation = commit_graph_generation(commit);
|
||||
|
||||
if (min_generation && generation > last_gen)
|
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BUG("bad generation skip %"PRItime" > %"PRItime" at %s",
|
||||
generation, last_gen,
|
||||
oid_to_hex(&commit->object.oid));
|
||||
last_gen = generation;
|
||||
|
||||
if (generation < min_generation)
|
||||
break;
|
||||
steps++;
|
||||
|
||||
flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
|
||||
if (flags == (PARENT1 | PARENT2)) {
|
||||
|
|
@ -155,8 +227,7 @@ static int paint_down_to_common(struct repository *r,
|
|||
* descendant of this one.
|
||||
*/
|
||||
if (!(mb_flags & MERGE_BASE_FIND_ALL) &&
|
||||
gen_ordered &&
|
||||
generation < GENERATION_NUMBER_INFINITY)
|
||||
state.last_gen < GENERATION_NUMBER_INFINITY)
|
||||
break;
|
||||
}
|
||||
/* Mark parents of a found merge stale */
|
||||
|
|
@ -169,7 +240,7 @@ static int paint_down_to_common(struct repository *r,
|
|||
if ((p->object.flags & flags) == flags)
|
||||
continue;
|
||||
if (repo_parse_commit(r, p)) {
|
||||
clear_nonstale_queue(&queue);
|
||||
clear_prio_queue(&state.queue);
|
||||
commit_list_free(*result);
|
||||
*result = NULL;
|
||||
/*
|
||||
|
|
@ -184,12 +255,13 @@ static int paint_down_to_common(struct repository *r,
|
|||
return error(_("could not parse commit %s"),
|
||||
oid_to_hex(&p->object.oid));
|
||||
}
|
||||
p->object.flags |= flags;
|
||||
nonstale_queue_put_dedup(&queue, p);
|
||||
paint_queue_put(&state, p, flags);
|
||||
}
|
||||
}
|
||||
|
||||
clear_nonstale_queue(&queue);
|
||||
clear_prio_queue(&state.queue);
|
||||
trace2_data_intmax("paint_down_to_common", r,
|
||||
"steps", steps);
|
||||
commit_list_sort_by_date(result);
|
||||
return 0;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -797,6 +797,7 @@ integration_tests = [
|
|||
't6041-bisect-submodule.sh',
|
||||
't6050-replace.sh',
|
||||
't6060-merge-index.sh',
|
||||
't6099-merge-base-side-exhaustion.sh',
|
||||
't6100-rev-list-in-order.sh',
|
||||
't6101-rev-parse-parents.sh',
|
||||
't6102-rev-list-unexpected-objects.sh',
|
||||
|
|
|
|||
|
|
@ -0,0 +1,82 @@
|
|||
#!/bin/sh
|
||||
|
||||
test_description='merge-base with ancestor among merge-base candidates
|
||||
|
||||
Test that merge-base --all correctly handles cases where
|
||||
multiple merge-base candidates exist and one is an ancestor
|
||||
of another. The side-exhaustion optimization in
|
||||
paint_down_to_common may exit before STALE propagation
|
||||
removes the ancestor, but remove_redundant catches it.
|
||||
|
||||
Graph shape (parents are below children):
|
||||
|
||||
A ----------- X
|
||||
|\ /|
|
||||
| B---------/ |
|
||||
| | |
|
||||
e2 \ f2
|
||||
| | |
|
||||
e1 d1 f1
|
||||
\ | /
|
||||
\ | /
|
||||
\| /
|
||||
C
|
||||
|
||||
A and X are the two tips.
|
||||
B and C are both reachable from A and X.
|
||||
B reaches C through d1.
|
||||
Only B should appear in merge-base --all output.
|
||||
'
|
||||
|
||||
GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
|
||||
export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
|
||||
|
||||
TEST_PASSES_SANITIZE_LEAK=true
|
||||
. ./test-lib.sh
|
||||
|
||||
test_expect_success 'setup ancestor merge-base candidate' '
|
||||
test_commit C &&
|
||||
|
||||
git checkout -b d-chain HEAD &&
|
||||
test_commit d1 &&
|
||||
test_commit B &&
|
||||
|
||||
git checkout -b e-path C &&
|
||||
test_commit e1 &&
|
||||
test_commit e2 &&
|
||||
|
||||
git checkout -b f-path C &&
|
||||
test_commit f1 &&
|
||||
test_commit f2 &&
|
||||
|
||||
git checkout -b branch-A e-path &&
|
||||
test_merge A B &&
|
||||
|
||||
git checkout -b branch-X f-path &&
|
||||
test_merge X B &&
|
||||
|
||||
git commit-graph write --reachable
|
||||
'
|
||||
|
||||
test_expect_success 'merge-base --all excludes ancestor candidate' '
|
||||
git rev-parse B >expected &&
|
||||
git merge-base --all A X >actual &&
|
||||
test_cmp expected actual
|
||||
'
|
||||
|
||||
test_expect_success 'merge-base (single) finds shallowest' '
|
||||
git rev-parse B >expected &&
|
||||
git merge-base A X >actual &&
|
||||
test_cmp expected actual
|
||||
'
|
||||
|
||||
# Without commit-graph: generation numbers are INFINITY,
|
||||
# side-exhaustion optimization does not fire.
|
||||
test_expect_success 'merge-base --all without commit-graph' '
|
||||
rm -f .git/objects/info/commit-graph &&
|
||||
git rev-parse B >expected &&
|
||||
git merge-base --all A X >actual &&
|
||||
test_cmp expected actual
|
||||
'
|
||||
|
||||
test_done
|
||||
|
|
@ -85,6 +85,103 @@ test_expect_success 'setup' '
|
|||
git branch -f skew-P2 "$skew_P2" &&
|
||||
git tag skew-M2 "$skew_M2" &&
|
||||
|
||||
# Build a small side topology to exercise the (PARENT1|PARENT2) ->
|
||||
# (PARENT1|PARENT2|STALE) transition in paint_down_to_common(); the
|
||||
# 10x10 grid above does not exercise it because no merge-base candidate
|
||||
# there is a descendant of another, so STALE never reaches a
|
||||
# still-pending candidate.
|
||||
#
|
||||
# ps-X
|
||||
# /|\
|
||||
# / | \
|
||||
# ps-Z ps-B ps-W
|
||||
# | / \ |
|
||||
# | / \ |
|
||||
# |/ \|
|
||||
# ps-T1 ps-T2
|
||||
#
|
||||
# where ps-T1=merge(ps-Z,ps-B), ps-T2=merge(ps-W,ps-B), so
|
||||
# merge-base(ps-T1,ps-T2) = ps-B. During the walk, ps-X transitions
|
||||
# to (PARENT1|PARENT2) via ps-Z and ps-W before ps-B is dequeued;
|
||||
# then the STALE-walk from ps-B transitions ps-X to
|
||||
# (PARENT1|PARENT2|STALE).
|
||||
git checkout --orphan ps-orphan &&
|
||||
test_commit ps-X &&
|
||||
git checkout -b ps-B-br ps-X && test_commit ps-B &&
|
||||
git checkout -b ps-Z-br ps-X && test_commit ps-Z &&
|
||||
git checkout -b ps-W-br ps-X && test_commit ps-W &&
|
||||
git checkout -b ps-T1 ps-Z &&
|
||||
git merge --no-ff -m ps-T1 ps-B &&
|
||||
git checkout -b ps-T2 ps-W &&
|
||||
git merge --no-ff -m ps-T2 ps-B &&
|
||||
|
||||
# Build a side topology that lives entirely outside the half
|
||||
# commit-graph and has non-monotonic commit dates, to exercise the
|
||||
# INFINITY-gate in paint_down_to_common. With both tips outside
|
||||
# the graph, generation is INFINITY and the queue falls back to
|
||||
# commit-date order, which here is non-monotonic.
|
||||
#
|
||||
# pi-X (date 500, PARENT1 tip) --> pi-P, pi-D
|
||||
# pi-D (date 480) --> pi-C
|
||||
# pi-C (date 200) --> pi-B
|
||||
# pi-B (date 100, PARENT2 tip) --> pi-P
|
||||
# pi-P (date 450, root)
|
||||
#
|
||||
# merge-base(pi-X, pi-B) = pi-B (it is an ancestor of pi-X and is
|
||||
# itself one of the queried tips).
|
||||
git checkout --orphan pi-orphan &&
|
||||
test_commit --date "@450 +0000" pi-P &&
|
||||
test_commit --date "@100 +0000" pi-B &&
|
||||
test_commit --date "@200 +0000" pi-C &&
|
||||
test_commit --date "@480 +0000" pi-D &&
|
||||
GIT_AUTHOR_DATE="@500 +0000" GIT_COMMITTER_DATE="@500 +0000" \
|
||||
git commit-tree -p pi-D -p pi-P -m pi-X pi-D^{tree} >pi-X-oid &&
|
||||
pi_x="$(cat pi-X-oid)" &&
|
||||
git branch -f pi-X-br "$pi_x" &&
|
||||
git tag pi-X "$pi_x" &&
|
||||
|
||||
# Clock-skew topology for side-exhaustion testing.
|
||||
# D is the correct merge base but has a higher committer date
|
||||
# than C (its child). With date ordering, D would be dequeued
|
||||
# before C, causing side-exhaustion to fire too early.
|
||||
# Generation ordering prevents this by visiting children
|
||||
# before parents regardless of dates.
|
||||
#
|
||||
# se-A (date 7000) --> se-C (date 3000) --> se-D (date 5000) --> se-root (date 4000)
|
||||
# se-B (date 6000) --> se-D
|
||||
#
|
||||
se_root=$(skew_commit 4000 se-root) &&
|
||||
se_D=$(skew_commit 5000 se-D -p "$se_root") &&
|
||||
se_C=$(skew_commit 3000 se-C -p "$se_D") &&
|
||||
se_A=$(skew_commit 7000 se-A -p "$se_C") &&
|
||||
se_B=$(skew_commit 6000 se-B -p "$se_D") &&
|
||||
git branch -f se-A "$se_A" &&
|
||||
git branch -f se-B "$se_B" &&
|
||||
git tag se-D "$se_D" &&
|
||||
|
||||
# Clock-skew topology with redundant ancestor for
|
||||
# side-exhaustion testing. MB1 is the correct merge base;
|
||||
# MB2 is its parent. A reaches MB2 via E (high date) and
|
||||
# MB1 via C (low date). B reaches MB1 via D. With date
|
||||
# ordering, side-exhaustion would fire before C is dequeued,
|
||||
# missing MB1. Generation ordering ensures both are found.
|
||||
#
|
||||
# se2-A (date 8000) --> se2-C (date 2000) --> se2-MB1 (date 5000) --> se2-MB2 (date 4000) --> se2-root (date 1000)
|
||||
# se2-A --> se2-E (date 6500) --> se2-MB2
|
||||
# se2-B (date 7000) --> se2-D (date 6000) --> se2-MB1
|
||||
#
|
||||
se2_root=$(skew_commit 1000 se2-root) &&
|
||||
se2_MB2=$(skew_commit 4000 se2-MB2 -p "$se2_root") &&
|
||||
se2_MB1=$(skew_commit 5000 se2-MB1 -p "$se2_MB2") &&
|
||||
se2_C=$(skew_commit 2000 se2-C -p "$se2_MB1") &&
|
||||
se2_D=$(skew_commit 6000 se2-D -p "$se2_MB1") &&
|
||||
se2_E=$(skew_commit 6500 se2-E -p "$se2_MB2") &&
|
||||
se2_A=$(skew_commit 8000 se2-A -p "$se2_C" -p "$se2_E") &&
|
||||
se2_B=$(skew_commit 7000 se2-B -p "$se2_D") &&
|
||||
git branch -f se2-A "$se2_A" &&
|
||||
git branch -f se2-B "$se2_B" &&
|
||||
git tag se2-MB1 "$se2_MB1" &&
|
||||
|
||||
git commit-graph write --reachable &&
|
||||
mv .git/objects/info/commit-graph commit-graph-full &&
|
||||
chmod u+w commit-graph-full &&
|
||||
|
|
@ -98,24 +195,34 @@ test_expect_success 'setup' '
|
|||
'
|
||||
|
||||
run_all_modes () {
|
||||
test_when_finished rm -rf .git/objects/info/commit-graph &&
|
||||
"$@" <input >actual &&
|
||||
test_cmp expect actual &&
|
||||
cp commit-graph-full .git/objects/info/commit-graph &&
|
||||
"$@" <input >actual &&
|
||||
test_cmp expect actual &&
|
||||
cp commit-graph-half .git/objects/info/commit-graph &&
|
||||
"$@" <input >actual &&
|
||||
test_cmp expect actual &&
|
||||
cp commit-graph-no-gdat .git/objects/info/commit-graph &&
|
||||
"$@" <input >actual &&
|
||||
test_cmp expect actual
|
||||
graph=.git/objects/info/commit-graph &&
|
||||
test_when_finished rm -rf "$graph" "${graph}s" &&
|
||||
rm -f trace-mode-*.txt &&
|
||||
|
||||
for mode in none full half no-gdat
|
||||
do
|
||||
rm -rf "$graph" "${graph}s" &&
|
||||
cp "commit-graph-${mode}" "$graph" 2>/dev/null ||
|
||||
true &&
|
||||
GIT_TRACE2_EVENT="$(pwd)/trace-mode-${mode}.txt" \
|
||||
"$@" <input >actual &&
|
||||
test_cmp expect actual || return 1
|
||||
done
|
||||
}
|
||||
|
||||
test_all_modes () {
|
||||
run_all_modes test-tool reach "$@"
|
||||
}
|
||||
|
||||
test_paint_down_steps () {
|
||||
for mode in none full half no-gdat
|
||||
do
|
||||
test_trace2_data_singular paint_down_to_common steps "$1" \
|
||||
"mode=$mode" <"trace-mode-${mode}.txt" || return 1
|
||||
shift
|
||||
done
|
||||
}
|
||||
|
||||
test_expect_success 'ref_newer:miss' '
|
||||
cat >input <<-\EOF &&
|
||||
A:commit-5-7
|
||||
|
|
@ -182,6 +289,17 @@ test_expect_success 'in_merge_bases_many:miss-heuristic' '
|
|||
test_all_modes in_merge_bases_many
|
||||
'
|
||||
|
||||
test_expect_success 'in_merge_bases_many:self' '
|
||||
cat >input <<-\EOF &&
|
||||
A:commit-6-8
|
||||
X:commit-5-9
|
||||
X:commit-6-8
|
||||
EOF
|
||||
echo "in_merge_bases_many(A,X):1" >expect &&
|
||||
test_all_modes in_merge_bases_many &&
|
||||
test_paint_down_steps 45 1 25 1
|
||||
'
|
||||
|
||||
test_expect_success 'is_descendant_of:hit' '
|
||||
cat >input <<-\EOF &&
|
||||
A:commit-5-7
|
||||
|
|
@ -219,6 +337,105 @@ test_expect_success 'get_merge_bases_many' '
|
|||
test_all_modes get_merge_bases_many
|
||||
'
|
||||
|
||||
test_expect_success 'get_merge_bases_many:duplicate-twos' '
|
||||
cat >input <<-\EOF &&
|
||||
A:commit-5-7
|
||||
X:commit-4-8
|
||||
X:commit-4-8
|
||||
X:commit-6-6
|
||||
X:commit-6-6
|
||||
X:commit-8-3
|
||||
EOF
|
||||
{
|
||||
echo "get_merge_bases_many(A,X):" &&
|
||||
git rev-parse commit-5-6 \
|
||||
commit-4-7 | sort
|
||||
} >expect &&
|
||||
test_all_modes get_merge_bases_many
|
||||
'
|
||||
|
||||
test_expect_success 'get_merge_bases_many:pending-stale' '
|
||||
# Exercises the (PARENT1|PARENT2) -> (...|STALE) transition path in
|
||||
# paint_down_to_common(). See the topology comment in the setup test.
|
||||
cat >input <<-\EOF &&
|
||||
A:ps-T1
|
||||
X:ps-T2
|
||||
EOF
|
||||
{
|
||||
echo "get_merge_bases_many(A,X):" &&
|
||||
git rev-parse ps-B
|
||||
} >expect &&
|
||||
test_all_modes get_merge_bases_many &&
|
||||
test_paint_down_steps 5 5 5 5
|
||||
'
|
||||
|
||||
test_expect_success 'get_merge_bases_many:infinity-both-sides' '
|
||||
# Exercises the push-time INFINITY-gate in paint_down_to_common(). See
|
||||
# the pi-* topology comment in the setup test.
|
||||
cat >input <<-\EOF &&
|
||||
A:pi-X
|
||||
X:pi-B
|
||||
EOF
|
||||
{
|
||||
echo "get_merge_bases_many(A,X):" &&
|
||||
git rev-parse pi-B
|
||||
} >expect &&
|
||||
test_all_modes get_merge_bases_many &&
|
||||
test_paint_down_steps 5 4 5 4
|
||||
'
|
||||
|
||||
test_expect_success 'setup mixed finite/INFINITY topology' '
|
||||
# Create a commit outside all saved commit-graph files so it always
|
||||
# has INFINITY generation, while its parent (ps-X) is in the graph
|
||||
# with a finite generation. Use the ps-* orphan topology so we do
|
||||
# not pollute the grid-based rev-list tests.
|
||||
git checkout ps-X &&
|
||||
test_env GIT_TEST_COMMIT_GRAPH= test_commit pm-INF
|
||||
'
|
||||
|
||||
test_expect_success 'get_merge_bases_many:mixed-finite-infinity' '
|
||||
# One tip (pm-INF) is outside the commit-graph with INFINITY
|
||||
# generation; the other (ps-B) is in the graph with finite
|
||||
# generation. The walk starts in the INFINITY region and crosses
|
||||
# into the finite region where side-exhaustion can fire.
|
||||
cat >input <<-\EOF &&
|
||||
A:pm-INF
|
||||
X:ps-B
|
||||
EOF
|
||||
{
|
||||
echo "get_merge_bases_many(A,X):" &&
|
||||
git rev-parse ps-X
|
||||
} >expect &&
|
||||
test_all_modes get_merge_bases_many &&
|
||||
test_paint_down_steps 3 3 3 3
|
||||
'
|
||||
|
||||
test_expect_success 'merge-base --all commit-walk steps' '
|
||||
>input &&
|
||||
git rev-parse commit-9-1 >expect &&
|
||||
run_all_modes git merge-base --all commit-9-9 commit-9-1 &&
|
||||
test_paint_down_steps 81 9 57 37
|
||||
'
|
||||
|
||||
test_expect_success 'merge-base --all with clock skew (side-exhaustion)' '
|
||||
# Verify that the merge base is computed correctly even
|
||||
# when commits have non-monotonic commit dates.
|
||||
>input &&
|
||||
git rev-parse se-D >expect &&
|
||||
run_all_modes git merge-base --all se-A se-B &&
|
||||
test_paint_down_steps 6 4 6 4
|
||||
'
|
||||
|
||||
test_expect_success 'merge-base --all with clock skew and redundant ancestor (side-exhaustion)' '
|
||||
# Verify that the correct merge base is found even when
|
||||
# non-monotonic commit dates could cause a redundant
|
||||
# ancestor to be visited first.
|
||||
>input &&
|
||||
git rev-parse se2-MB1 >expect &&
|
||||
run_all_modes git merge-base --all se2-A se2-B &&
|
||||
test_paint_down_steps 8 6 8 6
|
||||
'
|
||||
|
||||
test_expect_success 'reduce_heads' '
|
||||
cat >input <<-\EOF &&
|
||||
X:commit-1-10
|
||||
|
|
|
|||
|
|
@ -1996,6 +1996,42 @@ test_trace2_data () {
|
|||
grep -e '"category":"'"$1"'","key":"'"$2"'","value":"'"$3"'"'
|
||||
}
|
||||
|
||||
# Check that the given trace2 data event has the expected value and
|
||||
# appears exactly once. Produces a diagnostic on failure.
|
||||
#
|
||||
# test_trace2_data_singular <category> <key> <value> [<label>]
|
||||
test_trace2_data_singular () {
|
||||
local category="$1" key="$2" expect_val="$3"
|
||||
local label_suffix="${4:+ [$4]}"
|
||||
local kv_pattern='"category":"'"$category"'","key":"'"$key"'","value":"\([^"]*\)"'
|
||||
local actual
|
||||
|
||||
actual=$(sed -n "s|.*${kv_pattern}.*|\1|p") &&
|
||||
|
||||
if test -z "$actual"
|
||||
then
|
||||
echo >&4 "error: trace2 data '$category/$key'$label_suffix not found"
|
||||
return 1
|
||||
fi &&
|
||||
|
||||
case "$actual" in
|
||||
*"
|
||||
"*)
|
||||
echo >&4 "error: trace2 data '$category/$key'$label_suffix has multiple entries, expected 1"
|
||||
printf '%s\n' "$actual" | sed 's/^/ actual: /' >&4
|
||||
return 1
|
||||
;;
|
||||
esac &&
|
||||
|
||||
if test "$actual" != "$expect_val"
|
||||
then
|
||||
echo >&4 "error: trace2 data '$category/$key'$label_suffix"
|
||||
echo >&4 " expected: $expect_val"
|
||||
echo >&4 " actual: $actual"
|
||||
return 1
|
||||
fi
|
||||
}
|
||||
|
||||
# Given a GIT_TRACE2_EVENT log over stdin, writes to stdout a list of URLs
|
||||
# sent to git-remote-https child processes.
|
||||
test_remote_https_urls() {
|
||||
|
|
|
|||
Loading…
Reference in New Issue