Re: [PATCH v5 09/11] commit-graph: use generation v2 only if entire chain does

On 1/10/2021 8:13 AM, Abhishek Kumar wrote:

On Tue, Dec 29, 2020 at 10:23:54PM -0500, Derrick Stolee wrote:

quoted

Your tests in this patch seem very thorough, covering all the cases
I could think to create this strange situation. I even tried creating
cases where the overflow would be necessary. The following test actually
fails on the "graph_read_expect 6" due to the extra chunk, not the 'write'
process I was trying to trick into failure.

diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh
index 8e90f3423b..cfef8e52b9 100755
--- a/t/t5324-split-commit-graph.sh
+++ b/t/t5324-split-commit-graph.sh

@@ -453,6 +453,20 @@ test_expect_success 'prevent regression for duplicate commits across layers' '
        git -C dup commit-graph verify
 '
 
+test_expect_success 'upgrade to generation data succeeds when there was none' '
+	(
+		cd dup &&
+		rm -rf .git/objects/info/commit-graph* &&
+		GIT_TEST_COMMIT_GRAPH_NO_GDAT=1 git commit-graph \
+			write --reachable &&
+		GIT_COMMITTER_DATE="1980-01-01 00:00" git commit --allow-empty -m one &&
+		GIT_COMMITTER_DATE="2090-01-01 00:00" git commit --allow-empty -m two &&
+		GIT_COMMITTER_DATE="2000-01-01 00:00" git commit --allow-empty -m three &&
+		git commit-graph write --reachable &&
+		graph_read_expect 6
+	)
+'

I am not sure what this test adds over the existing generation data
overflow related tests added in t5318-commit-graph.sh

Good point.

-Stolee