[PATCH 1/2] test-lib.sh: set GIT_TRACE2_EVENT_NESTING

["Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com>]

From: Derrick Stolee <dstolee@microsoft.com>

The GIT_TRACE2_EVENT feed has a limited nesting depth to avoid
overloading the feed when recursing into deep paths while adding more
nested regions.

Some tests use the GIT_TRACE2_EVENT feed to look for internal events,
ensuring that intended behavior is happening.

One such example is in t4216-log-bloom.sh which looks for a statistic
given as a trace2_data_intmax() call. This test started failing under
'-x' with 2ca245f8be5 (csum-file.h: increase hashfile buffer size,
2021-05-18) because the change in stderr triggered the progress API to
create an extra trace2 region, ejecting the statistic.

This change increases the value of GIT_TRACE2_EVENT_NESTING across the
entire test suite to avoid errors like this. Future changes will remove
custom assignments of GIT_TRACE2_EVENT_NESTING from some test scripts
that were aware of this limitation.

Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
---
 t/test-lib.sh | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/t/test-lib.sh b/t/test-lib.sh
index 2679a7596a6..2e815c41c8f 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -476,6 +476,13 @@ export GIT_TEST_MERGE_ALGORITHM
 GIT_TRACE_BARE=1
 export GIT_TRACE_BARE
 
+# Some tests scan the GIT_TRACE2_EVENT feed for events, but the
+# default depth is 2, which frequently causes issues when the
+# events are wrapped in new regions. Set it to a sufficiently
+# large depth to avoid custom changes in the test suite.
+GIT_TRACE2_EVENT_NESTING=100
+export GIT_TRACE2_EVENT_NESTING
+
 # Use specific version of the index file format
 if test -n "${GIT_TEST_INDEX_VERSION:+isset}"
 then
-- 
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