test: the object-storage loops name the case each iteration tests (#982, 2 of 8)

CHANGELOG.md

@@ -1848,6 +1848,45 @@ true until the next version shipped.
   `moved s4d1's layout`, `no row was lost from s4d2` -- for the same reason.
 
   No ledger change: `hilbert_cluster` is not one of the two suites the ledger covers.
+- The object-storage loops name the case each iteration tests, so six checks stop
+  sharing three ledger keys (#982, second of eight).
+
+  `objstore_module` lost the most records of any suite to key collapsing: two loops of
+  three iterations each, where the check names did not carry the thing the iteration
+  varies. Measured against a control run on clean `main`:
+
+      clean main    30 records   24 distinct keys   3 colliding   6 lost
+      this branch   30 records   30 distinct keys   0 colliding   0 lost
+
+  The record count is unchanged, so this adds and removes no checks.
+
+  **The two loops show both sub-shapes of the same defect.** In the first, the headline
+  already interpolated the scheme and only the continuation was short:
+
+      check     "a s3 URL reports an object-storage error, not a missing file"
+      check_num "and does NOT report it as a missing file"      <- identical three times
+
+  In the second, *neither* name carried the metacharacter, so three iterations produced
+  one key for each of **two** checks -- the headline collided as well.
+
+  Both are fixed by the rule #984 proposed: the continuation carries the same
+  discriminator its headline names, and where the headline does not name one either, it
+  gains it. The discriminators come from the loop variable by parameter expansion
+  (`${url%%:*}` and stripping the fixed prefix and suffix off the pattern), so they are
+  already in scope:
+
+      a remote glob (*) is handled remotely (an object-storage error, not a local one)
+      and the * glob is NOT reported as a local filesystem miss
+      and the https URL is NOT reported as a missing file
+
+  The first loop's headline now reads its scheme from a variable rather than a `cut`
+  subshell, because both names need it. The resulting check name is byte-identical, so
+  no ledger row moves on account of it.
+
+  No ledger change at all: `objstore_module` is not one of the two suites the ledger
+  covers, so its check names have no rows. That is also why the twenty-four collisions
+  matter for #432 rather than for the census today -- twenty-one of them are in suites
+  that become covered only when the 240 are seeded.
 
 ## [1.0-alpha3] - 2026-09-02
 

test/objstore_module.sh

@@ -102,10 +102,14 @@ check_num "positive control: it IS defined in the module, so nm really looked" \
 
 # A remote path must report a remote error, from the reader, without a connection.
 for url in "s3://bucket/key.parquet" "gs://bucket/key.parquet" "https://host/key.parquet"; do
+	# The scheme, by parameter expansion rather than a `cut` subshell, because BOTH
+	# names need it now: the headline already carried it and the continuation did not,
+	# which is why three iterations produced one ledger key (#982).
+	scheme="${url%%:*}"
 	out=$(psql_run "SELECT * FROM pgcolumnar.read_parquet('$url') AS (a int)" 2>&1)
-	check "a $(cut -d: -f1 <<<"$url") URL reports an object-storage error, not a missing file" \
+	check "a $scheme URL reports an object-storage error, not a missing file" \
 		"$([ "$(grep -c 'object storage is not implemented\|is not supported\|requires the object-store module\|requires AWS_\|could not resolve\|could not connect\|objstore_allowed_endpoints' <<<"$out")" -ge 1 ] && echo yes || echo no)" "yes"
-	check_num "and does NOT report it as a missing file" \
+	check_num "and the $scheme URL is NOT reported as a missing file" \
 		"$(grep -c 'No such file or directory' <<<"$out")" "0"
 done
 
@@ -119,10 +123,15 @@ done
 # storage error, and the invariant this arm still guards is that it is NEVER a
 # local filesystem miss. `*`, `?` and `[` are all legal in an S3 key.
 for pat in "s3://bucket/a*.parquet" "s3://bucket/a?.parquet" "s3://bucket/a[0-9].parquet"; do
+	# The metacharacter under test, which is what distinguishes the three iterations.
+	# Here BOTH names collided: unlike the loop above, the headline did not carry it
+	# either, so three iterations produced one key for each of two checks (#982).
+	meta="${pat#s3://bucket/a}"
+	meta="${meta%.parquet}"
 	out=$(psql_run "SELECT * FROM pgcolumnar.read_parquet('$pat') AS (a int)" 2>&1)
-	check "a remote glob is handled remotely (an object-storage error, not a local one)" \
+	check "a remote glob ($meta) is handled remotely (an object-storage error, not a local one)" \
 		"$([ "$(grep -c 'requires AWS_\|object storage\|objstore_allowed_endpoints\|requires the object-store module\|could not resolve\|could not connect\|is not in pgcolumnar' <<<"$out")" -ge 1 ] && echo yes || echo no)" "yes"
-	check_num "and it is NOT reported as a local filesystem miss" \
+	check_num "and the $meta glob is NOT reported as a local filesystem miss" \
 		"$(grep -c 'no files match pattern\|matched no regular files\|No such file or directory' <<<"$out")" "0"
 done