Remove misleading read stream asserts in a few users

melanieplageman · melanieplageman · commit 54a3615f15b9 · 2025-04-03T18:22:37.000-04:00
Several read stream users asserted that the read stream was exhausted after looping on that very condition. It was pointed out in an a review of an as-of-yet uncommitted read stream user [1] that this was confusing and could lead the reader to think there was a possibility of some kind of race condition. Remove these asserts. [1] https://postgr.es/m/F9ACE8D0-B807-4A17-B6BD-87EF0717983D%40yesql.se
diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
@@ -853,8 +853,6 @@ verify_heapam(PG_FUNCTION_ARGS)
 			break;
 	}
 
-	/* Ensure that the stream is completely read */
-	Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
 	read_stream_end(stream);
 
 	if (vmbuffer != InvalidBuffer)
diff --git a/src/backend/access/gist/gistvacuum.c b/src/backend/access/gist/gistvacuum.c
@@ -254,8 +254,6 @@ gistvacuumscan(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
 			gistvacuumpage(&vstate, buf);
 		}
 
-		Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
-
 		/*
 		 * We have to reset the read stream to use it again. After returning
 		 * InvalidBuffer, the read stream API won't invoke our callback again
diff --git a/src/backend/access/nbtree/nbtree.c b/src/backend/access/nbtree/nbtree.c
@@ -1117,8 +1117,6 @@ btvacuumscan(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
 											 current_block);
 		}
 
-		Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
-
 		/*
 		 * We have to reset the read stream to use it again. After returning
 		 * InvalidBuffer, the read stream API won't invoke our callback again
diff --git a/src/backend/access/spgist/spgvacuum.c b/src/backend/access/spgist/spgvacuum.c
@@ -879,8 +879,6 @@ spgvacuumscan(spgBulkDeleteState *bds)
 				spgprocesspending(bds);
 		}
 
-		Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);
-
 		/*
 		 * We have to reset the read stream to use it again. After returning
 		 * InvalidBuffer, the read stream API won't invoke our callback again

Original file line number	Diff line number	Diff line change
`@@ -853,8 +853,6 @@ verify_heapam(PG_FUNCTION_ARGS)`
`853`	`853`	`break;`
`854`	`854`	`}`
`855`	`855`
`856`		`- /* Ensure that the stream is completely read */`
`857`		`- Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);`
`858`	`856`	`read_stream_end(stream);`
`859`	`857`
`860`	`858`	`if (vmbuffer != InvalidBuffer)`
Original file line number	Diff line number	Diff line change
`@@ -254,8 +254,6 @@ gistvacuumscan(IndexVacuumInfo info, IndexBulkDeleteResult stats,`
`254`	`254`	`gistvacuumpage(&vstate, buf);`
`255`	`255`	`}`
`256`	`256`
`257`		`- Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);`
`258`		`-`
`259`	`257`	`/*`
`260`	`258`	`* We have to reset the read stream to use it again. After returning`
`261`	`259`	`* InvalidBuffer, the read stream API won't invoke our callback again`
Original file line number	Diff line number	Diff line change
`@@ -1117,8 +1117,6 @@ btvacuumscan(IndexVacuumInfo info, IndexBulkDeleteResult stats,`
`1117`	`1117`	`current_block);`
`1118`	`1118`	`}`
`1119`	`1119`
`1120`		`- Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);`
`1121`		`-`
`1122`	`1120`	`/*`
`1123`	`1121`	`* We have to reset the read stream to use it again. After returning`
`1124`	`1122`	`* InvalidBuffer, the read stream API won't invoke our callback again`
Original file line number	Diff line number	Diff line change
`@@ -879,8 +879,6 @@ spgvacuumscan(spgBulkDeleteState *bds)`
`879`	`879`	`spgprocesspending(bds);`
`880`	`880`	`}`
`881`	`881`
`882`		`- Assert(read_stream_next_buffer(stream, NULL) == InvalidBuffer);`
`883`		`-`
`884`	`882`	`/*`
`885`	`883`	`* We have to reset the read stream to use it again. After returning`
`886`	`884`	`* InvalidBuffer, the read stream API won't invoke our callback again`