Fix assorted bugs by changing TS_execute's callback API to ternary logic.

Text search sometimes failed to find valid matches, for instance
'!crew:A'::tsquery might fail to locate 'crew:1B'::tsvector during
an index search.  The root of the issue is that TS_execute's callback
functions were not changed to use ternary (yes/no/maybe) reporting
when we made the search logic itself do so.  It's somewhat annoying
to break that API, but on the other hand we now see that any code
using plain boolean logic is almost certainly broken since the
addition of phrase search.  There seem to be very few outside callers
of this code anyway, so we'll just break them intentionally to get
them to adapt.

This allows removal of tsginidx.c's private re-implementation of
TS_execute, since that's now entirely duplicative.  It's also no
longer necessary to avoid use of CALC_NOT in tsgistidx.c, since
the underlying callbacks can now do something reasonable.

Back-patch into v13.  We can't change this in stable branches,
but it seems not quite too late to fix it in v13.

Tom Lane and Pavel Borisov

Discussion: https://postgr.es/m/CALT9ZEE-aLotzBg-pOp2GFTesGWVYzXA3=mZKzRDa_OKnLF7Mg@mail.gmail.com

1 files changed, 16 insertions, 10 deletions

diff --git a/src/backend/utils/adt/tsgistidx.c b/src/backend/utils/adt/tsgistidx.c
index c3f25800e7b..927aed91564 100644
--- a/src/backend/utils/adt/tsgistidx.c
+++ b/src/backend/utils/adt/tsgistidx.c
@@ -273,9 +273,9 @@ typedef struct
 } CHKVAL;
 
 /*
- * is there value 'val' in array or not ?
+ * TS_execute callback for matching a tsquery operand to GIST leaf-page data
  */
-static bool
+static TSTernaryValue
 checkcondition_arr(void *checkval, QueryOperand *val, ExecPhraseData *data)
 {
 	int32	   *StopLow = ((CHKVAL *) checkval)->arrb;
@@ -288,23 +288,26 @@ checkcondition_arr(void *checkval, QueryOperand *val, ExecPhraseData *data)
 	 * we are not able to find a prefix by hash value
 	 */
 	if (val->prefix)
-		return true;
+		return TS_MAYBE;
 
 	while (StopLow < StopHigh)
 	{
 		StopMiddle = StopLow + (StopHigh - StopLow) / 2;
 		if (*StopMiddle == val->valcrc)
-			return true;
+			return TS_MAYBE;
 		else if (*StopMiddle < val->valcrc)
 			StopLow = StopMiddle + 1;
 		else
 			StopHigh = StopMiddle;
 	}
 
-	return false;
+	return TS_NO;
 }
 
-static bool
+/*
+ * TS_execute callback for matching a tsquery operand to GIST non-leaf data
+ */
+static TSTernaryValue
 checkcondition_bit(void *checkval, QueryOperand *val, ExecPhraseData *data)
 {
 	void	   *key = (SignTSVector *) checkval;
@@ -313,8 +316,12 @@ checkcondition_bit(void *checkval, QueryOperand *val, ExecPhraseData *data)
 	 * we are not able to find a prefix in signature tree
 	 */
 	if (val->prefix)
-		return true;
-	return GETBIT(GETSIGN(key), HASHVAL(val->valcrc, GETSIGLEN(key)));
+		return TS_MAYBE;
+
+	if (GETBIT(GETSIGN(key), HASHVAL(val->valcrc, GETSIGLEN(key))))
+		return TS_MAYBE;
+	else
+		return TS_NO;
 }
 
 Datum
@@ -339,10 +346,9 @@ gtsvector_consistent(PG_FUNCTION_ARGS)
 		if (ISALLTRUE(key))
 			PG_RETURN_BOOL(true);
 
-		/* since signature is lossy, cannot specify CALC_NOT here */
 		PG_RETURN_BOOL(TS_execute(GETQUERY(query),
 								  key,
-								  TS_EXEC_PHRASE_NO_POS,
+								  TS_EXEC_PHRASE_NO_POS | TS_EXEC_CALC_NOT,
 								  checkcondition_bit));
 	}
 	else