Index: ext/fts5/fts5_aux.c ================================================================== --- ext/fts5/fts5_aux.c +++ ext/fts5/fts5_aux.c @@ -355,10 +355,20 @@ *piPos = iAdj; } return rc; } + +/* +** Return the value in pVal interpreted as utf-8 text. Except, if pVal +** contains a NULL value, return a pointer to a static string zero +** bytes in length instead of a NULL pointer. +*/ +static const char *valueToText(sqlite3_value *pVal){ + const char *zRet = (const char*)sqlite3_value_text(pVal); + return zRet ? zRet : ""; +} /* ** Implementation of snippet() function. */ static void fts5SnippetFunction( @@ -391,13 +401,13 @@ } nCol = pApi->xColumnCount(pFts); memset(&ctx, 0, sizeof(HighlightContext)); iCol = sqlite3_value_int(apVal[0]); - ctx.zOpen = (const char*)sqlite3_value_text(apVal[1]); - ctx.zClose = (const char*)sqlite3_value_text(apVal[2]); - zEllips = (const char*)sqlite3_value_text(apVal[3]); + ctx.zOpen = valueToText(apVal[1]); + ctx.zClose = valueToText(apVal[2]); + zEllips = valueToText(apVal[3]); nToken = sqlite3_value_int(apVal[4]); iBestCol = (iCol>=0 ? iCol : 0); nPhrase = pApi->xPhraseCount(pFts); aSeen = sqlite3_malloc(nPhrase); Index: ext/fts5/test/fts5af.test ================================================================== --- ext/fts5/test/fts5af.test +++ ext/fts5/test/fts5af.test @@ -172,9 +172,19 @@ ); } do_execsql_test 5.1 { SELECT snippet(p1, 0, '[', ']', '...', 6) FROM p1('x'); } {{[x] a a a a a...}} + +do_execsql_test 5.2 { + SELECT snippet(p1, 0, '[', ']', NULL, 6) FROM p1('x'); +} {{[x] a a a a a}} +do_execsql_test 5.3 { + SELECT snippet(p1, 0, NULL, ']', '...', 6) FROM p1('x'); +} {{x] a a a a a...}} +do_execsql_test 5.4 { + SELECT snippet(p1, 0, '[', NULL, '...', 6) FROM p1('x'); +} {{[x a a a a a...}} } ;# foreach_detail_mode finish_test