Convert an assert() back into a conditional. The conditional was converted

into an assert() by check-in [6ae4ad6ebee4db88] (2009-05-28) because we were
unable to find a test case for it.  Yongheng's fuzzer just now
found that test case.

FossilOrigin-Name: 4d0b9109f7a5312d4e136395e08b11dad64d746bc106ad44d47675e5b1dcb4ef

manifest

@@ -1,5 +1,5 @@
-C When\san\sINSERT\sis\sreceiving\scontent\sfrom\sa\sSELECT,\srun\san\sOP_ReleaseReg\sopcode\nat\sthe\stop\sof\seach\siteration\sof\sthe\sloop\sin\sorder\sto\sprevent\sspurious\nOP_SCopy\smisuse\scomplaints.\s\sTicket\s[de4b04149b9fdeae]
-D 2019-12-28T01:52:46.568
+C Convert\san\sassert()\sback\sinto\sa\sconditional.\s\sThe\sconditional\swas\sconverted\ninto\san\sassert()\sby\scheck-in\s[6ae4ad6ebee4db88]\s(2009-05-28)\sbecause\swe\swere\nunable\sto\sfind\sa\stest\scase\sfor\sit.\s\sYongheng's\sfuzzer\sjust\snow\nfound\sthat\stest\scase.
+D 2019-12-28T02:40:49.716
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -480,7 +480,7 @@ F src/date.c e1d8ac7102f3f283e63e13867acb0efa33861cf34f0faf4cdbaf9fa7a1eb7041
 F src/dbpage.c 135eb3b5e74f9ef74bde5cec2571192c90c86984fa534c88bf4a055076fa19b7
 F src/dbstat.c 6c407e549406c10fde9ac3987f6d734459205239ad370369bc5fcd683084a4fa
 F src/delete.c a5c59b9c0251cf7682bc52af0d64f09b1aefc6781a63592c8f1136f7b73c66e4
-F src/expr.c 188a8c039c95a0b4adb6c9dcde7252810c90e5145333634b924cbe348b187df8
+F src/expr.c de4fa05000145cbb6ff29b106e2c7dded5fe3d7882c518b2bc6f63c27891a645
 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007
 F src/fkey.c 92a248ec0fa4ed8ab60c98d9b188ce173aaf218f32e7737ba77deb2a684f9847
 F src/func.c ed33e38cd642058182a31a3f518f2e34f4bbe53aa483335705c153c4d3e50b12
@@ -1853,7 +1853,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 4cc12c18860bc4801a407cf45e88e23d3d40391f01a461fbac2cac5f102100e1
-R 27f90cf00e11bc62225fb137834fb1e7
+P 6afadd3b3a40b0ef29fd14fb24c2a4b9479483e5f8b9125ce02d8daae662207f
+R 4b3499031b2124e5f56fb355fbad44a0
 U drh
-Z 9a630124c807dd4207b2667c21867988
+Z cf16da0339b8c2d85e2898cd693cab42

manifest.uuid

@@ -1 +1 @@
-6afadd3b3a40b0ef29fd14fb24c2a4b9479483e5f8b9125ce02d8daae662207f
+4d0b9109f7a5312d4e136395e08b11dad64d746bc106ad44d47675e5b1dcb4ef

src/expr.c

@@ -2292,7 +2292,7 @@ static Select *isCandidateForInOpt(Expr *pX){
     testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate );
     return 0; /* No DISTINCT keyword and no aggregate functions */
   }
-  assert( p->pGroupBy==0 );              /* Has no GROUP BY clause */
+  if( p->pGroupBy ) return 0;            /* Has no GROUP BY clause */
   if( p->pLimit ) return 0;              /* Has no LIMIT clause */
   if( p->pWhere ) return 0;              /* Has no WHERE clause */
   pSrc = p->pSrc;