Replace some unreachable branches from the JSON1 extension with assert().

FossilOrigin-Name: 145cd13e3c5a42a717807bcc13c0f7212f38bff8

ext/misc/json1.c

@@ -595,12 +595,13 @@ static void jsonReturn(
             c = z[++i];
             if( c=='u' ){
               u32 v = 0, k;
-              for(k=0; k<4 && i<n-2; i++, k++){
+              for(k=0; k<4; i++, k++){
+                assert( i<n-2 );
                 c = z[i+1];
-                if( c>='0' && c<='9' ) v = v*16 + c - '0';
-                else if( c>='A' && c<='F' ) v = v*16 + c - 'A' + 10;
-                else if( c>='a' && c<='f' ) v = v*16 + c - 'a' + 10;
-                else break;
+                assert( safe_isxdigit(c) );
+                if( c<='9' ) v = v*16 + c - '0';
+                else if( c<='F' ) v = v*16 + c - 'A' + 10;
+                else v = v*16 + c - 'a' + 10;
               }
               if( v==0 ) break;
               if( v<=0x7f ){

manifest

@@ -1,5 +1,5 @@
-C Fix\sthe\sJSON1\sextension\sso\sthat\sthe\sJSON\svalidator\scorrectly\srejects\smalformed\nbackslash\sescapes\swithin\sstring\sliterals.
-D 2016-11-07T13:37:28.861
+C Replace\ssome\sunreachable\sbranches\sfrom\sthe\sJSON1\sextension\swith\sassert().
+D 2016-11-07T15:15:42.501
 F Makefile.in 6fd48ffcf7c2deea7499062d1f3747f986c19678
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc e0217f2d35a0448abbe4b066132ae20136e8b408
@@ -213,7 +213,7 @@ F ext/misc/eval.c f971962e92ebb8b0a4e6b62949463ee454d88fa2
 F ext/misc/fileio.c d4171c815d6543a9edef8308aab2951413cd8d0f
 F ext/misc/fuzzer.c 7c64b8197bb77b7d64eff7cac7848870235d4c25
 F ext/misc/ieee754.c f190d0cc5182529acb15babd177781be1ac1718c
-F ext/misc/json1.c 813a2ff17b3e951a4b875ef79b5f4a0543cb0a2d
+F ext/misc/json1.c b8aa1219d25df9c135e067844f515cbaa452395d
 F ext/misc/memvfs.c e5225bc22e79dde6b28380f3a068ddf600683a33
 F ext/misc/nextchar.c 35c8b8baacb96d92abbb34a83a997b797075b342
 F ext/misc/percentile.c 92699c8cd7d517ff610e6037e56506f8904dae2e
@@ -1530,7 +1530,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P b86b79c442a58d10aa005ba4f34095375a88d242
-R 7a809bd65e85c52e8075f2c4e33138f7
+P 7a63539169a384960e30a63e0c8e9b0f07fa431e
+R 301a8516f843000230cab1da4034b3ce
 U drh
-Z 3735bc72c61a220065b296aebe8a3b9c
+Z 60f1523be64826a7825849d4d0d5f745

manifest.uuid

@@ -1 +1 @@
-7a63539169a384960e30a63e0c8e9b0f07fa431e
+145cd13e3c5a42a717807bcc13c0f7212f38bff8