Index: src/test_vdbecov.c
==================================================================
--- src/test_vdbecov.c
+++ src/test_vdbecov.c
@@ -34,15 +34,21 @@
   if( iSrc<sizeof(aBranchArray) ){
     aBranchArray[iSrc] |= iBranch;
   }
 }
 
-static void appendToList(Tcl_Obj *pList, int iLine, int iPath){
+static void appendToList(
+  Tcl_Obj *pList, 
+  int iLine, 
+  int iPath, 
+  const char *zNever
+){
   Tcl_Obj *pNew = Tcl_NewObj();
   Tcl_IncrRefCount(pNew);
   Tcl_ListObjAppendElement(0, pNew, Tcl_NewIntObj(iLine));
   Tcl_ListObjAppendElement(0, pNew, Tcl_NewIntObj(iPath));
+  Tcl_ListObjAppendElement(0, pNew, Tcl_NewStringObj(zNever, -1));
   Tcl_ListObjAppendElement(0, pList, pNew);
   Tcl_DecrRefCount(pNew);
 }
 
 
@@ -74,14 +80,21 @@
       int i;
       Tcl_Obj *pRes = Tcl_NewObj();
       Tcl_IncrRefCount(pRes);
       for(i=0; i<sizeof(aBranchArray); i++){
         u8 b = aBranchArray[i];
+        int bFlag = ((b >> 4)==4);
         if( b ){
-          if( (b & 0x01)==0 ) appendToList(pRes, i, 0);
-          if( (b & 0x02)==0 ) appendToList(pRes, i, 1);
-          if( (b & 0x04)==0 ) appendToList(pRes, i, 2);
+          if( (b & 0x01)==0 ){
+            appendToList(pRes, i, 0, bFlag ? "less than" : "falls through");
+          }
+          if( (b & 0x02)==0 ){
+            appendToList(pRes, i, 1, bFlag ? "equal" : "taken");
+          }
+          if( (b & 0x04)==0 ){
+            appendToList(pRes, i, 2, bFlag ? "greater-than" : "NULL");
+          }
         }
       }
       Tcl_SetObjResult(interp, pRes);
       Tcl_DecrRefCount(pRes);
       break;

Index: test/tester.tcl
==================================================================
--- test/tester.tcl
+++ test/tester.tcl
@@ -1328,21 +1328,21 @@
     }
     close $fd
   }
   set fd [open vdbe_coverage.txt w]
   foreach miss [vdbe_coverage report] {
-    foreach {line branch} $miss {}
+    foreach {line branch never} $miss {}
     set nextfile ""
     while {[llength $lSrc]>0 && [lindex $lSrc 0 0] < $line} {
       set nextfile [lindex $lSrc 0 1]
       set lSrc [lrange $lSrc 1 end]
     }
     if {$nextfile != ""} {
       puts $fd ""
       puts $fd "### $nextfile ###"
     }
-    puts $fd "Vdbe branch $line: path $branch never taken"
+    puts $fd "Vdbe branch $line: never $never (path $branch)"
   }
   close $fd
 }
 
 # Display memory statistics for analysis and debugging purposes.

Index: test/window1.test
==================================================================
--- test/window1.test
+++ test/window1.test
@@ -1065,10 +1065,23 @@
   SELECT c, c IN ( 
     SELECT row_number() OVER () FROM ( SELECT 1 FROM t1 WHERE x=c )
   ) FROM t2
 } {1 1  2 0  3 1  4 0}
 
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test 27.0 {
+  CREATE TABLE t1(x);
+  INSERT INTO t1 VALUES(NULL), (1), (2), (3), (4), (5);
+}
+do_execsql_test 27.1 {
+  SELECT min(x) FROM t1;
+} {1}
+do_execsql_test 27.2 {
+  SELECT min(x) OVER win FROM t1
+  WINDOW win AS (ORDER BY rowid ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING)
+} {1 1 1 2 3 4}
 
 
 finish_test