Enhance the TreeView mechanism so that it shows the window function
data structures as part of the abstract syntax tree.

FossilOrigin-Name: a2c0e1bec0d8a6f982572c4c5a8166319b8db0fe586057f7900f0ab72af6554e
diff --git a/src/treeview.c b/src/treeview.c
index 970d85e..1ece76f 100644
--- a/src/treeview.c
+++ b/src/treeview.c
@@ -165,8 +165,23 @@
       if( p->pHaving ) n++;
       if( p->pOrderBy ) n++;
       if( p->pLimit ) n++;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+      if( p->pWin ) n++;
+      if( p->pWinDefn ) n++;
+#endif
     }
     sqlite3TreeViewExprList(pView, p->pEList, (n--)>0, "result-set");
+#ifndef SQLITE_OMIT_WINDOWFUNC
+    if( p->pWin ){
+      Window *pX;
+      pView = sqlite3TreeViewPush(pView, (n--)>0);
+      sqlite3TreeViewLine(pView, "window-functions");
+      for(pX=p->pWin; pX; pX=pX->pNextWin){
+        sqlite3TreeViewWinFunc(pView, pX, pX->pNextWin!=0);
+      }
+      sqlite3TreeViewPop(pView);
+    }
+#endif
     if( p->pSrc && p->pSrc->nSrc ){
       int i;
       pView = sqlite3TreeViewPush(pView, (n--)>0);
@@ -216,6 +231,16 @@
       sqlite3TreeViewExpr(pView, p->pHaving, 0);
       sqlite3TreeViewPop(pView);
     }
+#ifndef SQLITE_OMIT_WINDOWFUNC
+    if( p->pWinDefn ){
+      Window *pX;
+      sqlite3TreeViewItem(pView, "WINDOW", (n--)>0);
+      for(pX=p->pWinDefn; pX; pX=pX->pNextWin){
+        sqlite3TreeViewWindow(pView, pX, pX->pNextWin!=0);
+      }
+      sqlite3TreeViewPop(pView);
+    }
+#endif
     if( p->pOrderBy ){
       sqlite3TreeViewExprList(pView, p->pOrderBy, (n--)>0, "ORDERBY");
     }
@@ -243,6 +268,83 @@
   sqlite3TreeViewPop(pView);
 }
 
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a description of starting or stopping bounds
+*/
+void sqlite3TreeViewBound(
+  TreeView *pView,        /* View context */
+  u8 eBound,              /* UNBOUNDED, CURRENT, PRECEDING, FOLLOWING */
+  Expr *pExpr,            /* Value for PRECEDING or FOLLOWING */
+  u8 moreToFollow         /* True if more to follow */
+){
+  switch( eBound ){
+    case TK_UNBOUNDED: {
+      sqlite3TreeViewItem(pView, "UNBOUNDED", moreToFollow);
+      sqlite3TreeViewPop(pView);
+      break;
+    }
+    case TK_CURRENT: {
+      sqlite3TreeViewItem(pView, "CURRENT", moreToFollow);
+      sqlite3TreeViewPop(pView);
+      break;
+    }
+    case TK_PRECEDING: {
+      sqlite3TreeViewItem(pView, "PRECEDING", moreToFollow);
+      sqlite3TreeViewExpr(pView, pExpr, 0);
+      sqlite3TreeViewPop(pView);
+      break;
+    }
+    case TK_FOLLOWING: {
+      sqlite3TreeViewItem(pView, "FOLLOWING", moreToFollow);
+      sqlite3TreeViewExpr(pView, pExpr, 0);
+      sqlite3TreeViewPop(pView);
+      break;
+    }
+  }
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a human-readable explanation for a Window object
+*/
+void sqlite3TreeViewWindow(TreeView *pView, const Window *pWin, u8 more){
+  pView = sqlite3TreeViewPush(pView, more);
+  if( pWin->zName ){
+    sqlite3TreeViewLine(pView, "OVER %s", pWin->zName);
+  }else{
+    sqlite3TreeViewLine(pView, "OVER");
+  }
+  if( pWin->pPartition ){
+    sqlite3TreeViewExprList(pView, pWin->pPartition, 1, "PARTITION-BY");
+  }
+  if( pWin->pOrderBy ){
+    sqlite3TreeViewExprList(pView, pWin->pOrderBy, 1, "ORDER-BY");
+  }
+  if( pWin->eType ){
+    sqlite3TreeViewItem(pView, pWin->eType==TK_RANGE ? "RANGE" : "ROWS", 0);
+    sqlite3TreeViewBound(pView, pWin->eStart, pWin->pStart, 1);
+    sqlite3TreeViewBound(pView, pWin->eEnd, pWin->pEnd, 0);
+    sqlite3TreeViewPop(pView);
+  }
+  sqlite3TreeViewPop(pView);
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** Generate a human-readable explanation for a Window Function object
+*/
+void sqlite3TreeViewWinFunc(TreeView *pView, const Window *pWin, u8 more){
+  pView = sqlite3TreeViewPush(pView, more);
+  sqlite3TreeViewLine(pView, "WINFUNC %s(%d)",
+                       pWin->pFunc->zName, pWin->pFunc->nArg);
+  sqlite3TreeViewWindow(pView, pWin, 0);
+  sqlite3TreeViewPop(pView);
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
+
 /*
 ** Generate a human-readable explanation of an expression tree.
 */
@@ -393,10 +495,17 @@
     case TK_AGG_FUNCTION:
     case TK_FUNCTION: {
       ExprList *pFarg;       /* List of function arguments */
+      Window *pWin;
       if( ExprHasProperty(pExpr, EP_TokenOnly) ){
         pFarg = 0;
+        pWin = 0;
       }else{
         pFarg = pExpr->x.pList;
+#ifndef SQLITE_OMIT_WINDOWFUNC
+        pWin = pExpr->pWin;
+#else
+        pWin = 0;
+#endif 
       }
       if( pExpr->op==TK_AGG_FUNCTION ){
         sqlite3TreeViewLine(pView, "AGG_FUNCTION%d %Q",
@@ -405,8 +514,13 @@
         sqlite3TreeViewLine(pView, "FUNCTION %Q", pExpr->u.zToken);
       }
       if( pFarg ){
-        sqlite3TreeViewExprList(pView, pFarg, 0, 0);
+        sqlite3TreeViewExprList(pView, pFarg, pWin!=0, 0);
       }
+#ifndef SQLITe_OMIT_WINDOWFUNC
+      if( pWin ){
+        sqlite3TreeViewWindow(pView, pWin, 0);
+      }
+#endif
       break;
     }
 #ifndef SQLITE_OMIT_SUBQUERY