hgweb: fix unstoppable loading of graph when no more results

When a user reaches the end of repo history with graph view, it (unsuccessfully)
tried to load more entries. This patch disables further loading attempts.

mercurial/templates/static/mercurial.js

@@ -1,439 +1,442 b''
 // mercurial.js - JavaScript utility functions
 //
 // Rendering of branch DAGs on the client side
 // Display of elapsed time
 // Show or hide diffstat
 //
 // Copyright 2008 Dirkjan Ochtman <dirkjan AT ochtman DOT nl>
 // Copyright 2006 Alexander Schremmer <alex AT alexanderweb DOT de>
 //
 // derived from code written by Scott James Remnant <[e-mail]>
 // Copyright 2005 Canonical Ltd.
 //
 // This software may be used and distributed according to the terms
 // of the GNU General Public License, incorporated herein by reference.
 
 var colors = [
 	[ 1.0, 0.0, 0.0 ],
 	[ 1.0, 1.0, 0.0 ],
 	[ 0.0, 1.0, 0.0 ],
 	[ 0.0, 1.0, 1.0 ],
 	[ 0.0, 0.0, 1.0 ],
 	[ 1.0, 0.0, 1.0 ]
 ];
 
 function Graph() {
 
 	this.canvas = document.getElementById('graph');
 	if (window.G_vmlCanvasManager) this.canvas = window.G_vmlCanvasManager.initElement(this.canvas);
 	this.ctx = this.canvas.getContext('2d');
 	this.ctx.strokeStyle = 'rgb(0, 0, 0)';
 	this.ctx.fillStyle = 'rgb(0, 0, 0)';
 	this.cur = [0, 0];
 	this.line_width = 3;
 	this.bg = [0, 4];
 	this.cell = [2, 0];
 	this.columns = 0;
 	this.revlink = '';
 
 	this.reset = function() {
 		this.bg = [0, 4];
 		this.cell = [2, 0];
 		this.columns = 0;
 		document.getElementById('nodebgs').innerHTML = '';
 		document.getElementById('graphnodes').innerHTML = '';
 	}
 
 	this.scale = function(height) {
 		this.bg_height = height;
 		this.box_size = Math.floor(this.bg_height / 1.2);
 		this.cell_height = this.box_size;
 	}
 
 	function colorPart(num) {
 		num *= 255
 		num = num < 0 ? 0 : num;
 		num = num > 255 ? 255 : num;
 		var digits = Math.round(num).toString(16);
 		if (num < 16) {
 			return '0' + digits;
 		} else {
 			return digits;
 		}
 	}
 
 	this.setColor = function(color, bg, fg) {
 
 		// Set the colour.
 		//
 		// If color is a string, expect an hexadecimal RGB
 		// value and apply it unchanged. If color is a number,
 		// pick a distinct colour based on an internal wheel;
 		// the bg parameter provides the value that should be
 		// assigned to the 'zero' colours and the fg parameter
 		// provides the multiplier that should be applied to
 		// the foreground colours.
 		var s;
 		if(typeof color == "string") {
 			s = "#" + color;
 		} else { //typeof color == "number"
 			color %= colors.length;
 			var red = (colors[color][0] * fg) || bg;
 			var green = (colors[color][1] * fg) || bg;
 			var blue = (colors[color][2] * fg) || bg;
 			red = Math.round(red * 255);
 			green = Math.round(green * 255);
 			blue = Math.round(blue * 255);
 			s = 'rgb(' + red + ', ' + green + ', ' + blue + ')';
 		}
 		this.ctx.strokeStyle = s;
 		this.ctx.fillStyle = s;
 		return s;
 
 	}
 
 	this.edge = function(x0, y0, x1, y1, color, width) {
 
 		this.setColor(color, 0.0, 0.65);
 		if(width >= 0)
 			 this.ctx.lineWidth = width;
 		this.ctx.beginPath();
 		this.ctx.moveTo(x0, y0);
 		this.ctx.lineTo(x1, y1);
 		this.ctx.stroke();
 
 	}
 
 	this.render = function(data) {
 
 		var backgrounds = '';
 		var nodedata = '';
 
 		for (var i in data) {
 
 			var parity = i % 2;
 			this.cell[1] += this.bg_height;
 			this.bg[1] += this.bg_height;
 
 			var cur = data[i];
 			var node = cur[1];
 			var edges = cur[2];
 			var fold = false;
 
 			var prevWidth = this.ctx.lineWidth;
 			for (var j in edges) {
 
 				line = edges[j];
 				start = line[0];
 				end = line[1];
 				color = line[2];
 				var width = line[3];
 				if(width < 0)
 					 width = prevWidth;
 				var branchcolor = line[4];
 				if(branchcolor)
 					color = branchcolor;
 
 				if (end > this.columns || start > this.columns) {
 					this.columns += 1;
 				}
 
 				if (start == this.columns && start > end) {
 					var fold = true;
 				}
 
 				x0 = this.cell[0] + this.box_size * start + this.box_size / 2;
 				y0 = this.bg[1] - this.bg_height / 2;
 				x1 = this.cell[0] + this.box_size * end + this.box_size / 2;
 				y1 = this.bg[1] + this.bg_height / 2;
 
 				this.edge(x0, y0, x1, y1, color, width);
 
 			}
 			this.ctx.lineWidth = prevWidth;
 
 			// Draw the revision node in the right column
 
 			column = node[0]
 			color = node[1]
 
 			radius = this.box_size / 8;
 			x = this.cell[0] + this.box_size * column + this.box_size / 2;
 			y = this.bg[1] - this.bg_height / 2;
 			var add = this.vertex(x, y, color, parity, cur);
 			backgrounds += add[0];
 			nodedata += add[1];
 
 			if (fold) this.columns -= 1;
 
 		}
 
 		document.getElementById('nodebgs').innerHTML += backgrounds;
 		document.getElementById('graphnodes').innerHTML += nodedata;
 
 	}
 
 }
 
 
 function process_dates(parentSelector){
 
 	// derived from code from mercurial/templatefilter.py
 
 	var scales = {
 		'year':  365 * 24 * 60 * 60,
 		'month':  30 * 24 * 60 * 60,
 		'week':    7 * 24 * 60 * 60,
 		'day':    24 * 60 * 60,
 		'hour':   60 * 60,
 		'minute': 60,
 		'second': 1
 	};
 
 	function format(count, string){
 		var ret = count + ' ' + string;
 		if (count > 1){
 			ret = ret + 's';
 		}
  		return ret;
  	}
 
 	function shortdate(date){
 		var ret = date.getFullYear() + '-';
 		// getMonth() gives a 0-11 result
 		var month = date.getMonth() + 1;
 		if (month <= 9){
 			ret += '0' + month;
 		} else {
 			ret += month;
 		}
 		ret += '-';
 		var day = date.getDate();
 		if (day <= 9){
 			ret += '0' + day;
 		} else {
 			ret += day;
 		}
 		return ret;
 	}
 
  	function age(datestr){
  		var now = new Date();
  		var once = new Date(datestr);
 		if (isNaN(once.getTime())){
 			// parsing error
 			return datestr;
 		}
 
 		var delta = Math.floor((now.getTime() - once.getTime()) / 1000);
 
 		var future = false;
 		if (delta < 0){
 			future = true;
 			delta = -delta;
 			if (delta > (30 * scales.year)){
 				return "in the distant future";
 			}
 		}
 
 		if (delta > (2 * scales.year)){
 			return shortdate(once);
 		}
 
 		for (unit in scales){
 			var s = scales[unit];
 			var n = Math.floor(delta / s);
 			if ((n >= 2) || (s == 1)){
 				if (future){
 					return format(n, unit) + ' from now';
 				} else {
 					return format(n, unit) + ' ago';
 				}
 			}
 		}
 	}
 
 	var nodes = document.querySelectorAll((parentSelector || '') + ' .age');
 	var dateclass = new RegExp('\\bdate\\b');
 	for (var i=0; i<nodes.length; ++i){
 		var node = nodes[i];
 		var classes = node.className;
 		var agevalue = age(node.textContent);
 		if (dateclass.test(classes)){
 			// We want both: date + (age)
 			node.textContent += ' ('+agevalue+')';
 		} else {
 			node.title = node.textContent;
 			node.textContent = agevalue;
 		}
 	}
 }
 
 function toggleDiffstat() {
     var curdetails = document.getElementById('diffstatdetails').style.display;
     var curexpand = curdetails == 'none' ? 'inline' : 'none';
     document.getElementById('diffstatdetails').style.display = curexpand;
     document.getElementById('diffstatexpand').style.display = curdetails;
 }
 
 function toggleLinewrap() {
     function getLinewrap() {
         var nodes = document.getElementsByClassName('sourcelines');
         // if there are no such nodes, error is thrown here
         return nodes[0].classList.contains('wrap');
     }
 
     function setLinewrap(enable) {
         var nodes = document.getElementsByClassName('sourcelines');
         for (var i = 0; i < nodes.length; i++) {
             if (enable) {
                 nodes[i].classList.add('wrap');
             } else {
                 nodes[i].classList.remove('wrap');
             }
         }
 
         var links = document.getElementsByClassName('linewraplink');
         for (var i = 0; i < links.length; i++) {
             links[i].innerHTML = enable ? 'on' : 'off';
         }
     }
 
     setLinewrap(!getLinewrap());
 }
 
 function format(str, replacements) {
     return str.replace(/%(\w+)%/g, function(match, p1) {
         return String(replacements[p1]);
     });
 }
 
 function makeRequest(url, method, onstart, onsuccess, onerror, oncomplete) {
     xfr = new XMLHttpRequest();
     xfr.onreadystatechange = function() {
         if (xfr.readyState === 4) {
             try {
                 if (xfr.status === 200) {
                     onsuccess(xfr.responseText);
                 } else {
                     throw 'server error';
                 }
             } catch (e) {
                 onerror(e);
             } finally {
                 oncomplete();
             }
         }
     };
 
     xfr.open(method, url);
     xfr.send();
     onstart();
     return xfr;
 }
 
 function removeByClassName(className) {
     var nodes = document.getElementsByClassName(className);
     while (nodes.length) {
         nodes[0].parentNode.removeChild(nodes[0]);
     }
 }
 
 function docFromHTML(html) {
     var doc = document.implementation.createHTMLDocument('');
     doc.documentElement.innerHTML = html;
     return doc;
 }
 
 function appendFormatHTML(element, formatStr, replacements) {
     element.insertAdjacentHTML('beforeend', format(formatStr, replacements));
 }
 
 function ajaxScrollInit(urlFormat,
                         nextPageVar,
                         nextPageVarGet,
                         containerSelector,
                         messageFormat,
                         mode) {
     updateInitiated = false;
     container = document.querySelector(containerSelector);
 
     function scrollHandler() {
         if (updateInitiated) {
             return;
         }
 
         var scrollHeight = document.documentElement.scrollHeight;
         var clientHeight = document.documentElement.clientHeight;
         var scrollTop = document.body.scrollTop
             || document.documentElement.scrollTop;
 
         if (scrollHeight - (scrollTop + clientHeight) < 50) {
             updateInitiated = true;
             removeByClassName('scroll-loading-error');
             container.lastElementChild.classList.add('scroll-separator');
 
             if (!nextPageVar) {
                 var message = {
                     class: 'scroll-loading-info',
                     text: 'No more entries'
                 };
                 appendFormatHTML(container, messageFormat, message);
                 return;
             }
 
             makeRequest(
                 format(urlFormat, {next: nextPageVar}),
                 'GET',
                 function onstart() {
                     var message = {
                         class: 'scroll-loading',
                         text: 'Loading...'
                     };
                     appendFormatHTML(container, messageFormat, message);
                 },
                 function onsuccess(htmlText) {
-                    nextPageVar = nextPageVarGet(htmlText, nextPageVar);
-
                     if (mode == 'graph') {
                         var addHeight = htmlText.match(/^<canvas id="graph".*height="(\d+)"><\/canvas>$/m)[1];
                         addHeight = parseInt(addHeight);
                         graph.canvas.height = addHeight;
 
                         var dataStr = htmlText.match(/^\s*var data = (.*);$/m)[1];
                         var data = JSON.parse(dataStr)
+                        if (data.length < nextPageVar) {
+                            nextPageVar = undefined;
+                        }
                         graph.reset();
                         graph.render(data);
                     } else {
                         var doc = docFromHTML(htmlText);
                         var nodes = doc.querySelector(containerSelector).children;
                         var curClass = 'c' + Date.now();
                         while (nodes.length) {
                             var node = nodes[0];
                             node = document.adoptNode(node);
                             node.classList.add(curClass);
                             container.appendChild(node);
                         }
                         process_dates('.' + curClass);
                     }
+
+                    nextPageVar = nextPageVarGet(htmlText, nextPageVar);
                 },
                 function onerror(errorText) {
                     var message = {
                         class: 'scroll-loading-error',
                         text: 'Error: ' + errorText
                     };
                     appendFormatHTML(container, messageFormat, message);
                 },
                 function oncomplete() {
                     removeByClassName('scroll-loading');
                     updateInitiated = false;
                     scrollHandler();
                 }
             );
         }
     }
 
     window.addEventListener('scroll', scrollHandler);
     window.addEventListener('resize', scrollHandler);
     scrollHandler();
 }