From 19e19a2f4291f1ef6d33eea4965bfe472638d095 Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@osmosoft.com>
Date: Tue, 8 May 2012 16:02:24 +0100
Subject: [PATCH] Added sort operator to filter syntax

---
 core/modules/commands/dump.js |  4 ++--
 core/modules/macros/list.js   |  2 +-
 core/modules/wiki.filters.js  | 32 +++++++++++++++++++++-----------
 core/modules/wiki.js          | 29 ++++++++++++++++++++++++++---
 4 files changed, 50 insertions(+), 17 deletions(-)

diff --git a/core/modules/commands/dump.js b/core/modules/commands/dump.js
index 48e57d251..2f989e691 100644
--- a/core/modules/commands/dump.js
+++ b/core/modules/commands/dump.js
@@ -50,7 +50,7 @@ Command.prototype.subcommands.tiddler = function() {
 };
 
 Command.prototype.subcommands.tiddlers = function() {
-	var tiddlers = this.commander.wiki.sortTiddlers();
+	var tiddlers = this.commander.wiki.getTiddlers();
 	this.output.write("Wiki contains these tiddlers:\n");
 	for(var t=0; t<tiddlers.length; t++) {
 		this.output.write(tiddlers[t] + "\n");
@@ -59,7 +59,7 @@ Command.prototype.subcommands.tiddlers = function() {
 };
 
 Command.prototype.subcommands.shadows = function() {
-	var tiddlers = this.commander.wiki.shadows.sortTiddlers();
+	var tiddlers = this.commander.wiki.shadows.getTiddlers();
 	this.output.write("Wiki contains these shadow tiddlers:\n");
 	for(var t=0; t<tiddlers.length; t++) {
 		this.output.write(tiddlers[t] + "\n");
diff --git a/core/modules/macros/list.js b/core/modules/macros/list.js
index a1b06c1f5..06a9bdbcf 100644
--- a/core/modules/macros/list.js
+++ b/core/modules/macros/list.js
@@ -12,7 +12,7 @@ module-type: macro
 
 var handlers = {
 	all: function(wiki) {
-		return wiki.sortTiddlers("title","excludeLists");
+		return wiki.getTiddlers("title","excludeLists");
 	},
 	missing: function(wiki) {
 		return wiki.getMissingTitles();
diff --git a/core/modules/wiki.filters.js b/core/modules/wiki.filters.js
index cb44ec1bb..5c9761149 100644
--- a/core/modules/wiki.filters.js
+++ b/core/modules/wiki.filters.js
@@ -69,7 +69,7 @@ exports.filterTiddlers = function(filterString) {
 };
 
 /*
-Compiling a filter gives a JavaScript function that is invoked as `filter(source)`, where `source` is a hashmap of source tiddler titles (the values don't matter, so it is possible to use a store or a changes object). It returns an array of tiddler titles that satisfy the filter
+Compiling a filter gives a JavaScript function that is invoked as `this.filter(source)`, where `source` is a hashmap of source tiddler titles (the values don't matter, so it is possible to use a store or a changes object). It returns an array of tiddler titles that satisfy the filter
 */
 exports.compileFilter = function(filterString) {
 	var filter = this.parseFilter(filterString),
@@ -96,9 +96,10 @@ exports.compileFilter = function(filterString) {
 		output.push(operationInfo.epilogue);
 	}
 	output.push(this.filterFragments.epilogue);
+console.log("Compiled filter to ",output.join("\n"));
 	try {
 		/*jslint evil: true */
-		fn = eval(output.join(""));
+		fn = eval(output.join("\n"));
 	} catch(ex) {
 		throw "Error in filter expression: " + ex;
 	}
@@ -106,21 +107,21 @@ exports.compileFilter = function(filterString) {
 };
 
 exports.filterFragments = {
-	prologue: "(function(source) {\nvar results = [], subResults;\n",
+	prologue: "(function(source) {\nvar results = [], subResults;",
 	epilogue: "return results;\n})",
 	operation: {
 		prefix: {
 			"": {
-				prologue: "subResults = [];\n",
-				epilogue: "$tw.utils.pushTop(results,subResults);\n"
+				prologue: "subResults = [];",
+				epilogue: "$tw.utils.pushTop(results,subResults);"
 			},
 			"+": {
-				prologue: "subResults = results.slice(0);\nresults.splice(0,results.length);\n",
-				epilogue: "$tw.utils.pushTop(results,subResults);\n"
+				prologue: "subResults = results.slice(0);\nresults.splice(0,results.length);",
+				epilogue: "$tw.utils.pushTop(results,subResults);"
 			},
 			"-": {
-				prologue: "subResults = [];\n",
-				epilogue: "$tw.utils.removeArrayEntries(results,subResults);\n"
+				prologue: "subResults = [];",
+				epilogue: "$tw.utils.removeArrayEntries(results,subResults);"
 			}
 		}
 	}
@@ -129,10 +130,10 @@ exports.filterFragments = {
 exports.operators = {
 	"title": {
 		selector: function(operator) {
-			return "if($tw.utils.hop(source,\"" + $tw.utils.stringify(operator.operand) + "\")) {$tw.utils.pushTop(subResults,\"" + $tw.utils.stringify(operator.operand) + "\");}\n";
+			return "if($tw.utils.hop(source,\"" + $tw.utils.stringify(operator.operand) + "\")) {$tw.utils.pushTop(subResults,\"" + $tw.utils.stringify(operator.operand) + "\");}";
 		},
 		filter: function(operator) {
-			return "if(subResults.indexOf(\"" + $tw.utils.stringify(operator.operand) + "\") !== -1) {subResults = [\"" + $tw.utils.stringify(operator.operand) + "\"];} else {subResults = [];}\n";
+			return "if(subResults.indexOf(\"" + $tw.utils.stringify(operator.operand) + "\") !== -1) {subResults = [\"" + $tw.utils.stringify(operator.operand) + "\"];} else {subResults = [];}";
 		}
 	},
 	"is": {
@@ -183,6 +184,15 @@ exports.operators = {
 			return "for(var r=subResults.length-1; r>=0; r--) {if(this.getTiddler(subResults[r]).fields[\"" + $tw.utils.stringify(operator.operand) + "\"] " + op + "== undefined) {subResults.splice(r,1);}}";
 		}
 	},
+	"sort": {
+		selector: function(operator) {
+			throw "Cannot use sort operator at the start of a sort operation";
+		},
+		filter: function(operator) {
+			var desc = operator.prefix === "!" ? "true" : "false";
+			return "this.sortTiddlers(subResults,\"" + $tw.utils.stringify(operator.operand) + "\"," + desc + ");"
+		}
+	},
 	"field": {
 		selector: function(operator) {
 			var op = operator.prefix === "!" ? "!" : "=";
diff --git a/core/modules/wiki.js b/core/modules/wiki.js
index 18ad10f2f..8d22c7aee 100644
--- a/core/modules/wiki.js
+++ b/core/modules/wiki.js
@@ -131,7 +131,7 @@ exports.serializeTiddler = function(title,type) {
 /*
 Return a sorted array of tiddler titles, optionally filtered by a tag 
 */
-exports.sortTiddlers = function(sortField,excludeTag) {
+exports.getTiddlers = function(sortField,excludeTag) {
 	sortField = sortField || "title";
 	var tiddlers = [], t, titles = [];
 	for(t in this.tiddlers) {
@@ -158,12 +158,35 @@ exports.sortTiddlers = function(sortField,excludeTag) {
 	return titles;
 };
 
+/*
+Sort an array of tiddler titles by a specified field
+	titles: array of titles (sorted in place)
+	sortField: name of field to sort by
+	isDescending: true if the sort should be descending
+*/
+exports.sortTiddlers = function(titles,sortField,isDescending) {
+	var self = this;
+	titles.sort(function(a,b) {
+		var aa = self.getTiddler(a).fields[sortField] || 0,
+			bb = self.getTiddler(b).fields[sortField] || 0;
+		if(aa < bb) {
+			return isDescending ? +1 : -1;
+		} else {
+			if(aa > bb) {
+				return isDescending ? -1 : +1;
+			} else {
+				return 0;
+			}
+		}
+	});
+};
+
 exports.forEachTiddler = function(/* [sortField,[excludeTag,]]callback */) {
 	var arg = 0,
 		sortField = arguments.length > 1 ? arguments[arg++] : null,
 		excludeTag = arguments.length > 2 ? arguments[arg++] : null,
 		callback = arguments[arg++],
-		titles = this.sortTiddlers(sortField,excludeTag),
+		titles = this.getTiddlers(sortField,excludeTag),
 		t, tiddler;
 	for(t=0; t<titles.length; t++) {
 		tiddler = this.tiddlers[titles[t]];
@@ -182,7 +205,7 @@ exports.getOrphanTitles = function() {
 };
 
 exports.getShadowTitles = function() {
-	return this.shadows ? this.shadows.sortTiddlers() : [];
+	return this.shadows ? this.shadows.getTiddlers() : [];
 };
 
 // Return the named cache object for a tiddler. If the cache doesn't exist then the initializer function is invoked to create it