From 3afaa9de9aaae7654c1d03ddc22ee97724cbb159 Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@jermolene.com>
Date: Wed, 31 Jul 2019 21:36:12 +0100
Subject: [PATCH] Add support for anchored searches

---
 core/modules/filters/search.js               |  1 +
 core/modules/wiki.js                         | 10 ++++++----
 editions/test/tiddlers/tests/test-filters.js |  1 +
 editions/tw5.com/tiddlers/filters/search.tid |  3 ++-
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/core/modules/filters/search.js b/core/modules/filters/search.js
index 1e59deb63..adcb076a0 100644
--- a/core/modules/filters/search.js
+++ b/core/modules/filters/search.js
@@ -43,6 +43,7 @@ exports.search = function(source,operator,options) {
 			caseSensitive: hasFlag("casesensitive"),
 			literal: hasFlag("literal"),
 			whitespace: hasFlag("whitespace"),
+			anchored: hasFlag("anchored"),
 			regexp: hasFlag("regexp"),
 			words: hasFlag("words")
 		});
diff --git a/core/modules/wiki.js b/core/modules/wiki.js
index 4d1f938e7..3e5687638 100755
--- a/core/modules/wiki.js
+++ b/core/modules/wiki.js
@@ -1065,6 +1065,7 @@ Options available:
 	invert: If true returns tiddlers that do not contain the specified string
 	caseSensitive: If true forces a case sensitive search
 	field: If specified, restricts the search to the specified field, or an array of field names
+	anchored: If true, forces all but regexp searches to be anchored to the start of text
 	excludeField: If true, the field options are inverted to specify the fields that are not to be searched
 	The search mode is determined by the first of these boolean flags to be true
 		literal: searches for literal string
@@ -1079,12 +1080,13 @@ exports.search = function(text,options) {
 		invert = !!options.invert;
 	// Convert the search string into a regexp for each term
 	var terms, searchTermsRegExps,
-		flags = options.caseSensitive ? "" : "i";
+		flags = options.caseSensitive ? "" : "i",
+		anchor = options.anchored ? "^" : "";
 	if(options.literal) {
 		if(text.length === 0) {
 			searchTermsRegExps = null;
 		} else {
-			searchTermsRegExps = [new RegExp("(" + $tw.utils.escapeRegExp(text) + ")",flags)];
+			searchTermsRegExps = [new RegExp("(" + anchor + $tw.utils.escapeRegExp(text) + ")",flags)];
 		}
 	} else if(options.whitespace) {
 		terms = [];
@@ -1093,7 +1095,7 @@ exports.search = function(text,options) {
 				terms.push($tw.utils.escapeRegExp(term));
 			}
 		});
-		searchTermsRegExps = [new RegExp("(" + terms.join("\\s+") + ")",flags)];
+		searchTermsRegExps = [new RegExp("(" + anchor + terms.join("\\s+") + ")",flags)];
 	} else if(options.regexp) {
 		try {
 			searchTermsRegExps = [new RegExp("(" + text + ")",flags)];			
@@ -1108,7 +1110,7 @@ exports.search = function(text,options) {
 		} else {
 			searchTermsRegExps = [];
 			for(t=0; t<terms.length; t++) {
-				searchTermsRegExps.push(new RegExp("(" + $tw.utils.escapeRegExp(terms[t]) + ")",flags));
+				searchTermsRegExps.push(new RegExp("(" + anchor + $tw.utils.escapeRegExp(terms[t]) + ")",flags));
 			}
 		}
 	}
diff --git a/editions/test/tiddlers/tests/test-filters.js b/editions/test/tiddlers/tests/test-filters.js
index ae6f66de7..ab544c40f 100644
--- a/editions/test/tiddlers/tests/test-filters.js
+++ b/editions/test/tiddlers/tests/test-filters.js
@@ -313,6 +313,7 @@ function runTests(wiki) {
 		expect(wiki.filterTiddlers("[search:modifier:regexp[(d|bl)o(ggs|e)]sort[title]]").join(",")).toBe("$:/TiddlerTwo,a fourth tiddler,one,Tiddler Three,TiddlerOne");
 		expect(wiki.filterTiddlers("[search:-modifier,authors:[g]sort[title]]").join(",")).toBe("$:/ShadowPlugin,Tiddler Three");
 		expect(wiki.filterTiddlers("[search:*:[g]sort[title]]").join(",")).toBe("$:/ShadowPlugin,Tiddler Three,TiddlerOne");
+		expect(wiki.filterTiddlers("[search:text:anchored[the]]").join(",")).toBe("TiddlerOne,$:/TiddlerTwo,Tiddler Three,a fourth tiddler");
 	});
 
 	it("should yield search results that have search tokens spread across different fields", function() {
diff --git a/editions/tw5.com/tiddlers/filters/search.tid b/editions/tw5.com/tiddlers/filters/search.tid
index 9da7f8189..3aba89bf1 100644
--- a/editions/tw5.com/tiddlers/filters/search.tid
+++ b/editions/tw5.com/tiddlers/filters/search.tid
@@ -1,5 +1,5 @@
 created: 20140410103123179
-modified: 20181025082022690
+modified: 20190731212738712
 tags: [[Filter Operators]] [[Common Operators]] [[Field Operators]] [[Negatable Operators]]
 title: search Operator
 type: text/vnd.tiddlywiki
@@ -40,5 +40,6 @@ The available flags are:
 ** ''regexp'': treats the search string as a regular expression. Note that the ''regexp'' option obviates the need for the older <<.olink regexp>> operator.
 ** ''words'': (the default) treats the search string as a list of tokens separated by whitespace, and matches if all of the tokens appear in the string (regardless of ordering and whether there is other text in between)
 * ''casesensitive'': if present, this flag forces a case-sensitive match, where upper and lower case letters are considered different. By default, upper and lower case letters are considered identical for matching purposes.
+* ''anchored'': <<.from-version "5.1.20">> anchors the search to the start of the string (applies to ''whitespace'', ''literal'' and ''words'' modes)
 
 <<.operator-examples "search">>