From d7a6816307f4fd47df29cb8e0343ea39c079a2b0 Mon Sep 17 00:00:00 2001
From: Jermolene <jeremy@jermolene.com>
Date: Sun, 29 Oct 2017 15:53:53 +0000
Subject: [PATCH] Add jsonstringify operator

---
 core/modules/filters/encodings.js             |  8 ++++++++
 core/modules/utils/utils.js                   | 19 ++++++++++++++++++-
 .../stringify_Operator_(Examples).tid         |  4 ++--
 .../jsonstringify Operator (Examples).tid     |  7 +++++++
 .../tiddlers/jsonstringify Operator.tid       | 14 ++++++++++++++
 5 files changed, 49 insertions(+), 3 deletions(-)
 create mode 100644 editions/tw5.com/tiddlers/jsonstringify Operator (Examples).tid
 create mode 100644 editions/tw5.com/tiddlers/jsonstringify Operator.tid

diff --git a/core/modules/filters/encodings.js b/core/modules/filters/encodings.js
index 24c44aaa3..b55911cdd 100644
--- a/core/modules/filters/encodings.js
+++ b/core/modules/filters/encodings.js
@@ -72,6 +72,14 @@ exports.stringify = function(source,operator,options) {
 	return results;
 };
 
+exports.jsonstringify = function(source,operator,options) {
+	var results = [];
+	source(function(tiddler,title) {
+		results.push($tw.utils.jsonStringify(title));
+	});
+	return results;
+};
+
 exports.escaperegexp = function(source,operator,options) {
 	var results = [];
 	source(function(tiddler,title) {
diff --git a/core/modules/utils/utils.js b/core/modules/utils/utils.js
index c80b6543d..a52f0cbf3 100644
--- a/core/modules/utils/utils.js
+++ b/core/modules/utils/utils.js
@@ -543,7 +543,24 @@ exports.stringify = function(s) {
 		.replace(/'/g, "\\'")              // single quote character
 		.replace(/\r/g, '\\r')             // carriage return
 		.replace(/\n/g, '\\n')             // line feed
-		.replace(/[\x80-\uFFFF]/g, exports.escape); // non-ASCII characters
+		.replace(/[\x00-\x1f\x80-\uFFFF]/g, exports.escape); // non-ASCII characters
+};
+
+// Turns a string into a legal JSON string
+// Derived from peg.js, thanks to David Majda
+exports.jsonStringify = function(s) {
+	// See http://www.json.org/
+	return (s || "")
+		.replace(/\\/g, '\\\\')            // backslash
+		.replace(/"/g, '\\"')              // double quote character
+		.replace(/\r/g, '\\r')             // carriage return
+		.replace(/\n/g, '\\n')             // line feed
+		.replace(/\x08/g, '\\b')           // backspace
+		.replace(/\x0c/g, '\\f')           // formfeed
+		.replace(/\t/g, '\\t')             // tab
+		.replace(/[\x00-\x1f\x80-\uFFFF]/g,function(s) {
+			return '\\u' + $tw.utils.pad(s.charCodeAt(0).toString(16).toUpperCase(),4);
+		}); // non-ASCII characters
 };
 
 /*
diff --git a/editions/tw5.com/tiddlers/filters/examples/stringify_Operator_(Examples).tid b/editions/tw5.com/tiddlers/filters/examples/stringify_Operator_(Examples).tid
index 8e33bc6be..1378287f5 100644
--- a/editions/tw5.com/tiddlers/filters/examples/stringify_Operator_(Examples).tid
+++ b/editions/tw5.com/tiddlers/filters/examples/stringify_Operator_(Examples).tid
@@ -1,7 +1,7 @@
 created: 20161017154944352
-modified: 20161017155350400
+modified: 20171029155233487
 tags: [[Operator Examples]] [[stringify Operator]]
 title: stringify Operator (Examples)
 type: text/vnd.tiddlywiki
 
-<<.operator-example 1 """[[Title with "double quotes" and \backslash]] +[stringify[]]""">>
+<<.operator-example 1 """[[Title with "double quotes" and single ' and \backslash]] +[stringify[]]""">>
diff --git a/editions/tw5.com/tiddlers/jsonstringify Operator (Examples).tid b/editions/tw5.com/tiddlers/jsonstringify Operator (Examples).tid
new file mode 100644
index 000000000..20f7bff75
--- /dev/null
+++ b/editions/tw5.com/tiddlers/jsonstringify Operator (Examples).tid	
@@ -0,0 +1,7 @@
+created: 20171029155046637
+modified: 20171029155227382
+tags: [[Operator Examples]] [[stringify Operator]]
+title: jsonstringify Operator (Examples)
+type: text/vnd.tiddlywiki
+
+<<.operator-example 1 """[[Title with "double quotes" and single ' and \backslash]] +[jsonstringify[]]""">>
diff --git a/editions/tw5.com/tiddlers/jsonstringify Operator.tid b/editions/tw5.com/tiddlers/jsonstringify Operator.tid
new file mode 100644
index 000000000..14ca58c3f
--- /dev/null
+++ b/editions/tw5.com/tiddlers/jsonstringify Operator.tid	
@@ -0,0 +1,14 @@
+caption: jsonstringify
+created: 20171029155051467
+from-version: 5.1.14
+modified: 20171029155143797
+op-input: a [[selection of titles|Title Selection]]
+op-output: the input with JSON string encodings applied
+op-parameter: 
+op-parameter-name: 
+op-purpose: apply JSON string encoding to a string
+tags: [[Filter Operators]] [[String Operators]]
+title: jsonstringify Operator
+type: text/vnd.tiddlywiki
+
+<<.operator-examples "jsonstringify">>