Add prettify option to $string() function. (#356)

jhorbulyk · andrew-coleman · commit 00d36d03ea0f · 2019-08-29T08:37:27.000+01:00
diff --git a/docs/string-functions.md b/docs/string-functions.md
@@ -5,7 +5,7 @@ sidebar_label: String Functions
 ---
 
 ## `$string()`
-__Signature:__ `$string(arg)`
+__Signature:__ `$string(arg, prettify)`
 
 Casts the `arg` parameter to a string using the following casting rules
 
@@ -16,9 +16,11 @@ Casts the `arg` parameter to a string using the following casting rules
 
 If `arg` is not specified (i.e. this function is invoked with no arguments), then the context value is used as the value of `arg`.
 
+If `prettify` is true, then "prettified" JSON is produced. i.e One line per field and lines will be indented based on the field depth.
+
 __Examples__
 
-- `$string(5)` => `"5"`  
+- `$string(5)` => `"5"`
 - `[1..5].$string()` => `["1", "2", "3", "4", "5"]`
 
 ## `$length()`
@@ -35,15 +37,15 @@ __Signature:__ `$substring(str, start[, length])`
 
 Returns a string containing the characters in the first parameter `str` starting at position `start` (zero-offset).  If `str` is not specified (i.e. this function is invoked with only the numeric argument(s)), then the context value is used as the value of `str`.  An error is thrown if `str` is not a string.
 
-If `length` is specified, then the substring will contain maximum `length` characters.  
+If `length` is specified, then the substring will contain maximum `length` characters.
 
 If `start` is negative then it indicates the number of characters from the end of `str`.  See [substr](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substr) for full definition.
 
 __Examples__
 
-- `$substring("Hello World", 3)` => `"lo World"`  
-- `$substring("Hello World", 3, 5)` => `"lo Wo"`  
-- `$substring("Hello World", -4)` => `"orld"`  
+- `$substring("Hello World", 3)` => `"lo World"`
+- `$substring("Hello World", 3, 5)` => `"lo Wo"`
+- `$substring("Hello World", -4)` => `"orld"`
 - `$substring("Hello World", -4, 2)` => `"or"`
 
 ## `$substringBefore()`
@@ -122,26 +124,26 @@ The `pattern` parameter can either be a string or a regular expression (regex).
 
 __Examples__
 
-- `$contains("abracadabra", "bra")` => `true`  
-- `$contains("abracadabra", /a.*a/)` => `true`  
-- `$contains("abracadabra", /ar.*a/)` => `false`  
-- `$contains("Hello World", /wo/)` => `false`  
-- `$contains("Hello World", /wo/i)` => `true`  
+- `$contains("abracadabra", "bra")` => `true`
+- `$contains("abracadabra", /a.*a/)` => `true`
+- `$contains("abracadabra", /ar.*a/)` => `false`
+- `$contains("Hello World", /wo/)` => `false`
+- `$contains("Hello World", /wo/i)` => `true`
 - `Phone[$contains(number, /^077/)]` => `{ "type": "mobile", "number": "077 7700 1234" }`
 
 ## `$split()`
 __Signature:__ `$split(str, separator [, limit])`
 
-Splits the `str` parameter into an array of substrings.  If `str` is not specified, then the context value is used as the value of `str`.  It is an error if `str` is not a string.  
+Splits the `str` parameter into an array of substrings.  If `str` is not specified, then the context value is used as the value of `str`.  It is an error if `str` is not a string.
 
 The `separator` parameter can either be a string or a regular expression (regex).  If it is a string, it specifies the characters within `str` about which it should be split.  If it is the empty string, `str` will be split into an array of single characters.  If it is a regex, it splits the string around any sequence of characters that match the regex.
 
 The optional `limit` parameter is a number that specifies the maximum number of substrings to  include in the resultant array.  Any additional substrings are discarded.  If `limit` is not  specified, then `str` is fully split with no limit to the size of the resultant array.  It is an error if `limit` is not a non-negative number.
 
 __Examples__
 
-- `$split("so many words", " ")` => `[ "so", "many", "words" ]`  
-- `$split("so many words", " ", 2)` => `[ "so", "many" ]`  
+- `$split("so many words", " ")` => `[ "so", "many", "words" ]`
+- `$split("so many words", " ", 2)` => `[ "so", "many" ]`
 - `$split("too much, punctuation. hard; to read", /[ ,.;]+/)` => `["too", "much", "punctuation", "hard", "to", "read"]`
 
 ## `$join()`
@@ -155,7 +157,7 @@ If `separator` is not specified, then it is assumed to be the empty string, i.e.
 
 __Examples__
 
-- `$join(['a','b','c'])` => `"abc"`  
+- `$join(['a','b','c'])` => `"abc"`
 - `$split("too much, punctuation. hard; to read", /[ ,.;]+/, 3) ~> $join(', ')` => `"too, much, punctuation"`
 
 ## `$match()`
@@ -278,7 +280,7 @@ __Signature:__ `$base64encode()`
 
 Converts an ASCII string to a base 64 representation. Each each character in the string is treated as a byte of binary data. This requires that all characters in the string are in the 0x00 to 0xFF range, which includes all characters in URI encoded strings. Unicode characters outside of that range are not supported.
 
-__Examples__  
+__Examples__
 
 - `$base64encode("myuser:mypass")` => `"bXl1c2VyOm15cGFzcw=="`
 
@@ -288,6 +290,6 @@ __Signature:__ `$base64decode()`
 
 Converts base 64 encoded bytes to a string, using a UTF-8 Unicode codepage.
 
-__Examples__  
+__Examples__
 
 - `$base64decode("bXl1c2VyOm15cGFzcw==")` => `"myuser:mypass"`
diff --git a/src/functions.js b/src/functions.js
@@ -97,11 +97,12 @@ const functions = (() => {
     }
 
     /**
-     * Stingify arguments
+     * Stringify arguments
      * @param {Object} arg - Arguments
+     * @param {boolean} [prettify] - Pretty print the result
      * @returns {String} String from arguments
      */
-    function string(arg) {
+    function string(arg, prettify = false) {
         // undefined inputs always return undefined
         if (typeof arg === 'undefined') {
             return undefined;
@@ -121,11 +122,13 @@ const functions = (() => {
                 value: arg,
                 stack: (new Error()).stack
             };
-        } else
+        } else {
+            var space = prettify ? 2 : 0;
             str = JSON.stringify(arg, function (key, val) {
                 return (typeof val !== 'undefined' && val !== null && val.toPrecision && isNumeric(val)) ? Number(val.toPrecision(15)) :
                     (val && isFunction(val)) ? '' : val;
-            });
+            }, space);
+        }
         return str;
     }
 
diff --git a/src/jsonata.js b/src/jsonata.js
@@ -1658,7 +1658,7 @@ var jsonata = (function() {
     staticFrame.bind('max', defineFunction(fn.max, '<a<n>:n>'));
     staticFrame.bind('min', defineFunction(fn.min, '<a<n>:n>'));
     staticFrame.bind('average', defineFunction(fn.average, '<a<n>:n>'));
-    staticFrame.bind('string', defineFunction(fn.string, '<x-:s>'));
+    staticFrame.bind('string', defineFunction(fn.string, '<x-b?:s>'));
     staticFrame.bind('substring', defineFunction(fn.substring, '<s-nn?:s>'));
     staticFrame.bind('substringBefore', defineFunction(fn.substringBefore, '<s-s:s>'));
     staticFrame.bind('substringAfter', defineFunction(fn.substringAfter, '<s-s:s>'));
diff --git a/test/test-suite/groups/function-string/case023.json b/test/test-suite/groups/function-string/case023.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string({\"string\": \"hello\"}, false)",
+    "dataset": null,
+    "bindings": {},
+    "result": "{\"string\":\"hello\"}"
+}
diff --git a/test/test-suite/groups/function-string/case024.json b/test/test-suite/groups/function-string/case024.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string({\"string\": \"hello\"}, true)",
+    "dataset": null,
+    "bindings": {},
+    "result": "{\n  \"string\": \"hello\"\n}"
+}
diff --git a/test/test-suite/groups/function-string/case025.json b/test/test-suite/groups/function-string/case025.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string([\"string\", 5], false)",
+    "dataset": null,
+    "bindings": {},
+    "result": "[\"string\",5]"
+}
diff --git a/test/test-suite/groups/function-string/case026.json b/test/test-suite/groups/function-string/case026.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string([\"string\", 5], true)",
+    "dataset": null,
+    "bindings": {},
+    "result": "[\n  \"string\",\n  5\n]"
+}
diff --git a/test/test-suite/groups/function-string/case027.json b/test/test-suite/groups/function-string/case027.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string({  \"string\": \"hello\",  \"number\": 78.8 / 2,  \"null\":null,  \"boolean\": false,  \"function\": $sum,  \"lambda\": function(){true},  \"object\": {    \"str\": \"another\",    \"lambda2\": function($n){$n}  },  \"array\": []}, false)",
+    "dataset": null,
+    "bindings": {},
+    "result": "{\"string\":\"hello\",\"number\":39.4,\"null\":null,\"boolean\":false,\"function\":\"\",\"lambda\":\"\",\"object\":{\"str\":\"another\",\"lambda2\":\"\"},\"array\":[]}"
+}
diff --git a/test/test-suite/groups/function-string/case028.json b/test/test-suite/groups/function-string/case028.json
@@ -0,0 +1,6 @@
+{
+    "expr": "$string({  \"string\": \"hello\",  \"number\": 78.8 / 2,  \"null\":null,  \"boolean\": false,  \"function\": $sum,  \"lambda\": function(){true},  \"object\": {    \"str\": \"another\",    \"lambda2\": function($n){$n}  },  \"array\": []}, true)",
+    "dataset": null,
+    "bindings": {},
+    "result": "{\n  \"string\": \"hello\",\n  \"number\": 39.4,\n  \"null\": null,\n  \"boolean\": false,\n  \"function\": \"\",\n  \"lambda\": \"\",\n  \"object\": {\n    \"str\": \"another\",\n    \"lambda2\": \"\"\n  },\n  \"array\": []\n}"
+}
