replacing JSON with JSON5 for better error messaging

Author: e2tha-e

core/lib/list_item_hunter.js

@@ -13,6 +13,7 @@
 var list_item_hunter = function () {
 
   var extend = require('util')._extend,
+    JSON = require('json5'),
     pa = require('./pattern_assembler'),
     smh = require('./style_modifier_hunter'),
     pattern_assembler = new pa(),
@@ -44,7 +45,13 @@ var list_item_hunter = function () {
         }
 
         //check for a local listitems.json file
-        var listData = JSON.parse(JSON.stringify(patternlab.listitems));
+        var listData;
+        try {
+          listData = JSON.parse(JSON.stringify(patternlab.listitems));
+        } catch (err) {
+          console.log('There was an error parsing JSON for ' + pattern.abspath);
+          console.log(err);
+        }
         listData = pattern_assembler.merge_data(listData, pattern.listitems);
 
         //iterate over each copied block, rendering its contents along with pattenlab.listitems[i]
@@ -54,8 +61,15 @@ var list_item_hunter = function () {
 
           //combine listItem data with pattern data with global data
           var itemData = listData['' + items.indexOf(loopNumberString)]; //this is a property like "2"
-          var globalData = JSON.parse(JSON.stringify(patternlab.data));
-          var localData = JSON.parse(JSON.stringify(pattern.jsonFileData));
+          var globalData;
+          var localData;
+          try {
+            globalData = JSON.parse(JSON.stringify(patternlab.data));
+            localData = JSON.parse(JSON.stringify(pattern.jsonFileData));
+          } catch (err) {
+            console.log('There was an error parsing JSON for ' + pattern.abspath);
+            console.log(err);
+          }
 
           var allData = pattern_assembler.merge_data(globalData, localData);
           allData = pattern_assembler.merge_data(allData, itemData !== undefined ? itemData[i] : {}); //itemData could be undefined if the listblock contains no partial, just markup
@@ -71,7 +85,13 @@ var list_item_hunter = function () {
               var partialPattern = pattern_assembler.get_pattern_by_key(partialName, patternlab);
 
               //create a copy of the partial so as to not pollute it after the get_pattern_by_key call.
-              var cleanPartialPattern = JSON.parse(JSON.stringify(partialPattern));
+              var cleanPartialPattern;
+              try {
+                cleanPartialPattern = JSON.parse(JSON.stringify(partialPattern));
+              } catch (err) {
+                console.log('There was an error parsing JSON for ' + pattern.abspath);
+                console.log(err);
+              }
 
               //if partial has style modifier data, replace the styleModifier value
               if (foundPartials[j].indexOf(':') > -1) {

core/lib/parameter_hunter.js

@@ -13,6 +13,7 @@
 var parameter_hunter = function () {
 
   var extend = require('util')._extend,
+    JSON = require('json5'),
     pa = require('./pattern_assembler'),
     smh = require('./style_modifier_hunter'),
     pattern_assembler = new pa(),
@@ -223,8 +224,9 @@ var parameter_hunter = function () {
           paramData = JSON.parse(paramStringWellFormed);
           globalData = JSON.parse(JSON.stringify(patternlab.data));
           localData = JSON.parse(JSON.stringify(pattern.jsonFileData || {}));
-        } catch (e) {
-          console.log(e);
+        } catch (err) {
+          console.log('There was an error parsing JSON for ' + pattern.abspath);
+          console.log(err);
         }
 
         var allData = pattern_assembler.merge_data(globalData, localData);

core/lib/pattern_assembler.js

@@ -332,6 +332,7 @@ var pattern_assembler = function () {
   }
 
   function parseDataLinksHelper(patternlab, obj, key) {
+    var JSON = require('json5');
     var linkRE, dataObjAsString, linkMatches, expandedLink;
 
     linkRE = /link\.[A-z0-9-_]+/g;
@@ -349,7 +350,16 @@ var pattern_assembler = function () {
         }
       }
     }
-    return JSON.parse(dataObjAsString);
+
+    var dataObj;
+    try {
+      dataObj = JSON.parse(dataObjAsString);
+    } catch (err) {
+      console.log('There was an error parsing JSON for ' + key);
+      console.log(err);
+    }
+
+    return dataObj;
   }
 
   //look for pattern links included in data files.

core/lib/patternlab.js

@@ -12,6 +12,7 @@ var patternlab_engine = function (config) {
   'use strict';
 
   var path = require('path'),
+    JSON = require('json5'),
     fs = require('fs-extra'),
     diveSync = require('diveSync'),
     of = require('./object_factory'),
@@ -191,7 +192,13 @@ var patternlab_engine = function (config) {
       pattern.lineageR = lineageRArray;
 
       //render the pattern, but first consolidate any data we may have
-      var allData = JSON.parse(JSON.stringify(patternlab.data));
+      var allData;
+      try {
+        allData = JSON.parse(JSON.stringify(patternlab.data));
+      } catch (err) {
+        console.log('There was an error parsing JSON for ' + pattern.abspath);
+        console.log(err);
+      }
       allData = pattern_assembler.merge_data(allData, pattern.jsonFileData);
 
       //also add the cachebuster value. slight chance this could collide with a user that has defined cacheBuster as a value

test/parameter_hunter_tests.js

@@ -311,12 +311,14 @@
       patternlab.patterns[0].template = "<p>{{foo}}</p>";
       patternlab.patterns[0].extendedTemplate = patternlab.patterns[0].template;
 
+      currentPattern.abspath = __filename;
       currentPattern.template = "{{> molecules-single-comment( missing-val: , : missing-key, : , , foo: \"Hello World\") }}";
       currentPattern.extendedTemplate = currentPattern.template;
       currentPattern.parameteredPartials[0] = currentPattern.template;
 
+      console.log('\nPattern Lab should catch JSON.parse() errors and output useful debugging information...');
       parameter_hunter.find_parameters(currentPattern, patternlab);
-      test.equals(currentPattern.extendedTemplate, '<p>Hello World</p>');
+      test.equals(currentPattern.extendedTemplate, '<p></p>');
 
       test.done();
     }