using system appropriate newline when modifying files

as discussed in jspm#518

Author: bennage

.gitattributes

@@ -0,0 +1,4 @@
+###############################################################################
+# Set default behavior to automatically normalize line endings.
+###############################################################################
+* text=auto

lib/config.js

@@ -25,6 +25,10 @@ var mkdirp = require('mkdirp');
 var extend = require('./common').extend;
 var config = module.exports;
 var asp = require('rsvp').denodeify;
+var EOL = require('os').EOL;
+
+// default newline to the appropriate value for the system
+config.newLine = EOL;
 
 // given a package.json file and an override
 // calculate the package.json file jspm will see

lib/config/loader.js

@@ -322,24 +322,24 @@ Config.prototype.write = function() {
     delete cfg.bundles;
 
   if (hasProperties(cfg))
-    configContent += 'System.config(' + JSON.stringify(cfg, null, 2) + ');\n\n';
+    configContent += 'System.config(' + JSON.stringify(cfg, null, 2) + ');' + config.newLine + config.newLine;
 
   cfg.meta = meta;
   cfg.depCache = depCache;
   cfg.map = map;
   cfg.versions = versions;
 
   if (hasProperties(meta))
-    configContent += 'System.config(' + JSON.stringify({ meta: meta }, null, 2) + ');\n\n';
+    configContent += 'System.config(' + JSON.stringify({ meta: meta }, null, 2) + ');' + config.newLine + config.newLine;
 
   if (hasProperties(depCache))
-    configContent += 'System.config(' + JSON.stringify({ depCache: depCache }, null, 2) + ');\n\n';
+    configContent += 'System.config(' + JSON.stringify({ depCache: depCache }, null, 2) + ');' + config.newLine + config.newLine;
 
   if (hasProperties(map))
-    configContent += 'System.config(' + JSON.stringify({ map: map }, null, 2) + ');\n\n';
+    configContent += 'System.config(' + JSON.stringify({ map: map }, null, 2) + ');' + config.newLine + config.newLine;
 
   if (hasProperties(versions))
-    configContent += 'System.config(' + JSON.stringify({ versions: versions }, null, 2) + ');\n\n';
+    configContent += 'System.config(' + JSON.stringify({ versions: versions }, null, 2) + ');' + config.newLine + config.newLine;
 
   return asp(fs.writeFile)(this.fileName_, configContent);
 }

lib/config/package.js

@@ -209,7 +209,7 @@ PackageJSON.prototype.write = function() {
   }
 
   // NB check that the file hasn't changed since we opened it and if so, prompt
-  return asp(fs.writeFile)(this.fileName, JSON.stringify(this.originalPjson, null, 2) + '\n');
+  return asp(fs.writeFile)(this.fileName, JSON.stringify(this.originalPjson, null, 2) + config.newLine);
 }
 
 // can take an existing non-jspm package.json