check for duplicate file names and error

Author: phildotdev

lib/index.js

@@ -43,6 +43,11 @@ function plugin (opts) {
         var theKey = fileName.replace(/\.[^/.]+$/, '')
         var theContents = fs.readFileSync(file, 'utf8')
 
+        // Error if the key already exists (duplicate file name)
+        if (theKey in metadata) {
+          return done(new Error('Duplicate file name: ' + fileName))
+        }
+
         // Ignore file if it is empty
         if (theContents.length === 0) {
           return done()
@@ -52,7 +57,7 @@ function plugin (opts) {
         try {
           var json = JSON.parse(theContents)
         } catch (error) {
-          return done(new Error('Malformed data in ' + fileName))
+          return done(new Error('Malformed data in: ' + fileName))
         }
 
         // Debug information

test/fixtures/json-duplicate/src/example.json

@@ -0,0 +1,3 @@
+{
+  "text": "Text from a json file"
+}

test/fixtures/json-duplicate/src/subdirectory/example.json

@@ -0,0 +1,3 @@
+{
+  "random": "same key but different text"
+}

test/index.js

@@ -48,7 +48,18 @@ it('should error if a JSON file is malformed', function (done) {
   metalsmith.build(function(err) {
     errMessage = String(err);
     err.should.be.an('error')
-    errMessage.should.equal('Error: Malformed data in example.json')
+    errMessage.should.equal('Error: Malformed data in: example.json')
+
+    done() // don't return the error to metalsmith
+  })
+})
+
+it('should error if a key is already used', function (done) {
+  var metalsmith = Metalsmith('test/fixtures/json-duplicate').use(metadata({ directory: 'test/fixtures/json-duplicate/src/**/*.json' }))
+  metalsmith.build(function(err) {
+    errMessage = String(err);
+    err.should.be.an('error')
+    errMessage.should.equal('Error: Duplicate file name: example.json')
 
     done() // don't return the error to metalsmith
   })