Added a columnTransform func to transform column names

Readme.md

@@ -71,7 +71,12 @@ The options are also passed to the underlying transform stream, so you can pass
   objectMode: false,
 
   // if set to true, uses first row as keys -> [ { column1: value1, column2: value2 }, ...]
-  columns: false
+  columns: false,
+
+  // each csv column name is optionally mapped to this so its value can be transformed
+  columnTransform: function(name) {
+    return name
+  }
 }
 ```
 

csv-streamify.js

@@ -16,6 +16,7 @@ module.exports = function (opts, cb) {
   opts.empty = opts.hasOwnProperty('empty') ? opts.empty : ''
   opts.objectMode = opts.objectMode || false
   opts.hasColumns = opts.columns || false
+  opts.columnTransform = opts.columnTransform || function (l) { return l }
 
   // state
   var state = {
@@ -41,7 +42,7 @@ function createParser (opts, state) {
 
     if (opts.hasColumns) {
       if (state.lineNo === 0) {
-        state._columns = state._line
+        state._columns = state._line.map(opts.columnTransform)
         state.lineNo += 1
         reset()
         return

test/csv-streamify.js

@@ -199,3 +199,45 @@ describe('edge cases', function () {
     }))
   })
 })
+
+describe('column name transform', function () {
+  it('should transform column names', function (done) {
+    var input = 'Some Name,product_description,watchers\n'
+    input += 'SLaks/Styliner,"Turns CSS stylesheets into inline style="""" attributes for HTML emails",33\n'
+    input += 'guelfey/go.dbus,Native Go bindings for D-Bus,12'
+
+    var opts = {
+      columns: true,
+      columnTransform: function (name) {
+        switch (name) {
+          case 'Some Name':
+            return 'newName'
+          case 'product_description':
+            return 'productDescription'
+          default:
+            return name
+        }
+      }
+    }
+
+    str(input).pipe(csv(opts, function (err, res) {
+      if (err) return done(err)
+
+      assert.strictEqual(res.length, 2, 'should emit 2 lines')
+
+      assert.strictEqual(res[0].hasOwnProperty('Some Name'), false)
+      assert.strictEqual(res[0]['newName'], 'SLaks/Styliner')
+      assert.strictEqual(res[0].hasOwnProperty('product_description'), false)
+      assert.strictEqual(res[0]['productDescription'], 'Turns CSS stylesheets into inline style="" attributes for HTML emails')
+      assert.strictEqual(res[0]['watchers'], '33')
+
+      assert.strictEqual(res[1].hasOwnProperty('Some Name'), false)
+      assert.strictEqual(res[1]['newName'], 'guelfey/go.dbus')
+      assert.strictEqual(res[1].hasOwnProperty('product_description'), false)
+      assert.strictEqual(res[1]['productDescription'], 'Native Go bindings for D-Bus')
+      assert.strictEqual(res[1]['watchers'], '12')
+
+      done()
+    }))
+  })
+})