revert decision of supporting older node to allow for migration, update doc

Author: noogen

.travis.yml

@@ -1,5 +1,7 @@
 language: node_js
 node_js:
+  - '6'
+  - '8'
   - '10'
   - '12'
   - '13'

bin/text-file-diff

@@ -1,5 +1,5 @@
 #!/usr/bin/env node
-const LargeFileDiff = require('../index.js');
+const TextFileDiff = require('../index.js');
 
 const argv = process.argv;
 
@@ -12,7 +12,7 @@ if (argv.length < 4) {
 const file1 = argv[2];
 const file2 = argv[3];
 
-const lfd = new LargeFileDiff({
+const lfd = new TextFileDiff({
   skipHeader: argv.skipHeader
 });
 

index.js

@@ -8,8 +8,8 @@ const ReadlinesSync = require('n-readlines');
  * @return Number       0 for equals, 1 if line1 > line2 or -1
  */
 function defaultLineComparer(line1, line2) {
-  line1 = String(line1).trim();
-  line2 = String(line2).trim();
+  line1 = String(line1);
+  line2 = String(line2);
   return line1 > line2 ? 1 : (line1 < line2 ? -1 : 0);
 }
 
@@ -47,7 +47,7 @@ class TextFileDiff extends EventEmitter {
    * @param  Object options the options option
    * @return Object         self
    */
-  constructor(options) {
+  constructor(options={}) {
     super();
     Object.assign(this, options);
     return this;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "text-file-diff",
-  "version": "1.1.0",
+  "version": "1.1.1",
   "description": "line by line diff of two large files",
   "license": "MIT",
   "repository": "niiknow/text-file-diff",
@@ -10,7 +10,7 @@
     "url": "niiknow.org"
   },
   "engines": {
-    "node": ">=10"
+    "node": ">=6"
   },
   "scripts": {
     "test": "xo && nyc ava",

readme.md

@@ -48,6 +48,11 @@ m.on('+', line => {
 m.diff('tests/file1.txt', 'tests/file2.txt');
 ```
 
+**TextFileDiff** constructor also accept optional options object.  Valid options are:
+1. `skipHeader` - boolean indicating if first line should be skipped
+2. `charset` - default to `utf8`
+3. `compareFn` - line comparer function that take in two line (line1 and line2), and `return line1 > line2 ? 1 : (line1 < line2 ? -1 : 0)` allowing you to define how you want to perform line compare.
+
 ## Example
 ```bash
 $ ./bin/text-file-diff tests/file1.txt tests/file2.txt