Revert changes in offset function and add calculating current offset before calculating new one.

Author: MakMuftic

src/lib/contract/contract.es6

@@ -42,7 +42,8 @@ export class Contract {
   }
 
   insertLinesBefore(lines, line) {
-    line += this.offset(line);
+    let currentOffset = this.offset(line);
+    line += this.offset(line + currentOffset);
     this.addOffset(line, lines.length);
     this.lines.splice(line, 0, ...lines);
   }
@@ -72,9 +73,10 @@ export class Contract {
     let offsetAmount = 0;
     for (let offset in this.offsets) {
       if (this.offsets.hasOwnProperty(offset)) {
-        offsetAmount += this.offsets[offset];
+          if (line >= offset)
+              offsetAmount += this.offsets[offset];
+          }
       }
-    }
     return offsetAmount;
   }
 }

test/lib/contract/contract.test.es6

@@ -60,14 +60,15 @@ test('Insert text before', (t) => {
 });
 
 test('Insert text before with offset', (t) => {
-  t.plan(5);
+  t.plan(6);
   let contract =new Contract(['line1', 'line2']);
   contract.insertTextBefore('test1\nbla', 0);
   t.equal(contract.getLineAt(0), 'test1');
   t.equal(contract.getLineAt(1), 'bla');
   t.equal(contract.offset(0), 2);
   contract.insertTextBefore('offset', 0);
-  t.equal(contract.offset(0), 3);
+  t.equal(contract.offset(0), 2);
+  t.equal(contract.offset(2), 3);
   t.equal(contract.getLineAt(2), 'offset');
 });