Merge pull request #1662 from geraldalewis/1195_trailing_semicolons

#1195 Ignore trailing semicolons

lib/coffee-script/lexer.js

@@ -275,6 +275,9 @@
         }
       }
       if (dent) this.outdebt -= moveOut;
+      while (this.value() === ';') {
+        this.tokens.pop();
+      }
       if (!(this.tag() === 'TERMINATOR' || noNewlines)) {
         this.token('TERMINATOR', '\n');
       }
@@ -294,6 +297,9 @@
       }
     };
     Lexer.prototype.newlineToken = function() {
+      while (this.value() === ';') {
+        this.tokens.pop();
+      }
       if (this.tag() !== 'TERMINATOR') this.token('TERMINATOR', '\n');
       return this;
     };

src/lexer.coffee

@@ -279,6 +279,7 @@ exports.Lexer = class Lexer
         @outdebt = 0
         @token 'OUTDENT', dent
     @outdebt -= moveOut if dent
+    @tokens.pop() while @value() is ';'
     @token 'TERMINATOR', '\n' unless @tag() is 'TERMINATOR' or noNewlines
     this
 
@@ -293,6 +294,7 @@ exports.Lexer = class Lexer
 
   # Generate a newline token. Consecutive newlines get merged together.
   newlineToken: ->
+    @tokens.pop() while @value() is ';'
     @token 'TERMINATOR', '\n' unless @tag() is 'TERMINATOR'
     this
 

test/formatting.coffee

@@ -121,3 +121,16 @@ test "indented heredoc", ->
 test "#1492: Nested blocks don't cause double semicolons", ->
   js = CoffeeScript.compile '(0;0)'
   eq -1, js.indexOf ';;'
+
+test "#1195 Ignore trailing semicolons (before newlines or as the last char in a program)", ->
+    preNewline = (numSemicolons) ->
+      """
+      nonce = {}; nonce2 = {}
+      f = -> nonce#{Array(numSemicolons+1).join(';')}
+      nonce2
+      unless f() is nonce then throw new Error('; before linebreak should = newline')
+      """
+    CoffeeScript.run(preNewline(n), bare: true) for n in [1,2,3]
+    
+    lastChar = '-> lastChar;'
+    doesNotThrow -> CoffeeScript.compile lastChar, bare: true