Removed unnecessary source map generation during require() and made stack line number patching on by default.

src/coffee-script.coffee

@@ -15,6 +15,8 @@ SourceMap     = require './sourcemap'
 # The current CoffeeScript version number.
 exports.VERSION = '1.6.3'
 
+extensions = ['.coffee', '.litcoffee', '.coffee.md']
+
 # Expose helpers for testing.
 exports.helpers = helpers
 
@@ -84,7 +86,7 @@ exports.nodes = (source, options) ->
 # setting `__filename`, `__dirname`, and relative `require()`.
 exports.run = (code, options = {}) ->
   mainModule = require.main
-  options.sourceMap ?= true
+
   # Set the filename.
   mainModule.filename = process.argv[1] =
     if options.filename then fs.realpathSync(options.filename) else '.'
@@ -97,14 +99,10 @@ exports.run = (code, options = {}) ->
 
   # Compile.
   if not helpers.isCoffee(mainModule.filename) or require.extensions
-    answer = compile(code, options)
-    # Attach sourceMap object to sourceMaps[options.filename] so that
-    # it is accessible by Error.prepareStackTrace.
-    do patchStackTrace
-    sourceMaps[mainModule.filename] = answer.sourceMap
-    mainModule._compile answer.js, mainModule.filename
-  else
-    mainModule._compile code, mainModule.filename
+    answer = compile code, options
+    code = answer.js? and answer.js or answer
+
+  mainModule._compile code, mainModule.filename
 
 # Compile and evaluate a string of CoffeeScript (in a Node.js-like environment).
 # The CoffeeScript REPL uses this to run the input.
@@ -142,12 +140,12 @@ exports.eval = (code, options = {}) ->
   else
     vm.runInContext js, sandbox
 
-# Load and run a CoffeeScript file for Node, stripping any `BOM`s.
-loadFile = (module, filename) ->
+compileFile = (filename, sourceMap) ->
   raw = fs.readFileSync filename, 'utf8'
   stripped = if raw.charCodeAt(0) is 0xFEFF then raw.substring 1 else raw
+
   try
-    answer = compile(stripped, {filename, sourceMap: true, literate: helpers.isLiterate filename})
+    answer = compile(stripped, {filename, sourceMap, literate: helpers.isLiterate filename})
   catch err
     # As the filename and code of a dynamically loaded file will be different
     # from the original file compiled with CoffeeScript.run, add that
@@ -155,13 +153,18 @@ loadFile = (module, filename) ->
     err.filename = filename
     err.code = stripped
     throw err
-  sourceMaps[filename] = answer.sourceMap
-  module._compile answer.js, filename
+
+  answer
+
+# Load and run a CoffeeScript file for Node, stripping any `BOM`s.
+loadFile = (module, filename) ->
+  answer = compileFile filename, false
+  module._compile answer, filename
 
 # If the installed version of Node supports `require.extensions`, register
 # CoffeeScript as an extension.
 if require.extensions
-  for ext in ['.coffee', '.litcoffee', '.coffee.md']
+  for ext in extensions
     require.extensions[ext] = loadFile
 
   # Patch Node's module loader to be able to handle mult-dot extensions.
@@ -219,7 +222,6 @@ parser.lexer =
     @pos = 0
   upcomingInput: ->
     ""
-
 # Make all the AST nodes visible to the parser.
 parser.yy = require './nodes'
 
@@ -233,38 +235,6 @@ parser.yy.parseError = (message, {token}) ->
   # from the lexer.
   helpers.throwSyntaxError message, parser.lexer.yylloc
 
-# Based on [michaelficarra/CoffeeScriptRedux](http://goo.gl/ZTx1p)
-# NodeJS / V8 have no support for transforming positions in stack traces using
-# sourceMap, so we must monkey-patch Error to display CoffeeScript source
-# positions.
-
-patched = false
-
-# Map of filenames -> sourceMap object.
-sourceMaps = {}
-
-patchStackTrace = ->
-  return if patched
-  patched = true
-
-  # (Assigning to a property of the Module object in the normal module cache is
-  # unsuitable, because node deletes those objects from the cache if an
-  # exception is thrown in the module body.)
-
-  Error.prepareStackTrace = (err, stack) ->
-    sourceFiles = {}
-
-    getSourceMapping = (filename, line, column) ->
-      sourceMap = sourceMaps[filename]
-      answer = sourceMap.sourceLocation [line - 1, column - 1] if sourceMap
-      if answer then [answer[0] + 1, answer[1] + 1] else null
-
-    frames = for frame in stack
-      break if frame.getFunction() is exports.run
-      "  at #{formatSourcePosition frame, getSourceMapping}"
-
-    "#{err.name}: #{err.message ? ''}\n#{frames.join '\n'}\n"
-
 # Based on http://v8.googlecode.com/svn/branches/bleeding_edge/src/messages.js
 # Modified to handle sourceMap
 formatSourcePosition = (frame, getSourceMapping) ->
@@ -293,7 +263,6 @@ formatSourcePosition = (frame, getSourceMapping) ->
       else
         "#{fileName}:#{line}:#{column}"
 
-
   functionName = frame.getFunctionName()
   isConstructor = frame.isConstructor()
   isMethodCall = not (frame.isToplevel() or isConstructor)
@@ -319,3 +288,29 @@ formatSourcePosition = (frame, getSourceMapping) ->
   else
     fileLocation
 
+# Map of filenames -> sourceMap object.
+sourceMaps = {}
+
+# Generates the source map for a coffee file and stores it in the local cache variable.
+getSourceMap = (filename) ->
+  return sourceMaps[filename] if sourceMaps[filename]
+  return unless path.extname(filename) in extensions
+  answer = compileFile filename, true
+  sourceMaps[filename] = answer.sourceMap
+
+# Based on [michaelficarra/CoffeeScriptRedux](http://goo.gl/ZTx1p)
+# NodeJS / V8 have no support for transforming positions in stack traces using
+# sourceMap, so we must monkey-patch Error to display CoffeeScript source
+# positions.
+Error.prepareStackTrace = (err, stack) ->
+  getSourceMapping = (filename, line, column) ->
+    sourceMap = getSourceMap filename
+    answer = sourceMap.sourceLocation [line - 1, column - 1] if sourceMap
+    if answer then [answer[0] + 1, answer[1] + 1] else null
+
+  frames = for frame in stack
+    break if frame.getFunction() is exports.run
+    "  at #{formatSourcePosition frame, getSourceMapping}"
+
+  "#{err.name}: #{err.message ? ''}\n#{frames.join '\n'}\n"
+

test/error_messages.coffee

@@ -43,6 +43,10 @@ test "compiler error formatting", ->
                  ^^^^
   '''
 
+test "patchStackTrace line patching", ->
+  err = new Error 'error'
+  ok err.stack.indexOf('test/error_messages.coffee:47:4') >= 0 # should be fixed to the correct line if more lines added to this file
+
 fs = require 'fs'
 
 test "#2849: compilation error in a require()d file", ->