Fixed leading whitespace before interpolation in simple strings

xixixao · xixixao · commit a61b6ee925bb · 2013-11-27T20:29:45.000Z
diff --git a/lib/coffee-script/lexer.js b/lib/coffee-script/lexer.js
diff --git a/src/lexer.coffee b/src/lexer.coffee
@@ -186,19 +186,15 @@ exports.Lexer = class Lexer
   # Matches strings, including multi-line strings. Ensures that quotation marks
   # are balanced within the string's contents, and within nested interpolations.
   stringToken: ->
-    switch @chunk.charAt 0
-      when "'"
-        return 0 unless match = SIMPLESTR.exec @chunk
-        string = match[0]
-        @token 'STRING', @escapeLines(string), 0, string.length
-      when '"'
-        return 0 unless string = @balancedString @chunk, '"'
-        if 0 < string.indexOf '#{', 1
-          @interpolateString string[1...-1], strOffset: 1, lexedLength: string.length
-        else
-          @token 'STRING', @escapeLines(string), 0, string.length
-      else
-        return 0
+    switch quote = @chunk.charAt 0
+      when "'" then [string] = SIMPLESTR.exec @chunk
+      when '"' then string = @balancedString @chunk, '"'
+    return 0 unless string
+    trimmed = @removeNewlines string[1...-1]
+    if quote is '"' and 0 < string.indexOf '#{', 1
+      @interpolateString trimmed, strOffset: 1, lexedLength: string.length
+    else
+      @token 'STRING', quote + @escapeLines(trimmed) + quote, 0, string.length
     if octalEsc = /^(?:\\.|[^\\])*\\(?:0[0-7]|[1-7])/.test string
       @error "octal escape sequences #{string} are not allowed"
     string.length
@@ -686,6 +682,11 @@ exports.Lexer = class Lexer
     @tag() in ['\\', '.', '?.', '?::', 'UNARY', 'MATH', '+', '-', 'SHIFT', 'RELATION'
                'COMPARE', 'LOGIC', 'THROW', 'EXTENDS']
 
+  # Remove newlines from beginning and (non escaped) from end of string literals.
+  removeNewlines: (str) ->
+    str.replace(/^\s*\n\s*/, '')
+       .replace(/([^\\]|\\\\)\s*\n\s*$/, '$1')
+
   # Converts newlines for string literals.
   escapeLines: (str, heredoc) ->
     # Ignore escaped backslashes and remove escaped newlines
@@ -695,9 +696,7 @@ exports.Lexer = class Lexer
       str.replace MULTILINER, '\\n'
     else
       # Trim leading and trailing whitespace, string includes quotes
-      str.replace(/^(.)\s*\n\s*/, '$1')
-         .replace(/\s*\n\s*(.)$/, '$1')
-         .replace(/\s*\n\s*/g, ' ')
+      str.replace /\s*\n\s*/g, ' '
 
   # Constructs a string token by escaping quotes and newlines.
   makeString: (body, quote, heredoc) ->
diff --git a/test/strings.coffee b/test/strings.coffee
@@ -81,6 +81,9 @@ test "#3229, multiline strings", ->
     'string ' + "inside
                  interpolation"
     }", "a string inside interpolation"
+  eq "
+      #{1}
+     ", '1'
 
   # Handle escaped backslashes correctly.
   eq '\\', `'\\'`
@@ -155,6 +158,11 @@ test "#3249, escape newlines in heredocs with backslashes", ->
         too #{3}\
     !
   """, 'interpolation 1\n  follows 2  too 3!'
+  eq """
+
+    #{1} #{2}
+
+    """, '\n1 2\n'
 
   # TODO: uncomment when #2388 is fixed
   # eq """a heredoc #{
