diff --git a/spec/stdlib/fs-spec.coffee b/spec/stdlib/fs-spec.coffee
index 5b17662a9..ffcdaf31b 100644
--- a/spec/stdlib/fs-spec.coffee
+++ b/spec/stdlib/fs-spec.coffee
@@ -33,6 +33,13 @@ describe "fs", ->
         expect(fs.directory("a")).toBe ""
         expect(fs.directory("/a/b/c++")).toBe "/a/b"
 
+  describe ".base(path, ext)", ->
+    describe "when called with an extension", ->
+      it "return the base name without the extension when the path has the given extension", ->
+        expect(fs.base("/a/b/c.txt", '.txt')).toBe "c"
+        expect(fs.base("/a/b/c.txt", '.txt2')).toBe "c.txt"
+        expect(fs.base("/a/b/c.+", '.+')).toBe "c"
+
   describe ".exists(path)", ->
     it "returns true when path exsits", ->
       expect(fs.exists(require.resolve('fixtures'))).toBe true
diff --git a/src/stdlib/fs.coffee b/src/stdlib/fs.coffee
index 054747b41..cb22ab5b1 100644
--- a/src/stdlib/fs.coffee
+++ b/src/stdlib/fs.coffee
@@ -15,7 +15,7 @@ module.exports =
   # remove a trailing extension.
   base: (path, ext) ->
     base = path.replace(/\/$/, '').split("/").pop()
-    if ext then base.replace(RegExp(ext + "$"), "") else base
+    if ext then base.replace(RegExp("#{_.escapeRegExp(ext)}$"), '') else base
 
   # Returns the path of a file's containing directory, albeit the
   # parent directory if the file is a directory. A terminal directory