Add Jison-generated JavaScript to generated files (#3393)

* Fix typos

* Add Jison-generated JavaScript to generated files

lib/linguist/generated.rb

@@ -3,7 +3,7 @@ module Linguist
     # Public: Is the blob a generated file?
     #
     # name - String filename
-    # data - String blob data. A block also maybe passed in for lazy
+    # data - String blob data. A block also may be passed in for lazy
     #        loading. This behavior is deprecated and you should always
     #        pass in a String.
     #
@@ -78,7 +78,8 @@ module Linguist
       generated_racc? ||
       generated_jflex? ||
       generated_grammarkit? ||
-      generated_roxygen2?
+      generated_roxygen2? ||
+      generated_jison?
     end
 
     # Internal: Is the blob an Xcode file?
@@ -312,7 +313,7 @@ module Linguist
       !!name.match(/vendor\/((?!-)[-0-9A-Za-z]+(?<!-)\.)+(com|edu|gov|in|me|net|org|fm|io)/)
     end
 
-    # Internal: Is the blob a generated npm shrinkwrap file.
+    # Internal: Is the blob a generated npm shrinkwrap file?
     #
     # Returns true or false.
     def npm_shrinkwrap?
@@ -334,7 +335,7 @@ module Linguist
       !!name.match(/composer\.lock/)
     end
 
-    # Internal: Is the blob a generated by Zephir
+    # Internal: Is the blob generated by Zephir?
     #
     # Returns true or false.
     def generated_by_zephir?
@@ -434,7 +435,7 @@ module Linguist
       return false unless lines.count > 1
       return lines[0].start_with?("// This is a generated file. Not intended for manual editing.")
     end
-
+        
     # Internal: Is this a roxygen2-generated file?
     #
     # A roxygen2-generated file typically contain:
@@ -448,5 +449,23 @@ module Linguist
 
       return lines[0].include?("% Generated by roxygen2: do not edit by hand")
     end
+        
+    # Internal: Is this a Jison-generated file?
+    #
+    # Jison-generated parsers typically contain:
+    # /* parser generated by jison
+    # on the first line.
+    #
+    # Jison-generated lexers typically contain:
+    # /* generated by jison-lex
+    # on the first line.
+    #
+    # Return true or false
+    def generated_jison?
+      return false unless extname == '.js'
+      return false unless lines.count > 1
+      return lines[0].start_with?("/* parser generated by jison ") ||
+              lines[0].start_with?("/* generated by jison-lex ")
+    end
   end
 end