1 files changed, 75 insertions, 0 deletions
diff --git a/libraries/base/tests/T13896.hs b/libraries/base/tests/T13896.hs
new file mode 100644
index 0000000000..9e269a4a7c
--- /dev/null
+++ b/libraries/base/tests/T13896.hs
@@ -0,0 +1,75 @@
+import GHC.ResponseFile
+
+assertEqual :: (Eq a, Show a) => a -> a -> IO ()
+assertEqual x y = if x == y
+                  then return ()
+                  else error $ "assertEqual: " ++ show x ++ " /= " ++ show y
+
+-- Migrated from Haddock.
+
+-- The first two elements are
+--   1) a list of 'args' to encode and
+--   2) a single string of the encoded args
+-- The 3rd element is just a description for the tests.
+testStrs :: [(([String], String), String)]
+testStrs =
+  [ ((["a simple command line"],
+      "a\\ simple\\ command\\ line\n"),
+     "the white-space, end with newline")
+
+  , ((["arg 'foo' is single quoted"],
+      "arg\\ \\'foo\\'\\ is\\ single\\ quoted\n"),
+     "the single quotes as well")
+
+  , ((["arg \"bar\" is double quoted"],
+      "arg\\ \\\"bar\\\"\\ is\\ double\\ quoted\n"),
+     "the double quotes as well" )
+
+  , ((["arg \"foo bar\" has embedded whitespace"],
+      "arg\\ \\\"foo\\ bar\\\"\\ has\\ embedded\\ whitespace\n"),
+     "the quote-embedded whitespace")
+
+  , ((["arg 'Jack said \\'hi\\'' has single quotes"],
+      "arg\\ \\'Jack\\ said\\ \\\\\\'hi\\\\\\'\\'\\ has\\ single\\ quotes\n"),
+     "the escaped single quotes")
+
+  , ((["arg 'Jack said \\\"hi\\\"' has double quotes"],
+      "arg\\ \\'Jack\\ said\\ \\\\\\\"hi\\\\\\\"\\'\\ has\\ double\\ quotes\n"),
+     "the escaped double quotes")
+
+  , ((["arg 'Jack said\\r\\n\\t \\\"hi\\\"' has other whitespace"],
+      "arg\\ \\'Jack\\ said\\\\r\\\\n\\\\t\\ \\\\\\\"hi\\\\\\\"\\'\\ has\\ \
+           \other\\ whitespace\n"),
+     "the other whitespace")
+
+  , (([ "--prologue=.\\dist\\.\\haddock-prologue3239114604.txt"
+      , "--title=HaddockNewline-0.1.0.0: This has a\n\
+        \newline yo."
+      , "-BC:\\Program Files\\Haskell Platform\\lib"],
+      "--prologue=.\\\\dist\\\\.\\\\haddock-prologue3239114604.txt\n\
+      \--title=HaddockNewline-0.1.0.0:\\ This\\ has\\ a\\\n\
+      \newline\\ yo.\n\
+      \-BC:\\\\Program\\ Files\\\\Haskell\\ Platform\\\\lib\n"),
+     "an actual haddock response file snippet with embedded newlines")
+  ]
+
+main :: IO ()
+main = do
+  -- Test escapeArgs
+  mapM_ (\((ss1,s2),des) -> escapeArgs ss1 `assertEqual` s2) testStrs
+
+  -- Test unescapeArgs
+  mapM_ (\((ss1,s2),des) -> unescapeArgs s2 `assertEqual` ss1) testStrs
+
+  -- Given unescaped quotes, it should pass-through,
+  -- without escaping everything inside
+
+  (filter (not . null) $
+   unescapeArgs "this\\ is\\ 'not escape\\d \"inside\"'\\ yo\n")
+   `assertEqual`
+   ["this is not escaped \"inside\" yo"]
+
+  (filter (not . null) $
+   unescapeArgs "this\\ is\\ \"not escape\\d 'inside'\"\\ yo\n")
+   `assertEqual`
+   ["this is not escaped 'inside' yo"]