fix: handle escape characters in normalized path properly (#57)

CHANGELOG.md

@@ -4,8 +4,9 @@ All notable changes to this package are documented in this file. This project ad
 
 ## Unreleased
 
-- #50, Fix wrong normalized path with descendant segment
 - #43, Fix spaces not allowed in relative query and singular query segments
+- #50, Fix wrong normalized path with descendant segment
+- #30, Fix escape characters not handled properly in normalized path
 
 ## 0.3.0.1
 

src/Data/Aeson/JSONPath/Query/Segment.hs

@@ -72,7 +72,21 @@ allElemsRecursiveLocated (loc, a@(JSON.Array arr)) = V.concat [
 allElemsRecursiveLocated _ = V.empty
 
 toPathKey :: String -> KM.Key -> String
-toPathKey loc key = loc ++ "['" ++ K.toString key ++ "']"
+toPathKey loc key = loc ++ "['" ++ escapeEscapees (K.toString key) ++ "']"
+  where
+    escapeEscapees :: String -> String
+    escapeEscapees [] = []
+    escapeEscapees (x:xs) = checkChar x ++ escapeEscapees xs
+      where
+        -- TODO: Do we need to escape unicode chars?
+        checkChar '\\' = ['\\', '\\']
+        checkChar '\'' = ['\\', '\'']
+        checkChar '\b' = ['\\', 'b']
+        checkChar '\r' = ['\\', 'r']
+        checkChar '\t' = ['\\', 't']
+        checkChar '\f' = ['\\', 'f']
+        checkChar '\n' = ['\\', 'n']
+        checkChar c = [c]
 
 toPathIdx :: String -> Int -> String
 toPathIdx loc idx = loc ++ "[" ++ show idx ++ "]"

src/Data/Aeson/JSONPath/Query/Selector.hs

@@ -122,4 +122,18 @@ sliceArrayLocated (start,end,step) vec =
 
 
 toPathKey :: String -> Text -> String
-toPathKey loc key = loc ++ "['" ++ T.unpack key ++ "']"
+toPathKey loc key = loc ++ "['" ++ escapeEscapees (T.unpack key) ++ "']"
+  where
+    escapeEscapees :: String -> String
+    escapeEscapees [] = []
+    escapeEscapees (x:xs) = checkChar x ++ escapeEscapees xs
+      where
+        -- TODO: Do we need to escape unicode chars?
+        checkChar '\\' = ['\\', '\\']
+        checkChar '\'' = ['\\', '\'']
+        checkChar '\b' = ['\\', 'b']
+        checkChar '\r' = ['\\', 'r']
+        checkChar '\t' = ['\\', 't']
+        checkChar '\f' = ['\\', 'f']
+        checkChar '\n' = ['\\', 'n']
+        checkChar c = [c]

test/compliance/ComplianceSpec.hs

@@ -11,7 +11,7 @@ import qualified Text.ParserCombinators.Parsec as P
 
 import Control.Monad              (mzero)
 import Data.Aeson                 ((.:),(.:?),Value)
-import Data.Aeson.JSONPath        (query)
+import Data.Aeson.JSONPath        (query, queryLocated)
 import Data.Aeson.JSONPath.Parser (pQuery)
 import Data.Either                (isLeft, fromRight)
 import Data.Vector                (Vector)
@@ -77,17 +77,17 @@ runTestCase TestCase{invalidSel=(Just True), ..} =
     P.parse pQuery "" selector `shouldSatisfy` isLeft
 
 -- if result is deterministic (one json)
-runTestCase TestCase{result=(Just r), {-resultPaths=(Just rp),-} document=(Just doc), ..} =
+runTestCase TestCase{result=(Just r), resultPaths=(Just rp), document=(Just doc), ..} =
   it name $ do
     query selector doc `shouldBe` Right r
-    -- queryLocated selector doc `shouldBe` Right (V.zip rp r)
+    queryLocated selector doc `shouldBe` Right (V.zip rp r)
 
 -- if result is non-deterministic (any json from the list of results)
-runTestCase TestCase{results=(Just rs), {-resultsPaths=(Just rsp),-} document=(Just doc), ..} = do
+runTestCase TestCase{results=(Just rs), resultsPaths=(Just rsp), document=(Just doc), ..} = do
   it name $ do
     query selector doc `shouldSatisfy` (\x -> fromRight V.empty x `elem` rs)
-    -- queryLocated selector doc `shouldSatisfy` (\x -> fromRight V.empty x `elem` vecList)
+    queryLocated selector doc `shouldSatisfy` (\x -> fromRight V.empty x `elem` vecList)
     where
-      -- vecList = [ V.zip rp r | rp <- rsp, r <- rs]
+      vecList = [ V.zip rp r | rp <- rsp, r <- rs]
 
 runTestCase _ = pure ()