Warn about quoting in assignments to sh declaration utilities (fixes #1556)

CHANGELOG.md

@@ -11,6 +11,7 @@
 
 ### Changed
 - SC2048: Warning about $\* now also applies to ${array[\*]}
+- Quote warnings are now emitted for declaration utilities in sh
 
 
 ## v0.7.2 - 2021-04-19

src/ShellCheck/Analytics.hs

@@ -728,6 +728,7 @@ prop_checkUnquotedExpansions6 = verifyNot checkUnquotedExpansions "$(cmd)"
 prop_checkUnquotedExpansions7 = verifyNot checkUnquotedExpansions "cat << foo\n$(ls)\nfoo"
 prop_checkUnquotedExpansions8 = verifyNot checkUnquotedExpansions "set -- $(seq 1 4)"
 prop_checkUnquotedExpansions9 = verifyNot checkUnquotedExpansions "echo foo `# inline comment`"
+prop_checkUnquotedExpansions10 = verify checkUnquotedExpansions "#!/bin/sh\nexport var=$(val)"
 checkUnquotedExpansions params =
     check
   where
@@ -737,7 +738,7 @@ checkUnquotedExpansions params =
     check _ = return ()
     tree = parentMap params
     examine t contents =
-        unless (null contents || shouldBeSplit t || isQuoteFree tree t || usedAsCommandName tree t) $
+        unless (null contents || shouldBeSplit t || isQuoteFree (shellType params) tree t || usedAsCommandName tree t) $
             warn (getId t) 2046 "Quote this to prevent word splitting."
 
     shouldBeSplit t =
@@ -828,7 +829,7 @@ prop_checkDollarStar8 = verifyNot checkDollarStar "ls ${#*}"
 prop_checkDollarStar9 = verify checkDollarStar "ls ${arr[*]}"
 prop_checkDollarStar10 = verifyNot checkDollarStar "ls ${#arr[*]}"
 checkDollarStar p t@(T_NormalWord _ [T_DollarBraced id _ l])
-        | not (isStrictlyQuoteFree (parentMap p) t) = do
+        | not (isStrictlyQuoteFree (shellType p) (parentMap p) t) = do
       let str = concat (oversimplify l)
       when ("*" `isPrefixOf` str) $
             warn id 2048 "Use \"$@\" (with quotes) to prevent whitespace problems."
@@ -849,7 +850,7 @@ prop_checkUnquotedDollarAt7 = verify checkUnquotedDollarAt "for f in ${var[@]};
 prop_checkUnquotedDollarAt8 = verifyNot checkUnquotedDollarAt "echo \"${args[@]:+${args[@]}}\""
 prop_checkUnquotedDollarAt9 = verifyNot checkUnquotedDollarAt "echo ${args[@]:+\"${args[@]}\"}"
 prop_checkUnquotedDollarAt10 = verifyNot checkUnquotedDollarAt "echo ${@+\"$@\"}"
-checkUnquotedDollarAt p word@(T_NormalWord _ parts) | not $ isStrictlyQuoteFree (parentMap p) word =
+checkUnquotedDollarAt p word@(T_NormalWord _ parts) | not $ isStrictlyQuoteFree (shellType p) (parentMap p) word =
     forM_ (find isArrayExpansion parts) $ \x ->
         unless (isQuotedAlternativeReference x) $
             err (getId x) 2068
@@ -862,7 +863,7 @@ prop_checkConcatenatedDollarAt3 = verify checkConcatenatedDollarAt "echo $a$@"
 prop_checkConcatenatedDollarAt4 = verifyNot checkConcatenatedDollarAt "echo $@"
 prop_checkConcatenatedDollarAt5 = verifyNot checkConcatenatedDollarAt "echo \"${arr[@]}\""
 checkConcatenatedDollarAt p word@T_NormalWord {}
-    | not $ isQuoteFree (parentMap p) word
+    | not $ isQuoteFree (shellType p) (parentMap p) word
     || null (drop 1 parts) =
         mapM_ for array
   where
@@ -1891,6 +1892,7 @@ prop_checkSpacefulness40= verifyNotTree checkSpacefulness "a=$((x+1)); echo $a"
 prop_checkSpacefulness41= verifyNotTree checkSpacefulness "exec $1 --flags"
 prop_checkSpacefulness42= verifyNotTree checkSpacefulness "run $1 --flags"
 prop_checkSpacefulness43= verifyNotTree checkSpacefulness "$foo=42"
+prop_checkSpacefulness44= verifyTree checkSpacefulness "#!/bin/dash\nexport var=$value"
 
 data SpaceStatus = SpaceSome | SpaceNone | SpaceEmpty deriving (Eq)
 instance Semigroup SpaceStatus where
@@ -1972,7 +1974,7 @@ checkSpacefulness' onFind params t =
                   isExpansion token
                   && not (isArrayExpansion token) -- There's another warning for this
                   && not (isCountingReference token)
-                  && not (isQuoteFree parents token)
+                  && not (isQuoteFree (shellType params) parents token)
                   && not (isQuotedAlternativeReference token)
                   && not (usedAsCommandName parents token)
 
@@ -2090,7 +2092,7 @@ checkQuotesInLiterals params t =
         return $ case assignment of
           Just j
               | not (isParamTo parents "eval" expr)
-              && not (isQuoteFree parents expr)
+              && not (isQuoteFree (shellType params) parents expr)
               && not (squashesQuotes expr)
               -> [
                   makeComment WarningC j 2089 $

src/ShellCheck/AnalyzerLib.hs

@@ -287,14 +287,14 @@ isStrictlyQuoteFree = isQuoteFreeNode True
 isQuoteFree = isQuoteFreeNode False
 
 
-isQuoteFreeNode strict tree t =
+isQuoteFreeNode strict shell tree t =
     isQuoteFreeElement t ||
-        headOrDefault False (mapMaybe isQuoteFreeContext (drop 1 $ getPath tree t))
+        (fromMaybe False $ msum $ map isQuoteFreeContext $ drop 1 $ getPath tree t)
   where
     -- Is this node self-quoting in itself?
     isQuoteFreeElement t =
         case t of
-            T_Assignment {} -> True
+            T_Assignment {} -> assignmentIsQuoting t
             T_FdRedirect {} -> True
             _               -> False
 
@@ -306,7 +306,7 @@ isQuoteFreeNode strict tree t =
             TC_Binary _ DoubleBracket _ _ _ -> return True
             TA_Sequence {}                  -> return True
             T_Arithmetic {}                 -> return True
-            T_Assignment {}                 -> return True
+            T_Assignment {}                 -> return $ assignmentIsQuoting t
             T_Redirecting {}                -> return False
             T_DoubleQuoted _ _              -> return True
             T_DollarDoubleQuoted _ _        -> return True
@@ -318,6 +318,18 @@ isQuoteFreeNode strict tree t =
             T_SelectIn {}                   -> return (not strict)
             _                               -> Nothing
 
+    -- Check whether this assigment is self-quoting due to being a recognized
+    -- assignment passed to a Declaration Utility. This will soon be required
+    -- by POSIX: https://austingroupbugs.net/view.php?id=351
+    assignmentIsQuoting t = shellParsesParamsAsAssignments || not (isAssignmentParamToCommand t)
+    shellParsesParamsAsAssignments = shell /= Sh
+
+    -- Is this assignment a parameter to a command like export/typeset/etc?
+    isAssignmentParamToCommand (T_Assignment id _ _ _ _) =
+        case Map.lookup id tree of
+            Just (T_SimpleCommand _ _ (_:args)) -> id `elem` (map getId args)
+            _ -> False
+
 -- Check if a token is a parameter to a certain command by name:
 -- Example: isParamTo (parentMap params) "sed" t
 isParamTo :: Map.Map Id Token -> String -> Token -> Bool