Add support for ${| ..} expansion (fixes #3243)

src/ShellCheck/AST.hs

@@ -31,6 +31,7 @@ newtype Id = Id Int deriving (Show, Eq, Ord, Generic, NFData)
 
 data Quoted = Quoted | Unquoted deriving (Show, Eq)
 data Dashed = Dashed | Undashed deriving (Show, Eq)
+data Piped = Piped | Unpiped deriving (Show, Eq)
 data AssignmentMode = Assign | Append deriving (Show, Eq)
 newtype FunctionKeyword = FunctionKeyword Bool deriving (Show, Eq)
 newtype FunctionParentheses = FunctionParentheses Bool deriving (Show, Eq)
@@ -84,7 +85,7 @@ data InnerToken t =
     | Inner_T_DollarDoubleQuoted [t]
     | Inner_T_DollarExpansion [t]
     | Inner_T_DollarSingleQuoted String
-    | Inner_T_DollarBraceCommandExpansion [t]
+    | Inner_T_DollarBraceCommandExpansion Piped [t]
     | Inner_T_Done
     | Inner_T_DoubleQuoted [t]
     | Inner_T_EOF
@@ -228,7 +229,7 @@ pattern T_CoProc id var body = OuterToken id (Inner_T_CoProc var body)
 pattern TC_Or id typ str t1 t2 = OuterToken id (Inner_TC_Or typ str t1 t2)
 pattern TC_Unary id typ op token = OuterToken id (Inner_TC_Unary typ op token)
 pattern T_DollarArithmetic id c = OuterToken id (Inner_T_DollarArithmetic c)
-pattern T_DollarBraceCommandExpansion id list = OuterToken id (Inner_T_DollarBraceCommandExpansion list)
+pattern T_DollarBraceCommandExpansion id pipe list = OuterToken id (Inner_T_DollarBraceCommandExpansion pipe list)
 pattern T_DollarBraced id braced op = OuterToken id (Inner_T_DollarBraced braced op)
 pattern T_DollarBracket id c = OuterToken id (Inner_T_DollarBracket c)
 pattern T_DollarDoubleQuoted id list = OuterToken id (Inner_T_DollarDoubleQuoted list)

src/ShellCheck/ASTLib.hs

@@ -561,7 +561,7 @@ getCommandNameFromExpansion t =
     case t of
         T_DollarExpansion _ [c] -> extract c
         T_Backticked _ [c] -> extract c
-        T_DollarBraceCommandExpansion _ [c] -> extract c
+        T_DollarBraceCommandExpansion _ _ [c] -> extract c
         _ -> Nothing
   where
     extract (T_Pipeline _ _ [cmd]) = getCommandName cmd
@@ -616,7 +616,7 @@ getCommandSequences t =
         T_Annotation _ _ t -> getCommandSequences t
 
         T_DollarExpansion _ cmds -> [cmds]
-        T_DollarBraceCommandExpansion _ cmds -> [cmds]
+        T_DollarBraceCommandExpansion _ _ cmds -> [cmds]
         T_Backticked _ cmds -> [cmds]
         _ -> []
 

src/ShellCheck/Analytics.hs

@@ -800,7 +800,7 @@ checkUnquotedExpansions params =
   where
     check t@(T_DollarExpansion _ c) = examine t c
     check t@(T_Backticked _ c) = examine t c
-    check t@(T_DollarBraceCommandExpansion _ c) = examine t c
+    check t@(T_DollarBraceCommandExpansion _ _ c) = examine t c
     check _ = return ()
     tree = parentMap params
     examine t contents =
@@ -3012,7 +3012,8 @@ checkTildeInPath _ _ = return ()
 
 prop_checkUnsupported3 = verify checkUnsupported "#!/bin/sh\ncase foo in bar) baz ;& esac"
 prop_checkUnsupported4 = verify checkUnsupported "#!/bin/ksh\ncase foo in bar) baz ;;& esac"
-prop_checkUnsupported5 = verify checkUnsupported "#!/bin/bash\necho \"${ ls; }\""
+prop_checkUnsupported5 = verifyNot checkUnsupported "#!/bin/bash\necho \"${ ls; }\""
+prop_checkUnsupported6 = verify checkUnsupported "#!/bin/ash\necho \"${ ls; }\""
 checkUnsupported params t =
     unless (null support || (shellType params `elem` support)) $
         report name
@@ -3026,7 +3027,7 @@ checkUnsupported params t =
 shellSupport t =
   case t of
     T_CaseExpression _ _ list -> forCase (map (\(a,_,_) -> a) list)
-    T_DollarBraceCommandExpansion {} -> ("${ ..; } command expansion", [Ksh])
+    T_DollarBraceCommandExpansion {} -> ("${ ..; } command expansion", [Bash, Ksh])
     _ -> ("", [])
   where
     forCase seps | CaseContinue `elem` seps = ("cases with ;;&", [Bash])
@@ -3606,7 +3607,7 @@ checkSplittingInArrays params t =
         _ -> return ()
     checkPart part = case part of
         T_DollarExpansion id _ -> forCommand id
-        T_DollarBraceCommandExpansion id _ -> forCommand id
+        T_DollarBraceCommandExpansion id _ _ -> forCommand id
         T_Backticked id _ -> forCommand id
         T_DollarBraced id _ str |
             not (isCountingReference part)
@@ -5161,7 +5162,7 @@ checkExpansionWithRedirection params t =
     case t of
         T_DollarExpansion id [cmd] -> check id cmd
         T_Backticked id [cmd] -> check id cmd
-        T_DollarBraceCommandExpansion id [cmd] -> check id cmd
+        T_DollarBraceCommandExpansion id _ [cmd] -> check id cmd
         _ -> return ()
   where
     check id pipe =

src/ShellCheck/CFG.hs

@@ -716,6 +716,9 @@ build t = do
                 linkRange totalRead result
               else return totalRead
 
+        T_DollarBraceCommandExpansion id _ body ->
+            sequentially body
+
         T_DoubleQuoted _ list -> sequentially list
 
         T_DollarExpansion id body ->

src/ShellCheck/Parser.hs

@@ -1695,16 +1695,17 @@ readAmbiguous prefix expected alternative warner = do
 
 prop_readDollarBraceCommandExpansion1 = isOk readDollarBraceCommandExpansion "${ ls; }"
 prop_readDollarBraceCommandExpansion2 = isOk readDollarBraceCommandExpansion "${\nls\n}"
-readDollarBraceCommandExpansion = called "ksh ${ ..; } command expansion" $ do
+prop_readDollarBraceCommandExpansion3 = isOk readDollarBraceCommandExpansion "${|  REPLY=42; }"
+readDollarBraceCommandExpansion = called "ksh-style ${ ..; } command expansion" $ do
     start <- startSpan
-    try $ do
-        string "${"
-        whitespace
+    c <- try $ do
+            string "${"
+            char '|' <|> whitespace
     allspacing
     term <- readTerm
-    char '}' <|> fail "Expected } to end the ksh ${ ..; } command expansion"
+    char '}' <|> fail "Expected } to end the ksh-style ${ ..; } command expansion"
     id <- endSpan start
-    return $ T_DollarBraceCommandExpansion id term
+    return $ T_DollarBraceCommandExpansion id (if c == '|' then Piped else Unpiped) term
 
 prop_readDollarBraced1 = isOk readDollarBraced "${foo//bar/baz}"
 prop_readDollarBraced2 = isOk readDollarBraced "${foo/'{cow}'}"