Fix error spans for shebang warnings (fixes #1620)

src/ShellCheck/AST.hs

@@ -121,7 +121,7 @@ data Token =
     | T_Rbrace Id
     | T_Redirecting Id [Token] Token
     | T_Rparen Id
-    | T_Script Id String [Token]
+    | T_Script Id Token [Token] -- Shebang T_Literal, followed by script.
     | T_Select Id
     | T_SelectIn Id String [Token] [Token]
     | T_Semi Id

src/ShellCheck/Analytics.hs

@@ -534,7 +534,7 @@ indexOfSublists sub = f 0
 prop_checkShebangParameters1 = verifyTree checkShebangParameters "#!/usr/bin/env bash -x\necho cow"
 prop_checkShebangParameters2 = verifyNotTree checkShebangParameters "#! /bin/sh  -l "
 checkShebangParameters p (T_Annotation _ _ t) = checkShebangParameters p t
-checkShebangParameters _ (T_Script id sb _) =
+checkShebangParameters _ (T_Script _ (T_Literal id sb) _) =
     [makeComment ErrorC id 2096 "On most OS, shebangs can only specify a single parameter." | length (words sb) > 2]
 
 prop_checkShebang1 = verifyNotTree checkShebang "#!/usr/bin/env bash -x\necho cow"
@@ -554,7 +554,7 @@ checkShebang params (T_Annotation _ list t) =
   where
     isOverride (ShellOverride _) = True
     isOverride _ = False
-checkShebang params (T_Script id sb _) = execWriter $ do
+checkShebang params (T_Script _ (T_Literal id sb) _) = execWriter $ do
     unless (shellTypeSpecified params) $ do
         when (sb == "") $
             err id 2148 "Tips depend on target shell and yours is unknown. Add a shebang."

src/ShellCheck/AnalyzerLib.hs

@@ -206,7 +206,7 @@ containsSetE root = isNothing $ doAnalysis (guard . not . isSetE) root
   where
     isSetE t =
         case t of
-            T_Script _ str _ -> str `matches` re
+            T_Script _ (T_Literal _ str) _ -> str `matches` re
             T_SimpleCommand {}  ->
                 t `isUnqualifiedCommand` "set" &&
                     ("errexit" `elem` oversimplify t ||
@@ -252,7 +252,7 @@ determineShell fallbackShell t = fromMaybe Bash $ do
     getCandidates (T_Annotation _ annotations s) =
         map forAnnotation annotations ++
            [Just $ fromShebang s]
-    fromShebang (T_Script _ s t) = executableFromShebang s
+    fromShebang (T_Script _ (T_Literal _ s) _) = executableFromShebang s
 
 -- Given a string like "/bin/bash" or "/usr/bin/env dash",
 -- return the shell basename like "bash" or "dash"

src/ShellCheck/Parser.hs

@@ -2790,10 +2790,11 @@ readAssignmentWordExt lenient = try $ do
 
             string "=" >> return Assign
             ]
-    readEmptyLiteral = do
+
-        start <- startSpan
+readEmptyLiteral = do
-        id <- endSpan start
+    start <- startSpan
-        return $ T_Literal id ""
+    id <- endSpan start
+    return $ T_Literal id ""
 
 readArrayIndex = do
     start <- startSpan
@@ -2941,12 +2942,14 @@ prop_readShebang5 = isWarning readShebang "\n#!/bin/sh"
 prop_readShebang6 = isWarning readShebang " # Copyright \n!#/bin/bash"
 prop_readShebang7 = isNotOk readShebang "# Copyright \nfoo\n#!/bin/bash"
 readShebang = do
+    start <- startSpan
     anyShebang <|> try readMissingBang <|> withHeader
     many linewhitespace
     str <- many $ noneOf "\r\n"
+    id <- endSpan start
     optional carriageReturn
     optional linefeed
-    return str
+    return $ T_Literal id str
   where
     anyShebang = choice $ map try [
         readCorrect,
@@ -3077,7 +3080,8 @@ readScriptFile sourced = do
         readUtf8Bom
         parseProblem ErrorC 1082
             "This file has a UTF-8 BOM. Remove it with: LC_CTYPE=C sed '1s/^...//' < yourscript ."
-    sb <- option "" readShebang
+    shebang <- readShebang <|> readEmptyLiteral
+    let (T_Literal _ shebangString) = shebang
     allspacing
     annotationStart <- startSpan
     fileAnnotations <- readAnnotations
@@ -3094,19 +3098,19 @@ readScriptFile sourced = do
     let ignoreShebang = shellAnnotationSpecified || shellFlagSpecified
 
     unless ignoreShebang $
-        verifyShebang pos (getShell sb)
+        verifyShebang pos (getShell shebangString)
-    if ignoreShebang || isValidShell (getShell sb) /= Just False
+    if ignoreShebang || isValidShell (getShell shebangString) /= Just False
       then do
             commands <- withAnnotations annotations readCompoundListOrEmpty
             id <- endSpan start
             verifyEof
             let script = T_Annotation annotationId annotations $
-                            T_Script id sb commands
+                            T_Script id shebang commands
             reparseIndices script
         else do
             many anyChar
             id <- endSpan start
-            return $ T_Script id sb []
+            return $ T_Script id shebang []
 
   where
     basename s = reverse . takeWhile (/= '/') . reverse $ s