Adds a #shellcheck source=file directive to override source statements.

ShellCheck/AST.hs

@@ -128,7 +128,7 @@ data Token =
     | T_Include Id Token Token -- . & source: SimpleCommand T_Script
     deriving (Show)
 
-data Annotation = DisableComment Integer deriving (Show, Eq)
+data Annotation = DisableComment Integer | SourceOverride String deriving (Show, Eq)
 data ConditionType = DoubleBracket | SingleBracket deriving (Show, Eq)
 
 -- This is an abomination.

ShellCheck/Checker.hs

@@ -86,11 +86,13 @@ getErrors sys spec =
   where
     getCode (PositionedComment _ (Comment _ code _)) = code
 
-check str =
+check = checkWithIncludes []
+
+checkWithIncludes includes src =
     getErrors
-        (mockedSystemInterface [])
+        (mockedSystemInterface includes)
         emptyCheckSpec {
-            csScript = str,
+            csScript = src,
             csExcludedWarnings = [2148]
         }
 
@@ -124,45 +126,34 @@ prop_optionDisablesIssue2 =
                     csExcludedWarnings = [2148, 1037]
                 }
 
+prop_canParseDevNull =
+    [] == check "source /dev/null"
+
 prop_failsWhenNotSourcing =
-    [1091, 2154] == getErrors
-                (mockedSystemInterface [])
-                emptyCheckSpec {
-                    csScript = "source lob; echo \"$bar\"",
-                    csExcludedWarnings = [2148]
-                }
+    [1091, 2154] == check "source lol; echo \"$bar\""
 
 prop_worksWhenSourcing =
-    null $ getErrors
-                (mockedSystemInterface [("lib", "bar=1")])
-                emptyCheckSpec {
-                    csScript = "source lib; echo \"$bar\"",
-                    csExcludedWarnings = [2148]
-                }
+    null $ checkWithIncludes [("lib", "bar=1")] "source lib; echo \"$bar\""
 
 prop_worksWhenDotting =
-    null $ getErrors
-                (mockedSystemInterface [("lib", "bar=1")])
-                emptyCheckSpec {
-                    csScript = ". lib; echo \"$bar\"",
-                    csExcludedWarnings = [2148]
-                }
+    null $ checkWithIncludes [("lib", "bar=1")] ". lib; echo \"$bar\""
 
 prop_noInfiniteSourcing =
-    [] == getErrors
-                (mockedSystemInterface [("lib", "source lib")])
-                emptyCheckSpec {
-                    csScript = "source lib",
-                    csExcludedWarnings = [2148]
-                }
+    [] == checkWithIncludes  [("lib", "source lib")] "source lib"
 
 prop_canSourceBadSyntax =
-    [1094, 2086] == getErrors
-                (mockedSystemInterface [("lib", "for f; do")])
-               emptyCheckSpec {
-                    csScript = "source lib; echo $1",
-                    csExcludedWarnings = [2148]
-                }
+    [1094, 2086] == checkWithIncludes [("lib", "for f; do")] "source lib; echo $1"
+
+prop_cantSourceDynamic =
+    [1090] == checkWithIncludes [("lib", "")] ". \"$1\""
+
+prop_canSourceDynamicWhenRedirected =
+    null $ checkWithIncludes [("lib", "")] "#shellcheck source=lib\n. \"$1\""
+
+prop_sourceDirectiveDoesntFollowFile =
+    null $ checkWithIncludes
+                [("foo", "source bar"), ("bar", "baz=3")]
+                "#shellcheck source=foo\n. \"$1\"; echo \"$baz\""
 
 return []
 runTests = $quickCheckAll

ShellCheck/Parser.hs

@@ -32,6 +32,7 @@ import Data.Char
 import Data.Functor
 import Data.List (isPrefixOf, isInfixOf, isSuffixOf, partition, sortBy, intercalate, nub)
 import Data.Maybe
+import Data.Monoid
 import Debug.Trace
 import GHC.Exts (sortWith)
 import Prelude hiding (readList)
@@ -191,6 +192,7 @@ shouldIgnoreCode code = do
     disabling (ContextSource _) = True -- Don't add messages for sourced files
     disabling _ = False
     disabling' (DisableComment n) = code == n
+    disabling' _ = False
 
 shouldFollow file = do
     context <- getCurrentContexts
@@ -209,6 +211,18 @@ shouldFollow file = do
     isThisFile (ContextSource name) | name == file = True
     isThisFile _= False
 
+getSourceOverride = do
+    context <- getCurrentContexts
+    return . msum . map findFile $ takeWhile isSameFile context
+  where
+    isSameFile (ContextSource _) = False
+    isSameFile _ = True
+
+    findFile (ContextAnnotation list) = msum $ map getFile list
+    findFile _ = Nothing
+    getFile (SourceOverride str) = Just str
+    getFile _ = Nothing
+
 -- Store potential parse problems outside of parsec
 
 data SystemState = SystemState {
@@ -722,10 +736,11 @@ readAnnotationPrefix = do
 
 prop_readAnnotation1 = isOk readAnnotation "# shellcheck disable=1234,5678\n"
 prop_readAnnotation2 = isOk readAnnotation "# shellcheck disable=SC1234 disable=SC5678\n"
+prop_readAnnotation3 = isOk readAnnotation "# shellcheck disable=SC1234 source=/dev/null disable=SC5678\n"
 readAnnotation = called "shellcheck annotation" $ do
     try readAnnotationPrefix
     many1 linewhitespace
-    values <- many1 readDisable
+    values <- many1 (readDisable <|> readSourceOverride)
     linefeed
     many linewhitespace
     return $ concat values
@@ -737,6 +752,11 @@ readAnnotation = called "shellcheck annotation" $ do
             optional $ string "SC"
             int <- many1 digit
             return $ DisableComment (read int)
+
+    readSourceOverride = forKey "source" $ do
+        filename <- many1 $ noneOf " \n"
+        return [SourceOverride filename]
+
     forKey s p = do
         try $ string s
         char '='
@@ -1480,11 +1500,12 @@ readSimpleCommand = called "simple command" $ do
 
 readSource :: Monad m => SourcePos -> Token -> SCParser m Token
 readSource pos t@(T_Redirecting _ _ (T_SimpleCommand _ _ (cmd:file:_))) = do
-    let literalFile = getLiteralString file
+    override <- getSourceOverride
+    let literalFile = override `mplus` getLiteralString file
     case literalFile of
         Nothing -> do
-            parseNoteAt pos InfoC 1090
-                "This source will be skipped since it's not constant."
+            parseNoteAt pos WarningC 1090
+                "Can't follow non-constant source. Use a directive to specify location."
             return t
         Just filename -> do
             proceed <- shouldFollow filename
@@ -1495,7 +1516,10 @@ readSource pos t@(T_Redirecting _ _ (T_SimpleCommand _ _ (cmd:file:_))) = do
                 return t
               else do
                 sys <- Mr.ask
-                input <- system $ siReadFile sys filename
+                input <-
+                    if filename == "/dev/null" -- always allow /dev/null
+                    then return (Right "")
+                    else system $ siReadFile sys filename
                 case input of
                     Left err -> do
                         parseNoteAt pos InfoC 1091 $

shellcheck.1.md

@@ -58,7 +58,8 @@ not warn at all, as `ksh` supports decimals in arithmetic contexts.
 
 :   Follow 'source' statements even when the file is not specified as input.
     By default, `shellcheck` will only follow files specified on the command
-    line. This option allows following any file the script may `source`.
+    line (plus `/dev/null`). This option allows following any file the script
+    may `source`.
 
 # FORMATS
 
@@ -125,7 +126,12 @@ For example, to suppress SC2035 about using `./*.jpg`:
     # shellcheck disable=SC2035
     echo "Files: " *.jpg
 
-Here a shell brace group is used to suppress on multiple lines:
+To tell ShellCheck where to look for an otherwise dynamically determined file:
+
+    # shellcheck source=./lib.sh
+    source "$(find_install_dir)/lib.sh"
+
+Here a shell brace group is used to suppress a warning on multiple lines:
 
     # shellcheck disable=SC2016
     {
@@ -140,6 +146,11 @@ Valid keys are:
     The command can be a simple command like `echo foo`, or a compound command
     like a function definition, subshell block or loop.
 
+**source**
+:   Overrides the filename included by a `source`/`.` statement. This can be
+    used to tell shellcheck where to look for a file whose name is determined
+    at runtime, or to skip a source by telling it to use `/dev/null`.
+
 
 # AUTHOR
 ShellCheck is written and maintained by Vidar Holen.