Make SC2230 optional

CHANGELOG.md

@@ -9,6 +9,9 @@
 - SC2255: Suggest using `$((..))` in `[ 2*3 -eq 6 ]`
 - SC2256: Warn about translated strings that are known variables
 
+### Changed
+- SC2230: This check is now off by default
+
 ## v0.7.0 - 2019-07-28
 ### Added
 - Precompiled binaries for macOS and Linux aarch64

shellcheck.1.md

@@ -275,8 +275,8 @@ Here is an example `.shellcheckrc`:
     # Turn on warnings for unassigned uppercase variables
     enable=check-unassigned-uppercase
 
-    # Allow using `which` since it gives full paths and is common enough
+    # Allow [ ! -z foo ] instead of suggesting -n
-    disable=SC2230
+    disable=SC2236
 
 If no `.shellcheckrc` is found in any of the parent directories, ShellCheck
 will look in `~/.shellcheckrc` followed by the XDG config directory

src/ShellCheck/Analyzer.hs

@@ -35,17 +35,18 @@ analyzeScript spec = newAnalysisResult {
     arComments =
         filterByAnnotation spec params . nub $
             runAnalytics spec
-            ++ runChecker params (checkers params)
+            ++ runChecker params (checkers spec params)
 }
   where
     params = makeParameters spec
 
-checkers params = mconcat $ map ($ params) [
+checkers spec params = mconcat $ map ($ params) [
-    ShellCheck.Checks.Commands.checker,
+    ShellCheck.Checks.Commands.checker spec,
     ShellCheck.Checks.Custom.checker,
     ShellCheck.Checks.ShellSupport.checker
     ]
 
 optionalChecks = mconcat $ [
-    ShellCheck.Analytics.optionalChecks
+    ShellCheck.Analytics.optionalChecks,
+    ShellCheck.Checks.Commands.optionalChecks
     ]

src/ShellCheck/Checks/Commands.hs

@@ -21,7 +21,7 @@
 {-# LANGUAGE FlexibleContexts #-}
 
 -- This module contains checks that examine specific commands by name.
-module ShellCheck.Checks.Commands (checker , ShellCheck.Checks.Commands.runTests) where
+module ShellCheck.Checks.Commands (checker, optionalChecks, ShellCheck.Checks.Commands.runTests) where
 
 import ShellCheck.AST
 import ShellCheck.ASTLib
@@ -90,13 +90,30 @@ commandChecks = [
     ,checkMvArguments, checkCpArguments, checkLnArguments
     ,checkFindRedirections
     ,checkReadExpansions
-    ,checkWhich
     ,checkSudoRedirect
     ,checkSudoArgs
     ,checkSourceArgs
     ,checkChmodDashr
     ]
 
+optionalChecks = map fst optionalCommandChecks
+optionalCommandChecks :: [(CheckDescription, CommandCheck)]
+optionalCommandChecks = [
+    (newCheckDescription {
+        cdName = "deprecate-which",
+        cdDescription = "Suggest 'command -v' instead of 'which'",
+        cdPositive = "which javac",
+        cdNegative = "command -v javac"
+    }, checkWhich)
+    ]
+optionalCheckMap = Map.fromList $ map (\(desc, check) -> (cdName desc, check)) optionalCommandChecks
+
+prop_verifyOptionalExamples = all check optionalCommandChecks
+  where
+    check (desc, check) =
+      verify check (cdPositive desc)
+      && verifyNot check (cdNegative desc)
+
 buildCommandMap :: [CommandCheck] -> Map.Map CommandName (Token -> Analysis)
 buildCommandMap = foldl' addCheck Map.empty
   where
@@ -128,8 +145,14 @@ getChecker list = Checker {
     map = buildCommandMap list
 
 
-checker :: Parameters -> Checker
+checker :: AnalysisSpec -> Parameters -> Checker
-checker params = getChecker commandChecks
+checker spec params = getChecker $ commandChecks ++ optionals
+  where
+    keys = asOptionalChecks spec
+    optionals =
+        if "all" `elem` keys
+        then map snd optionalCommandChecks
+        else mapMaybe (\x -> Map.lookup x optionalCheckMap) keys
 
 prop_checkTr1 = verify checkTr "tr [a-f] [A-F]"
 prop_checkTr2 = verify checkTr "tr 'a-z' 'A-Z'"