From 727d940e10ee29ee1dad236ecbb9f0f7151b847d Mon Sep 17 00:00:00 2001
From: Vidar Holen <spam@vidarholen.net>
Date: Sat, 5 Apr 2014 16:29:35 -0700
Subject: [PATCH] Don't warn about expr when using <, > and friends
---
ShellCheck/Analytics.hs | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/ShellCheck/Analytics.hs b/ShellCheck/Analytics.hs
index 950c145..d59ed15 100644
--- a/ShellCheck/Analytics.hs
+++ b/ShellCheck/Analytics.hs
@@ -451,9 +451,14 @@ checkUuoc _ _ = return ()
prop_checkNeedlessCommands = verify checkNeedlessCommands "foo=$(expr 3 + 2)"
prop_checkNeedlessCommands2 = verify checkNeedlessCommands "foo=`echo \\`expr 3 + 2\\``"
prop_checkNeedlessCommands3 = verifyNot checkNeedlessCommands "foo=$(expr foo : regex)"
-checkNeedlessCommands _ cmd@(T_SimpleCommand id _ _) |
- cmd `isCommand` "expr" && (not $ ":" `elem` deadSimple cmd) =
+prop_checkNeedlessCommands4 = verifyNot checkNeedlessCommands "foo=$(expr foo \\< regex)"
+checkNeedlessCommands _ cmd@(T_SimpleCommand id _ args) |
+ cmd `isCommand` "expr" && (not $ any (`elem` words) exceptions) =
style id 2003 "expr is antiquated. Consider rewriting this using $((..)), ${} or [[ ]]."
+ where
+ -- These operators are hard to replicate in POSIX
+ exceptions = [ ":", "<", ">", "<=", ">=" ]
+ words = mapMaybe getLiteralString args
checkNeedlessCommands _ _ = return ()
prop_checkPipePitfalls3 = verify checkPipePitfalls "ls | grep -v mp3"