From f89f49df44d2d04eac338ead2d0843304414889e Mon Sep 17 00:00:00 2001
From: Simon Ruderich <simon@ruderich.org>
Date: Sun, 7 Mar 2010 21:49:57 +0100
Subject: [PATCH] lib.sh: Improve installed() to work with more which.

Also add tests to check for different which implementations.
---
 lib.sh                |  2 +-
 tests/lib.sh.test     | 32 ++++++++++++++++++++++++++------
 tests/lib.sh.test.out |  6 ++++--
 3 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/lib.sh b/lib.sh
index da00cce..49ce998 100644
--- a/lib.sh
+++ b/lib.sh
@@ -11,7 +11,7 @@ unset LS_COLORS
 # Check if the given program is installed. Returns 0 if it exists, 1
 # otherwise; so it can be used in if.
 installed() {
-    which $1 | grep -E '^/' > /dev/null
+    which $1 2>&1 | perl -ne 'if (not m{^/}) { exit 1 }'
 }
 
 # Prints the current OS. Supported are Debian (debian), Gentoo (gentoo) and
diff --git a/tests/lib.sh.test b/tests/lib.sh.test
index 32bbd70..171c7c2 100644
--- a/tests/lib.sh.test
+++ b/tests/lib.sh.test
@@ -3,21 +3,41 @@
 
 . ../lib.sh
 
-# Tests for installed() with hopefully proper exit codes (1 if the program was
-# not found).
+# which with proper exit codes and output to stdout.
+which() {
+    if [ $1 = ls ]; then
+        echo /bin/ls
+    else
+        echo no doesnt-exist in /usr/bin /bin /usr/sbin /sbin
+        (exit 1)
+    fi
+}
+echo stdout which
+installed ls && echo ls installed
+installed doesnt-exist && echo doesnt-exist installed
+
+# which with proper exit codes and output to stderr in case of an error.
+which() {
+    if [ $1 = ls ]; then
+        echo /bin/ls
+    else
+        echo no doesnt-exist in /usr/bin /bin /usr/sbin /sbin >&2
+        (exit 1)
+    fi
+}
+echo stderr which
 installed ls && echo ls installed
 installed doesnt-exist && echo doesnt-exist installed
 
-# Simulate BSD `which` like on Mac OS X which doesn't use exit codes.
-function which() {
-    echo Mac OS X which for $1 >&2
+# which with no proper exit codes and output to stdout in case of an error.
+which() {
     if [ $1 = ls ]; then
         echo /bin/ls
     else
         echo no doesnt-exist in /usr/bin /bin /usr/sbin /sbin
     fi
 }
-# Tests for installed() without exit codes.
+echo stupid which
 installed ls && echo ls installed
 installed doesnt-exist && echo doesnt-exist installed
 
diff --git a/tests/lib.sh.test.out b/tests/lib.sh.test.out
index 9258e0f..7139144 100644
--- a/tests/lib.sh.test.out
+++ b/tests/lib.sh.test.out
@@ -1,7 +1,9 @@
+stdout which
 ls installed
-Mac OS X which for ls
+stderr which
+ls installed
+stupid which
 ls installed
-Mac OS X which for doesnt-exist
 m4: generating 'tmp/test' from 'tmp/test.m4' with options '-DTEST=m4'
 ###################################
 # WARNING! DO NOT EDIT THIS FILE! #
-- 
2.43.2