10 files changed, 19 insertions, 12 deletions
diff --git a/Library/Contributions/examples/brew-audit.rb b/Library/Contributions/examples/brew-audit.rb
index 666d52423..b9c36e00b 100755
--- a/Library/Contributions/examples/brew-audit.rb
+++ b/Library/Contributions/examples/brew-audit.rb
@@ -19,7 +19,7 @@ def audit_formula_text text
     problems << " * Remove 'use_mirror' from url."
   end
 
-  # 2 (or more, if in an if block) spaces before depends_on, please
+  # 2 (or more in an if block) spaces before depends_on, please
   if text =~ /^\ ?depends_on/
     problems << " * Check indentation of 'depends_on'."
   end
@@ -29,6 +29,11 @@ def audit_formula_text text
     problems << " * Don't need 'FileUtils.' before #{$1}."
   end
 
+  # Check for string interpolation of single values.
+  if text =~ /(system|inreplace|gsub!|change_make_var!) .* ['"]#\{(\w+)\}['"]/
+    problems << " * Don't need to interpolate \"#{$2}\" with #{$1}"
+  end
+
   # Check for string concatenation; prefer interpolation
   if text =~ /(#\{\w+\s*\+\s*['"][^}]+\})/
     problems << " * Try not to concatenate paths in string interpolation:\n   #{$1}"
diff --git a/Library/Formula/cdb.rb b/Library/Formula/cdb.rb
index 9bb34509f..0382608bf 100644
--- a/Library/Formula/cdb.rb
+++ b/Library/Formula/cdb.rb
@@ -6,7 +6,7 @@ class Cdb <Formula
   md5 '81fed54d0bde51b147dd6c20cdb92d51'
 
   def install
-    inreplace "conf-home", "/usr/local", "#{prefix}"
+    inreplace "conf-home", "/usr/local", prefix
     system "make setup"
   end
 end
diff --git a/Library/Formula/falcon.rb b/Library/Formula/falcon.rb
index 50dc69cdf..1518efcdf 100644
--- a/Library/Formula/falcon.rb
+++ b/Library/Formula/falcon.rb
@@ -24,7 +24,7 @@ class Falcon <Formula
   def install
     cmake_opts = "-DCMAKE_INSTALL_NAME_DIR=#{lib}"
     ENV.append "EXTRA_CMAKE", cmake_opts
-    system "./build.sh", "-p", "#{prefix}", "-int", "-el"
+    system "./build.sh", "-p", prefix, "-int", "-el"
     system "./build.sh", "-i"
     # install the htmldocs for the core and standard modules (feathers)
     FalconHtmldocs.new.brew { (doc+'core-doc').install Dir['*'] }
diff --git a/Library/Formula/ioke.rb b/Library/Formula/ioke.rb
index 44e749ccf..a89467086 100644
--- a/Library/Formula/ioke.rb
+++ b/Library/Formula/ioke.rb
@@ -11,7 +11,7 @@ class Ioke <Formula
 
     # Point IOKE_HOME to libexec
     inreplace 'bin/ioke' do |s|
-      s.change_make_var! 'IOKE_HOME', "#{libexec}"
+      s.change_make_var! 'IOKE_HOME', libexec
     end
 
     # Install jars in libexec to avoid conflicts
diff --git a/Library/Formula/kiwi.rb b/Library/Formula/kiwi.rb
index a7912ba3a..70cad6d6c 100644
--- a/Library/Formula/kiwi.rb
+++ b/Library/Formula/kiwi.rb
@@ -8,7 +8,7 @@ class Kiwi <Formula
   depends_on 'rlwrap' => :recommended
 
   def install
-    inreplace "Makefile", "/usr/local", "#{prefix}"
+    inreplace "Makefile", "/usr/local", prefix
     system "make install"
   end
 
diff --git a/Library/Formula/liboil.rb b/Library/Formula/liboil.rb
index 8c31e5ccf..798548238 100644
--- a/Library/Formula/liboil.rb
+++ b/Library/Formula/liboil.rb
@@ -10,7 +10,7 @@ class Liboil <Formula
 
   def install
     arch = Hardware.is_64_bit? ? 'x64_64' : 'i386'
-    inreplace "configure", "__HOST_CPU__", "#{arch}"
+    inreplace "configure", "__HOST_CPU__", arch
     system "./configure", "--prefix=#{prefix}", "--disable-dependency-tracking"
     system "make"
     system "make install"
diff --git a/Library/Formula/nu.rb b/Library/Formula/nu.rb
index 4893d2af3..a5182beb4 100644
--- a/Library/Formula/nu.rb
+++ b/Library/Formula/nu.rb
@@ -8,11 +8,13 @@ class Nu <Formula
   depends_on 'pcre'
 
   def install
-    ENV['PREFIX']="#{prefix}"
+    ENV['PREFIX'] = prefix
+
     inreplace "Makefile" do |s|
       cflags = s.get_make_var "CFLAGS"
       s.change_make_var! "CFLAGS", "#{cflags} #{ENV["CPPFLAGS"]}"
     end
+
     inreplace "Nukefile" do |s|
       case Hardware.cpu_type
       when :intel
diff --git a/Library/Formula/rabbitmq.rb b/Library/Formula/rabbitmq.rb
index 461ea14be..68e5720c7 100644
--- a/Library/Formula/rabbitmq.rb
+++ b/Library/Formula/rabbitmq.rb
@@ -35,7 +35,7 @@ class Rabbitmq <Formula
 
     # RabbitMQ Erlang binaries are installed in lib/rabbitmq/erlang/lib/rabbitmq-x.y.z/ebin
     # therefore need to add this path for erl -pa
-    inreplace sbin+'rabbitmq-env', '${SCRIPT_DIR}/..', "#{target_dir}"
+    inreplace sbin+'rabbitmq-env', '${SCRIPT_DIR}/..', target_dir
   end
 end
 
diff --git a/Library/Formula/rubinius.rb b/Library/Formula/rubinius.rb
index 457a4d76a..fae7732e2 100644
--- a/Library/Formula/rubinius.rb
+++ b/Library/Formula/rubinius.rb
@@ -14,11 +14,11 @@ class Rubinius < Formula
     # Let Rubinius define its own flags; messing with these causes build breaks.
     %w{CC CXX LD CFLAGS CXXFLAGS CPPFLAGS LDFLAGS}.each { |e| ENV.delete(e) }
 
-    ENV['RELEASE'] = "#{version}" # to fix issues with "path already exists"
+    ENV['RELEASE'] = version # to fix issues with "path already exists"
 
     # "--skip-system" means to use the included LLVM
     system "./configure", "--skip-system",
-                          "--prefix", "#{prefix}",
+                          "--prefix", prefix,
                           "--includedir", "#{include}/rubinius",
                           "--libdir", lib,
                           "--mandir", man, # For completeness; no manpages exist yet.
diff --git a/Library/Formula/tinyproxy.rb b/Library/Formula/tinyproxy.rb
index 57011b264..2d60dfe05 100644
--- a/Library/Formula/tinyproxy.rb
+++ b/Library/Formula/tinyproxy.rb
@@ -9,8 +9,8 @@ class Tinyproxy <Formula
 
   def install
     inreplace 'doc/tinyproxy.conf' do |s|
-      s.gsub! '/var', "#{var}"
-      s.gsub! '/usr/share', "#{share}"
+      s.gsub! '/var', var
+      s.gsub! '/usr/share', share
     end
 
     system "./configure", "--prefix=#{prefix}", "--disable-debug", "--disable-dependency-tracking"