brew-audit - catch more interpolation style issues

1 files changed, 6 insertions, 1 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}"