Add 'which?' method

ChangeLog.md

@@ -2,7 +2,7 @@
 
 ## Next version
 
-*tbd*
+- Add `which?` utility method, that checks if a executable is available.
 
 ## Current and previous versions
 

build-cfg.yaml

@@ -7,6 +7,7 @@ sources:
   - exts/string
   - exts/hash
   - exts/pathname
+  - exts/mkmf
   - exts/thor
   - core/io
   - grammars/base_lexer

build/fizzy

@@ -55,6 +55,7 @@ require "shellwords"
 require "strscan"
 require "uri"
 require "yaml"
+require "mkmf"
 
 # Try to require `thor` or raise an exception.
 begin
@@ -174,6 +175,13 @@ class Pathname
 
 end
 
+# ☞ Exts → Mkmf ────────────────────────────────────────────────────────────────
+
+module MakeMakefile::Logging
+  # Turn off output on `mkmf` methods.
+  @quiet = true
+end
+
 # ☞ Exts → Thor ────────────────────────────────────────────────────────────────
 
 class Thor
@@ -633,6 +641,10 @@ module Fizzy::Environment
 
   include Fizzy::IO
 
+  def which?(name)
+    find_executable(name.to_s)
+  end
+
   # Return the environment variable matching the provided `name`.
   #
   def get_env(name, default: nil)

mkmf.log

@@ -0,0 +1,4 @@
+find_executable: checking for clang... -------------------- yes
+
+--------------------
+

src/core/environment.rb

@@ -4,6 +4,10 @@ module Fizzy::Environment
 
   include Fizzy::IO
 
+  def which?(name)
+    find_executable(name.to_s)
+  end
+
   # Return the environment variable matching the provided `name`.
   #
   def get_env(name, default: nil)

src/exts/mkmf.rb

@@ -0,0 +1,4 @@
+module MakeMakefile::Logging
+  # Turn off output on `mkmf` methods.
+  @quiet = true
+end

src/requires.rb

@@ -11,6 +11,7 @@
 require "strscan"
 require "uri"
 require "yaml"
+require "mkmf"
 
 # Try to require `thor` or raise an exception.
 begin