Output a better error when pkg-config is not found - close #169

build_tests/configure/check_cfg_no_pkg_config.rb

@@ -0,0 +1,5 @@
+ENV["PATH"] = ""
+
+configure do
+  check_cfg package: "mypackage"
+end

lib/rscons/configure_op.rb

@@ -125,7 +125,12 @@ module Rscons
       elsif program = options[:program]
         Ansi.write($stdout, "Checking '", :cyan, program, :reset, "'... ")
       end
-      program ||= "pkg-config"
+      unless program
+        program = "pkg-config"
+        unless Util.find_executable(program)
+          raise RsconsError.new("Error: executable '#{program}' not found")
+        end
+      end
       args = options[:args] || %w[--cflags --libs]
       command = [program, *args, package].compact
       stdout, _, status = log_and_test_command(command)

spec/build_tests_spec.rb

@@ -2369,6 +2369,13 @@ EOF
           expect(result.stdout).to_not match /gcc.*-o.*myconfigtest1.*-DMYPACKAGE/
           expect(result.stdout).to match /gcc.*-o.*myconfigtest2.*-DMYPACKAGE/
         end
+
+        it "indicates that pkg-config command cannot be found" do
+          test_dir "configure"
+          result = run_rscons(args: %w[-f check_cfg_no_pkg_config.rb configure])
+          expect(result.stderr).to match /Error: executable 'pkg-config' not found/
+          expect(result.status).to_not eq 0
+        end
       end
 
       context "when passed a program" do