add :check_libpath option to check_lib configuration method - #107

build_tests/configure/check_lib_libpath1.rb

@@ -0,0 +1,5 @@
+build do
+  Environment.new(echo: :command) do |env|
+    env.Library("usr2/libfrobulous.a", "two.c")
+  end
+end

build_tests/configure/check_lib_libpath2.rb

@@ -0,0 +1,10 @@
+configure do
+  check_lib "m", check_libpath: ["./usr1"]
+  check_lib "frobulous", check_libpath: ["./usr2"]
+end
+
+build do
+  Environment.new(echo: :command) do |env|
+    env.Program("simple.exe", "simple.c")
+  end
+end

build_tests/configure/two.c

@@ -0,0 +1,4 @@
+int two(void)
+{
+    return 42;
+}

lib/rscons/configure_op.rb

@@ -235,6 +235,7 @@ module Rscons
 
     # Check for a library.
     def check_lib(lib, options = {})
+      check_libpath = [nil] + (options[:check_libpath] || [])
       Ansi.write($stdout, "Checking for library '", :cyan, lib, :reset, "'... ")
       File.open("#{@work_dir}/cfgtest.c", "wb") do |fh|
         fh.puts <<-EOF
@@ -249,8 +250,21 @@ module Rscons
         "_SOURCES" => "#{@work_dir}/cfgtest.c",
         "_TARGET" => "#{@work_dir}/cfgtest.exe",
       }
-      command = BasicEnvironment.new.build_command("${LDCMD}", vars)
+      status = 1
-      _, _, status = log_and_test_command(command)
+      check_libpath.each do |libpath|
+        env = BasicEnvironment.new
+        if libpath
+          env["LIBPATH"] += Array(libpath)
+        end
+        command = env.build_command("${LDCMD}", vars)
+        _, _, status = log_and_test_command(command)
+        if status == 0
+          if libpath
+            store_append({"LIBPATH" => Array(libpath)}, options)
+          end
+          break
+        end
+      end
       if status == 0
         store_append({"LIBS" => [lib]}, options)
       end

spec/build_tests_spec.rb

@@ -1986,6 +1986,23 @@ EOF
         expect(result.stdout).to match /Checking for library 'm'... found/
         expect(result.stdout).to_not match /-lm/
       end
+
+      it "modifies LIBPATH based on check_libpath" do
+        test_dir "configure"
+        FileUtils.mkdir_p("usr1")
+        FileUtils.mkdir_p("usr2")
+        result = run_rscons(rsconscript: "check_lib_libpath1.rb")
+        expect(result.stderr).to eq ""
+        expect(result.status).to eq 0
+        result = run_rscons(rsconscript: "check_lib_libpath2.rb", op: "configure")
+        expect(result.stderr).to eq ""
+        expect(result.status).to eq 0
+        result = run_rscons(rsconscript: "check_lib_libpath2.rb")
+        expect(result.stderr).to eq ""
+        expect(result.status).to eq 0
+        expect(result.stdout).to match %r{-L\./usr2}
+        expect(result.stdout).to_not match %r{-L\./usr1}
+      end
     end
 
     context "check_program" do