From ba98af142437a7d6f85736e3c94e7dd3ac5c101f Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Tue, 9 Jul 2019 22:00:50 -0400
Subject: [PATCH] default configure checks :fail option to false if :set_define
 is specified

---
 .../configure/check_c_header_no_fail_set_define.rb |  2 +-
 doc/user_guide.md                                  |  8 +++++++-
 lib/rscons/configure_op.rb                         | 14 +++++++++++---
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/build_tests/configure/check_c_header_no_fail_set_define.rb b/build_tests/configure/check_c_header_no_fail_set_define.rb
index 1ff17e3..79bb8ff 100644
--- a/build_tests/configure/check_c_header_no_fail_set_define.rb
+++ b/build_tests/configure/check_c_header_no_fail_set_define.rb
@@ -1,5 +1,5 @@
 configure do
-  check_c_header "not___found.h", fail: false, set_define: "HAVE_NOT___FOUND_H"
+  check_c_header "not___found.h", set_define: "HAVE_NOT___FOUND_H"
 end
 
 build do
diff --git a/doc/user_guide.md b/doc/user_guide.md
index 5e3cc3b..c712179 100644
--- a/doc/user_guide.md
+++ b/doc/user_guide.md
@@ -247,7 +247,7 @@ Example calls:
 
 ```ruby
 configure do
-  check_c_header "getopt.h", fail: false, set_define: "HAVE_GETOPT_H"
+  check_c_header "getopt.h", set_define: "HAVE_GETOPT_H"
   check_c_header "FreeType2.h"
   check_cxx_header "memory"
 end
@@ -259,6 +259,8 @@ end
 
 If the `:fail` option is set to `false`, then the absence of the header file
 will not result in the configure option failing.
+The `:fail` option defaults to `true` if the `:set_define` option is not
+defined, and defaults to `false` if the `:set_define` option is defined.
 
 ##### `:set_define`
 
@@ -302,6 +304,8 @@ end
 
 If the `:fail` option is set to `false`, then the absence of the library
 will not result in the configure option failing.
+The `:fail` option defaults to `true` if the `:set_define` option is not
+defined, and defaults to `false` if the `:set_define` option is defined.
 
 ##### `:set_define`
 
@@ -354,6 +358,8 @@ for configuration flags.
 
 If the `:fail` option is set to `false`, then the absence of the package or
 program requested will not result in the configure option failing.
+The `:fail` option defaults to `true` if the `:set_define` option is not
+defined, and defaults to `false` if the `:set_define` option is defined.
 
 ##### `:set_define`
 
diff --git a/lib/rscons/configure_op.rb b/lib/rscons/configure_op.rb
index 2bdbc50..0b5552c 100644
--- a/lib/rscons/configure_op.rb
+++ b/lib/rscons/configure_op.rb
@@ -411,6 +411,8 @@ module Rscons
     #   Common check options.
     # @option options [Boolean] :fail
     #   Whether to fail configuration if the requested item is not found.
+    #   This defaults to true if the :set_define option is not specified,
+    #   otherwise defaults to false if :set_define option is specified.
     # @option options [String] :set_define
     #   A define to set (in CPPDEFINES) if the requested item is found.
     # @option options [String] :success_message
@@ -423,11 +425,17 @@ module Rscons
           store_append("CPPDEFINES" => [options[:set_define]])
         end
       else
-        if options.has_key?(:fail) and not options[:fail]
-          Ansi.write($stdout, :yellow, "not found\n")
-        else
+        should_fail =
+          if options.has_key?(:fail)
+            options[:fail]
+          else
+            !options[:set_define]
+          end
+        if should_fail
           Ansi.write($stdout, :red, "not found\n")
           raise ConfigureFailure.new
+        else
+          Ansi.write($stdout, :yellow, "not found\n")
         end
       end
     end