Add predicates for platforms

Merged: https://github.com/ruby/ruby/pull/11583

test/ruby/test_process.rb

@@ -1874,7 +1874,7 @@ class TestProcess < Test::Unit::TestCase
     end
 
     def test_daemon_noclose
-      pend "macOS 15 beta is not working with this test" if /darwin/ =~ RUBY_PLATFORM && /15/ =~ `sw_vers -productVersion`
+      pend "macOS 15 beta is not working with this test" if macos?(15)
 
       data = IO.popen("-", "r+") do |f|
         break f.read if f

test/ruby/test_rubyoptions.rb

@@ -876,7 +876,7 @@ class TestRubyOptions < Test::Unit::TestCase
   end
 
   def assert_segv(args, message=nil, list: SEGVTest::ExpectedStderrList, **opt, &block)
-    pend "macOS 15 beta is not working with this assertion" if /darwin/ =~ RUBY_PLATFORM && /15/ =~ `sw_vers -productVersion`
+    pend "macOS 15 beta is not working with this assertion" if macos?(15)
 
     # We want YJIT to be enabled in the subprocess if it's enabled for us
     # so that the Ruby description matches.
@@ -921,7 +921,7 @@ class TestRubyOptions < Test::Unit::TestCase
   end
 
   def assert_crash_report(path, cmd = nil, &block)
-    pend "macOS 15 beta is not working with this assertion" if /darwin/ =~ RUBY_PLATFORM && /15/ =~ `sw_vers -productVersion`
+    pend "macOS 15 beta is not working with this assertion" if macos?(15)
 
     Dir.mktmpdir("ruby_crash_report") do |dir|
       list = SEGVTest::ExpectedStderrList

test/ruby/test_vm_dump.rb

@@ -5,7 +5,7 @@ return unless /darwin/ =~ RUBY_PLATFORM
 
 class TestVMDump < Test::Unit::TestCase
   def assert_darwin_vm_dump_works(args, timeout=nil)
-    pend "macOS 15 beta is not working with this assertion" if /darwin/ =~ RUBY_PLATFORM && /15/ =~ `sw_vers -productVersion`
+    pend "macOS 15 beta is not working with this assertion" if macos?(15)
 
     assert_in_out_err(args, "", [], /^\[IMPORTANT\]/, timeout: timeout || 300)
   end

tool/lib/core_assertions.rb

@@ -861,6 +861,65 @@ eom
         token = "\e[7;1m#{$$.to_s}:#{Time.now.strftime('%s.%L')}:#{rand(0x10000).to_s(16)}:\e[m"
         return token.dump, Regexp.quote(token)
       end
+
+      # Platform predicates
+
+      def self.mswin?
+        defined?(@mswin) ? @mswin : @mswin = RUBY_PLATFORM.include?('mswin')
+      end
+      private def mswin?
+        CoreAssertions.mswin?
+      end
+
+      def self.mingw?
+        defined?(@mingw) ? @mingw : @mingw = RUBY_PLATFORM.include?('mingw')
+      end
+      private def mingw?
+        CoreAssertions.mingw?
+      end
+
+      module_function def windows?
+        mswin? or mingw?
+      end
+
+      def self.compare_version(a, b)
+        b.empty? ? true && a : a && (a <=> b) >= 0
+      end
+
+      def self.linux?(*ver)
+        unless defined?(@linux)
+          @linux = RUBY_PLATFORM.include?('linux') && `uname -r`.scan(/\d+/).map(&:to_i)
+        end
+        compare_version @linux, ver
+      end
+      private def linux?(*ver)
+        CoreAssertions.linux?(*ver)
+      end
+
+      def self.glibc?(*ver)
+        unless defined?(@glibc)
+          libc = `/usr/bin/ldd /bin/sh`[/^\s*libc.*=> *\K\S*/]
+          if libc and /version (\d+)\.(\d+)\.$/ =~ IO.popen([libc], &:read)[]
+            @glibc = [$1.to_i, $2.to_i]
+          else
+            @glibc = false
+          end
+        end
+        compare_version @glibc, ver
+      end
+      private def glibc?(*ver)
+        CoreAssertions.glibc?(*ver)
+      end
+
+      def self.macos?(*ver)
+        unless defined?(@macos)
+          @macos = RUBY_PLATFORM.include?('darwin') && `sw_vers -productVersion`.scan(/\d+/).map(&:to_i)
+        end
+        compare_version @macos, ver
+      end
+      private def macos?(*ver)
+        CoreAssertions.macos?(*ver)
+      end
     end
   end
 end

tool/lib/test/unit.rb

@@ -1893,6 +1893,7 @@ module Test
         @backtrace = ex.backtrace
       end
 
+
       attr_accessor :message, :backtrace
     end
   end