Run pathname specs from ruby/spec in CI and fix them

[eregon]

Includes the fixes from ruby/ruby#14303, although some of them are done slightly differently to match the semantics from pathname.c closer.

See #60 (comment) for the summary of what this PR does.

[eregon]

I also compared methods before and after #57:

diff methods_old.txt methods_new.txt 
50d49
< lutime
60a60
> path

path is expected new and is protected.
lutime is missing and the test was wrongly testing utime instead, will fix.

[eregon]

Ah and there is another bug in test/pathname/test_pathname.rb, its has_symlink? returns false, at least on Linux.

[eregon]

I rebased this on top of #61, there were many conflicts.
I copied the original PR to #62 for clarity as some commits became less clear due to the rebase.
Anyway I made sure the end result is similar, so the diff between this and #62 is:

diff --git a/lib/pathname.rb b/lib/pathname.rb
index 1c4ec6e..a0db812 100644
--- a/lib/pathname.rb
+++ b/lib/pathname.rb
@@ -210,6 +210,7 @@ require 'pathname.so' if RUBY_ENGINE == 'ruby'
 #
 class Pathname
 
+  # The version string.
   VERSION = "0.4.0"
 
   # :stopdoc:
@@ -338,14 +339,42 @@ class Pathname
   end
 
   if File.dirname('A:') == 'A:.' # DOSish drive letter
-    ABSOLUTE_PATH = /\A(?:[A-Za-z]:|#{SEPARATOR_PAT})/o
+    ABSOLUTE_PATH = /\A(?:[A-Za-z]:|#{SEPARATOR_PAT})/
   else
-    ABSOLUTE_PATH = /\A#{SEPARATOR_PAT}/o
+    ABSOLUTE_PATH = /\A#{SEPARATOR_PAT}/
   end
   private_constant :ABSOLUTE_PATH
 
   # :startdoc:
 
+  # Creates a full path, including any intermediate directories that don't yet
+  # exist.
+  #
+  # See FileUtils.mkpath and FileUtils.mkdir_p
+  def mkpath(mode: nil)
+    path = @path == '/' ? @path : @path.chomp('/')
+
+    stack = []
+    until File.directory?(path) || File.dirname(path) == path
+      stack.push path
+      path = File.dirname(path)
+    end
+
+    stack.reverse_each do |dir|
+      dir = dir == '/' ? dir : dir.chomp('/')
+      if mode
+        Dir.mkdir dir, mode
+        File.chmod mode, dir
+      else
+        Dir.mkdir dir
+      end
+    rescue SystemCallError
+      raise unless File.directory?(dir)
+    end
+
+    self
+  end
+
   # chop_basename(path) -> [pre-basename, basename] or nil
   def chop_basename(path) # :nodoc:
     base = File.basename(path)
@@ -1167,16 +1196,6 @@ end
 
 
 class Pathname    # * FileUtils *
-  # Creates a full path, including any intermediate directories that don't yet
-  # exist.
-  #
-  # See FileUtils.mkpath and FileUtils.mkdir_p
-  def mkpath(mode: nil)
-    require 'fileutils'
-    FileUtils.mkpath(@path, mode: mode)
-    self
-  end
-
   # Recursively deletes a directory, including all directories beneath it.
   #
   # See FileUtils.rm_rf

Which is expected changes upstreamed from ruby/ruby.

[byroot]

👍

[eregon]

I'll merge this, it fixes 3 major issues with testing in ruby/pathname:

• ruby/spec pathname specs were not run, but revealed issues in ruby/ruby in Migrate pathname.c to pathname_builtin.rb ruby#14303, now they are run here too.
• has_symlink? was always false which meant 8 tests did not run at all (!)
• the lutime test was skipped due to that has_symlink? bug, and was testing utime instead of lutime