Fix version parsing (#605)

Signed-off-by: James Couball <jcouball@yahoo.com>

lib/git/lib.rb

@@ -63,8 +63,6 @@ def initialize(base = nil, logger = nil)
         @git_work_dir = base[:working_directory]
       end
       @logger = logger
-
-      Git::Lib.warn_if_old_command(self)
     end
 
     # creates or reinitializes the repository
@@ -1029,8 +1027,9 @@ def archive(sha, file = nil, opts = {})
     # returns the current version of git, as an Array of Fixnums.
     def current_command_version
       output = command('version')
-      version = output[/\d+\.\d+(\.\d+)+/]
-      version.split('.').collect {|i| i.to_i}
+      version = output[/\d+(\.\d+)+/]
+      version_parts = version.split('.').collect { |i| i.to_i }
+      version_parts.fill(0, version_parts.length...3)
     end
 
     def required_command_version
@@ -1043,10 +1042,11 @@ def meets_required_version?
 
     def self.warn_if_old_command(lib)
       return true if @version_checked
+      @version_checked = true
       unless lib.meets_required_version?
         $stderr.puts "[WARNING] The git gem requires git #{lib.required_command_version.join('.')} or later, but only found #{lib.current_command_version.join('.')}. You should probably upgrade."
       end
-      @version_checked = true
+      true
     end
 
     private
@@ -1104,6 +1104,8 @@ def with_custom_env_variables(&block)
     end
 
     def command(cmd, *opts, &block)
+      Git::Lib.warn_if_old_command(self)
+
       command_opts = { chomp: true, redirect: '' }
       if opts.last.is_a?(Hash)
         command_opts.merge!(opts.pop)

tests/units/test_lib_meets_required_version.rb

@@ -21,4 +21,31 @@ def test_with_old_command_version
     lib.define_singleton_method(:current_command_version) { [major_version, minor_version] }
     assert !lib.meets_required_version?
   end
+
+  def test_parse_version
+    lib = Git::Lib.new(nil, nil)
+
+    versions_to_test = [
+      { version_string: 'git version 2.1', expected_result: [2, 1, 0] },
+      { version_string: 'git version 2.28.4', expected_result: [2, 28, 4] },
+      { version_string: 'git version 2.32.GIT', expected_result: [2, 32, 0] },
+    ]
+
+    lib.instance_variable_set(:@next_version_index, 0)
+
+    lib.define_singleton_method(:command) do |cmd, *opts, &block|
+      raise ArgumentError unless cmd == 'version'
+      versions_to_test[@next_version_index][:version_string].tap { @next_version_index += 1 }
+    end
+
+    lib.define_singleton_method(:next_version_index) { @next_version_index }
+
+    expected_version = versions_to_test[lib.next_version_index][:expected_result]
+    actual_version = lib.current_command_version
+    assert_equal(expected_version, actual_version)
+
+    expected_version = versions_to_test[lib.next_version_index][:expected_result]
+    actual_version = lib.current_command_version
+    assert_equal(expected_version, actual_version)
+  end
 end