[rubygems/rubygems] Don't fail when `uninstall --all` with default gem

Instead, display an informative message saying that uninstallation of
specific versions is being skipped because of being default gems.

https://github.com/rubygems/rubygems/commit/b44845aa1d

2 files changed, 49 insertions, 4 deletions

diff --git a/test/rubygems/test_gem_commands_uninstall_command.rb b/test/rubygems/test_gem_commands_uninstall_command.rb
index 4ac06977e3..927a241203 100644
--- a/test/rubygems/test_gem_commands_uninstall_command.rb
+++ b/test/rubygems/test_gem_commands_uninstall_command.rb
@@ -41,6 +41,51 @@ class TestGemCommandsUninstallCommand < Gem::InstallerTestCase
                  Gem::Specification.all_names.sort
   end
 
+  def test_execute_all_named_default_single
+    z_1 = new_default_spec 'z', '1'
+    install_default_gems z_1
+
+    assert_includes Gem::Specification.all_names, 'z-1'
+
+    @cmd.options[:all] = true
+    @cmd.options[:args] = %w[z]
+
+    use_ui @ui do
+      @cmd.execute
+    end
+
+    assert_equal %w[z-1], Gem::Specification.all_names.sort
+
+    output = @ui.output.split "\n"
+
+    assert_equal 'Gem z-1 cannot be uninstalled because it is a default gem', output.shift
+  end
+
+  def test_execute_all_named_default_multiple
+    z_1 = new_default_spec 'z', '1'
+    install_default_gems z_1
+
+    z_2, = util_gem 'z', 2
+    install_gem z_2
+
+    assert_includes Gem::Specification.all_names, 'z-1'
+    assert_includes Gem::Specification.all_names, 'z-2'
+
+    @cmd.options[:all] = true
+    @cmd.options[:args] = %w[z]
+
+    use_ui @ui do
+      @cmd.execute
+    end
+
+    assert_equal %w[z-1], Gem::Specification.all_names.sort
+
+    output = @ui.output.split "\n"
+
+    assert_equal 'Gem z-1 cannot be uninstalled because it is a default gem', output.shift
+    assert_equal 'Successfully uninstalled z-2', output.shift
+  end
+
   def test_execute_dependency_order
     initial_install
 
diff --git a/test/rubygems/test_gem_uninstaller.rb b/test/rubygems/test_gem_uninstaller.rb
index 9dfef7cfda..bf5ef5b4a2 100644
--- a/test/rubygems/test_gem_uninstaller.rb
+++ b/test/rubygems/test_gem_uninstaller.rb
@@ -221,13 +221,13 @@ class TestGemUninstaller < Gem::InstallerTestCase
 
     uninstaller = Gem::Uninstaller.new spec.name, :executables => true
 
-    e = assert_raises Gem::InstallError do
+    use_ui @ui do
       uninstaller.uninstall
     end
 
-    assert_equal 'gem "default" cannot be uninstalled ' +
-                 'because it is a default gem',
-                 e.message
+    lines = @ui.output.split("\n")
+
+    assert_equal 'Gem default-2 cannot be uninstalled because it is a default gem', lines.shift
   end
 
   def test_uninstall_default_gem_with_same_version