1 files changed, 48 insertions, 8 deletions
diff --git a/spec/ruby/language/safe_spec.rb b/spec/ruby/language/safe_spec.rb
index 305965c1a7..9b8350c892 100644
--- a/spec/ruby/language/safe_spec.rb
+++ b/spec/ruby/language/safe_spec.rb
@@ -41,20 +41,30 @@ describe "The $SAFE variable" do
 
   ruby_version_is ""..."2.6" do
     it "cannot be set to values below 0" do
-        lambda {
-          proc {
-            $SAFE = -100
-          }.call
-        }.should raise_error(SecurityError, /tried to downgrade safe level from 0 to -100/)
+      lambda {
+        proc {
+          $SAFE = -100
+        }.call
+      }.should raise_error(SecurityError, /tried to downgrade safe level from 0 to -100/)
     end
   end
 
-  it "cannot be set to values above 4" do
+  ruby_version_is "2.6" do
+    it "raises ArgumentError when set to values below 0" do
       lambda {
         proc {
-          $SAFE = 100
+          $SAFE = -100
         }.call
-      }.should raise_error(ArgumentError, /\$SAFE=2 to 4 are obsolete/)
+      }.should raise_error(ArgumentError, "$SAFE should be >= 0")
+    end
+  end
+
+  it "cannot be set to values above 4" do
+    lambda {
+      proc {
+        $SAFE = 100
+      }.call
+    }.should raise_error(ArgumentError, /\$SAFE=2 to 4 are obsolete/)
   end
 
   ruby_version_is ""..."2.6" do
@@ -84,6 +94,36 @@ describe "The $SAFE variable" do
     end
   end
 
+  ruby_version_is "2.6" do
+    it "can be manually lowered" do
+      $SAFE = 1
+      $SAFE = 0
+      $SAFE.should == 0
+    end
+
+    it "is not Proc local" do
+      $SAFE.should == 0
+      proc {
+        $SAFE = 1
+      }.call
+      $SAFE.should == 1
+    end
+
+    it "is not lambda local" do
+      $SAFE.should == 0
+      lambda {
+        $SAFE = 1
+      }.call
+      $SAFE.should == 1
+    end
+
+    it "is global like regular global variables" do
+      Thread.new { $SAFE }.value.should == 0
+      $SAFE = 1
+      Thread.new { $SAFE }.value.should == 1
+    end
+  end
+
   it "can be read when default from Thread#safe_level" do
     Thread.current.safe_level.should == 0
   end