Test coverage increases

app/lib/celery_script/checker.rb

@@ -39,6 +39,16 @@ module CeleryScript
       e
     end
 
+    def check_leaf(node)
+      allowed  = corpus.values(node)
+      actual   = node.value.class
+      ok_leaf  = allowed.include?(actual)
+      raise TypeCheckError, (BAD_LEAF % [ node.kind,
+                                          node.parent.kind,
+                                          allowed.inspect,
+                                          actual.inspect]) unless ok_leaf
+    end
+
     private
 
     def validate(node)
@@ -134,17 +144,6 @@ module CeleryScript
       raise TypeCheckError, (BAD_BODY % [prnt.kind, child.kind, ok.inspect])
     end
 
-    def check_leaf(node)
-      allowed = corpus.values(node)
-      actual = node.value.class
-      unless allowed.include?(actual)
-        raise TypeCheckError, (BAD_LEAF % [ node.kind,
-                                            node.parent.kind,
-                                            allowed.inspect,
-                                            actual.inspect])
-      end
-    end
-
     def malformed_node!(expectation)
       raise TypeCheckError, (MALFORMED % expectation)
     end

spec/lib/celery_script/checker_spec.rb

@@ -61,6 +61,14 @@ describe CeleryScript::Checker do
     hash[:body][0][:args][:location][:args][:x] = "supposed to be an Integer"
     result = checker.run
     expect(result.message).to eq("Expected leaf 'x' within 'coordinate' to"\
-                                 " be one of: [Integer] but got String")
+                                  " be one of: [Integer] but got String")
+  end
+
+  it "finds a bad leaf" do
+    parent = CeleryScript::AstNode.new(parent = nil, args: {}, kind: "nothing")
+    expect {
+      checker.check_leaf CeleryScript::AstLeaf.new(parent, 6, :location)
+    }.to raise_error(CeleryScript::TypeCheckError)
+
   end
 end