New rule: variable names

spec/ameba/rules/variable_names_spec.cr

@@ -0,0 +1,61 @@
+require "../../spec_helper"
+
+module Ameba
+  subject = Rules::VariableNames.new
+
+  private def it_reports_var_name(content, expected)
+    it "reports method name #{expected}" do
+      s = Source.new content
+      Rules::VariableNames.new.catch(s).should_not be_valid
+      s.errors.first.message.should contain expected
+    end
+  end
+
+  describe Rules::VariableNames do
+    it "passes if var names are underscore-cased" do
+      s = Source.new %(
+        class Greeting
+          @@default_greeting = "Hello world"
+
+          def initialize(@custom_greeting = nil)
+          end
+
+          def print_greeting
+            greeting = @custom_greeting || @@default_greeting
+            puts greeting
+          end
+        end
+      )
+      subject.catch(s).should be_valid
+    end
+
+    it_reports_var_name %(myBadNamedVar = 1), "my_bad_named_var"
+    it_reports_var_name %(wrong_Name = 'y'), "wrong_name"
+
+    it_reports_var_name %(
+      class Greeting
+        def initialize(@badNamed = nil)
+        end
+      end
+    ), "bad_named"
+
+    it_reports_var_name %(
+      class Greeting
+        @@defaultGreeting = "Hello world"
+      end
+    ), "default_greeting"
+
+    it "reports rule, pos and message" do
+      s = Source.new %(
+        badName = "Yeah"
+      )
+      subject.catch(s).should_not be_valid
+      error = s.errors.first
+      error.rule.should_not be_nil
+      error.pos.should eq 2
+      error.message.should eq(
+        "Var name should be underscore-cased: bad_name, not badName"
+      )
+    end
+  end
+end