Unneeded disable directive

spec/ameba/inline_comments_spec.cr

@@ -83,5 +83,22 @@ module Ameba
       s.error(NamedRule.new, 3, 12, "")
       s.should_not be_valid
     end
+
+    it "does not disable if that is a commented out directive" do
+      s = Source.new %Q(
+        # # ameba:disable #{NamedRule.name}
+        Time.epoch(1483859302)
+      )
+      s.error(NamedRule.new, 3, 12, "")
+      s.should_not be_valid
+    end
+
+    it "does not disable if that is an inline commented out directive" do
+      s = Source.new %Q(
+        a = 1 # Disable it: # ameba:disable #{NamedRule.name}
+      )
+      s.error(NamedRule.new, 2, 12, "")
+      s.should_not be_valid
+    end
   end
 end

spec/ameba/rule/unneded_disable_directive_spec.cr

@@ -0,0 +1,80 @@
+require "../../spec_helper"
+
+module Ameba::Rule
+  describe UnneededDisableDirective do
+    subject = UnneededDisableDirective.new
+
+    it "passes if there are no comments" do
+      s = Source.new %(
+        a = 1
+      )
+      subject.catch(s).should be_valid
+    end
+
+    it "passes if there is disable directive" do
+      s = Source.new %(
+        a = 1 # my super var
+      )
+      subject.catch(s).should be_valid
+    end
+
+    it "passes if there is disable directive and it is needed" do
+      s = Source.new %Q(
+        a = 1 # ameba:disable #{NamedRule.name}
+      )
+      s.error NamedRule.new, 2, 1, "Alarm!", :disabled
+      subject.catch(s).should be_valid
+    end
+
+    it "ignores commented out disable directive" do
+      s = Source.new %Q(
+        # # ameba:disable #{NamedRule.name}
+        a = 1
+      )
+      s.error NamedRule.new, 3, 1, "Alarm!", :disabled
+      subject.catch(s).should be_valid
+    end
+
+    it "failes if there is unneeded directive" do
+      s = Source.new %Q(
+        # ameba:disable #{NamedRule.name}
+        a = 1
+      )
+      subject.catch(s).should_not be_valid
+      s.errors.first.message.should eq(
+        "Unnecessary disabling of #{NamedRule.name}"
+      )
+    end
+
+    it "fails if there is inline unneeded directive" do
+      s = Source.new %Q(a = 1 # ameba:disable #{NamedRule.name})
+      subject.catch(s).should_not be_valid
+      s.errors.first.message.should eq(
+        "Unnecessary disabling of #{NamedRule.name}"
+      )
+    end
+
+    it "detects mixed inline directives" do
+      s = Source.new %Q(
+        # ameba:disable Rule1, Rule2
+        a = 1 # ameba:disable Rule3
+      ), "source.cr"
+      subject.catch(s).should_not be_valid
+      s.errors.size.should eq 2
+      s.errors.first.message.should contain "Rule1, Rule2"
+      s.errors.last.message.should contain "Rule3"
+    end
+
+    it "reports error, location and message" do
+      s = Source.new %Q(
+        # ameba:disable Rule1, Rule2
+        a = 1
+      ), "source.cr"
+      subject.catch(s).should_not be_valid
+      error = s.errors.first
+      error.rule.should_not be_nil
+      error.location.to_s.should eq "source.cr:2:9"
+      error.message.should eq "Unnecessary disabling of Rule1, Rule2"
+    end
+  end
+end