Fix: correctly detect that shard has no dependencies

closes crystal-lang#145

src/commands/check.cr

@@ -17,7 +17,7 @@ module Shards
       end
 
       private def has_dependencies?
-        spec.dependencies.any? || !Shards.production? || spec.development_dependencies.any?
+        spec.dependencies.any? || (!Shards.production? && spec.development_dependencies.any?)
       end
 
       private def verify(dependencies)

src/commands/list.cr

@@ -30,7 +30,7 @@ module Shards
 
       # FIXME: duplicates Check#has_dependencies?
       private def has_dependencies?
-        spec.dependencies.any? || !Shards.production? || spec.development_dependencies.any?
+        spec.dependencies.any? || (!Shards.production? && spec.development_dependencies.any?)
       end
     end
   end

test/integration/check_test.cr

@@ -30,6 +30,12 @@ class CheckCommandTest < Minitest::Test
     end
   end
 
+  def test_succeeds_without_dependencies_and_lockfile
+    with_shard({ name: "no_dependencies" }) do
+      run "shards check --no-color"
+    end
+  end
+
   def test_fails_when_dependencies_are_missing
     with_shard({ dependencies: { web: "*" } }) do
       run "shards install"