Add dry-run to config

src/spectator/command_line_arguments_config_source.cr

@@ -16,6 +16,7 @@ module Spectator
         parser.on("-v", "--verbose", "Verbose output using document formatter") { builder.formatter = Formatting::DocumentFormatter.new }
         parser.on("-f", "--fail-fast", "Stop testing on first failure") { builder.fail_fast }
         parser.on("-b", "--fail-blank", "Fail if there are no examples") { builder.fail_blank }
+        parser.on("-d", "--dry-run", "Don't run any tests, output what would have run") { builder.dry_run }
         parser.on("-h", "--help", "Show this help") { puts parser; exit }
         parser.on("-e", "--example STRING", "Run examples whose full nested names include STRING") { |pattern| raise NotImplementedError.new("-e") }
         parser.on("-l", "--line LINE", "Run examples whose line matches LINE") { |line| raise NotImplementedError.new("-l") }

src/spectator/config.cr

@@ -10,11 +10,16 @@ module Spectator
     # Indicates whether the test should fail if there are no examples.
     getter? fail_blank : Bool
 
+    # Indicates whether the test should be done as a dry-run.
+    # Examples won't run, but the output will show that they did.
+    getter? dry_run : Bool
+
     # Creates a new configuration.
     def initialize(builder)
       @formatter = builder.formatter
       @fail_fast = builder.fail_fast?
       @fail_blank = builder.fail_blank?
+      @dry_run = builder.dry_run?
     end
   end
 end

src/spectator/config_builder.cr

@@ -11,6 +11,7 @@ module Spectator
     @formatter : Formatting::Formatter? = nil
     @fail_fast = false
     @fail_blank = false
+    @dry_run = false
 
     # Sets the formatter to use for reporting test progress and results.
     def formatter=(formatter : Formatting::Formatter)
@@ -50,7 +51,7 @@ module Spectator
       self.fail_blank = true
     end
 
-    # Sets teh fail-blank mode.
+    # Enables or disables fail-blank mode.
     def fail_blank=(flag)
       @fail_blank = flag
     end
@@ -61,6 +62,22 @@ module Spectator
       @fail_blank
     end
 
+    # Enables dry-run mode.
+    def dry_run
+      self.dry_run = true
+    end
+
+    # Enables or disables dry-run mode.
+    def dry_run=(flag)
+      @dry_run = flag
+    end
+
+    # Indicates whether dry-run mode is enabled.
+    # In this mode, no tests are run, but output acts like they were.
+    def dry_run?
+      @dry_run
+    end
+
     # Creates a configuration.
     def build : Config
       Config.new(self)