Fix run of only one selected test

lib/retest/runner.rb

@@ -29,21 +29,17 @@ def run_all
     end
 
     def format_instruction(changed_files: [], test_files: [])
-      if test_files.size >=2
+      if changed_files.size == 0 && test_files.size >= 1
         instruction = command.clone(all: false).to_s
         tests_string = command.format_batch(*test_files)
         log("Tests selected:")
         test_files.each { |test_file| log("  - #{test_file}") }
-
-        instruction.gsub!('<test>', tests_string)
-      else
-        instruction = command.to_s
-        instruction = format_changed_files(instruction: instruction, files: changed_files)
-        instruction = format_test_files(instruction: instruction, files: test_files)
+        return instruction.gsub('<test>', tests_string)
       end
 
-      log("\n")
-      instruction
+      instruction = command.to_s
+      instruction = format_changed_files(instruction: instruction, files: changed_files)
+      instruction = format_test_files(instruction: instruction, files: test_files)
     end
 
     def format_test_files(instruction:, files:)
@@ -84,6 +80,7 @@ def print_test_file_not_found
     end
 
     def system_run(command)
+      log("\n")
       result = system(command) ? :tests_pass : :tests_fail
       changed
       notify_observers(result)