added example testing som UN*X commands

examples/CMDTEST_simple.rb

@@ -0,0 +1,102 @@
+#
+# Example of testing some UN*X commands.
+#
+
+class CMDTEST_simple < Cmdtest::Testcase
+
+  #----------------------------------------
+  # true
+
+  def test_true
+    cmd "true" do
+    end
+
+    # same but explicit
+    cmd "true" do
+      exit_zero
+      stdout_equal ""
+      stderr_equal ""
+    end
+
+    # same but explicit another way
+    cmd "true" do
+      exit_status 0
+      stdout_equal []
+      stderr_equal []
+    end
+  end
+
+  #----------------------------------------
+  # false
+
+  def test_false
+    cmd "false" do
+      exit_nonzero
+    end
+  end
+
+  #----------------------------------------
+  # sleep
+
+  def test_sleep
+    cmd "sleep 5" do
+      time 4..6
+    end
+  end
+
+  #----------------------------------------
+
+  def test_echo
+    cmd "echo" do
+      stdout_equal "\n"
+    end
+
+    cmd "echo hello" do
+      stdout_equal "hello\n"
+    end
+
+    cmd "echo hello world" do
+      stdout_equal "hello world\n"
+    end
+  end
+
+    #------------------------------
+
+    def test_touch
+      # one file
+      cmd "touch aaa" do
+        created_files "aaa"
+      end
+
+      # two files
+      cmd "touch bbb ccc" do
+        created_files "bbb", "ccc"
+      end
+
+      # existing file
+      cmd "touch aaa" do
+        changed_files "aaa"
+      end
+    end
+
+    #------------------------------
+
+    def test_mkdir
+      # one directory
+      cmd "mkdir aaa" do
+        created_files "aaa/"
+      end
+
+      # two directories
+      cmd "mkdir bbb ccc" do
+        created_files "bbb/", "ccc/"
+      end
+
+      # existing directory
+      cmd "mkdir aaa" do
+        exit_nonzero
+        stderr_equal /File exists/
+      end
+    end
+
+end