plugin/errors: 'consolidate' option (#2192)

- see more details at https://github.com/infobloxopen/coredns-plugin-errors/pull/3

plugin/errors/setup_test.go

@@ -10,24 +10,60 @@ func TestErrorsParse(t *testing.T) {
 	tests := []struct {
 		inputErrorsRules string
 		shouldErr        bool
+		optCount         int
 	}{
-		{`errors`, false},
-		{`errors stdout`, false},
-		{`errors errors.txt`, true},
-		{`errors visible`, true},
-		{`errors { log visible }`, true},
+		{`errors`, false, 0},
+		{`errors stdout`, false, 0},
+		{`errors errors.txt`, true, 0},
+		{`errors visible`, true, 0},
+		{`errors { log visible }`, true, 0},
 		{`errors
-		errors `, true},
-		{`errors a b`, true},
+		  errors `, true, 0},
+		{`errors a b`, true, 0},
+
+		{`errors {
+		    consolidate
+		  }`, true, 0},
+		{`errors {
+		    consolidate 1m
+		  }`, true, 0},
+		{`errors {
+		    consolidate 1m .* extra
+		  }`, true, 0},
+		{`errors {
+		    consolidate abc .*
+		  }`, true, 0},
+		{`errors {
+		    consolidate 1 .*
+		  }`, true, 0},
+		{`errors {
+		    consolidate 1m ())
+		  }`, true, 0},
+		{`errors {
+		    consolidate 1m ^exact$
+		  }`, false, 1},
+		{`errors {
+		    consolidate 1m error
+		  }`, false, 1},
+		{`errors {
+		    consolidate 1m "format error"
+		  }`, false, 1},
+		{`errors {
+		    consolidate 1m error1
+		    consolidate 5s error2
+		  }`, false, 2},
 	}
 	for i, test := range tests {
 		c := caddy.NewTestController("dns", test.inputErrorsRules)
-		_, err := errorsParse(c)
+		h, err := errorsParse(c)
 
 		if err == nil && test.shouldErr {
 			t.Errorf("Test %d didn't error, but it should have", i)
 		} else if err != nil && !test.shouldErr {
 			t.Errorf("Test %d errored, but it shouldn't have; got '%v'", i, err)
+		} else if h != nil && len(h.patterns) != test.optCount {
+			t.Errorf("Test %d: pattern count mismatch, expected %d, got %d",
+				i, test.optCount, len(h.patterns))
 		}
 	}
 }