[x/tour] add wc.Test function

X-Tour-Commit: 93e041dca7321db10205d07c691d6828bc9a8c2c

tour/wc/wc.go

@@ -81,6 +81,48 @@ func Serve(f func(string)map[string]int) {
 	log.Fatal(err)
 }
 
+// Test runs a test suite against f.
+func Test(f func(string)map[string]int) {
+	ok := true
+	for _, c := range testCases {
+		got := f(c.in)
+		if len(c.want) != len(got) {
+			ok = false
+		} else {
+			for k := range c.want {
+				if c.want[k] != got[k] {
+					ok = false
+				}
+			}
+		}
+		if !ok {
+			fmt.Printf("FAIL\n f(%q) =\n  %#v\n want:\n  %#v",
+				c.in, got, c.want)
+			break
+		}
+		fmt.Printf("PASS\n f(%q) = \n  %#v\n", c.in, got)
+	}
+}
+
+var testCases = []struct{
+	in string
+	want map[string]int
+}{
+	{"I am learning Go!", map[string]int{
+		"I": 1, "am": 1, "learning": 1, "Go!": 1,
+	}},
+	{"The quick brown fox jumped over the lazy dog.", map[string]int{
+		"The": 1, "quick": 1, "brown": 1, "fox": 1, "jumped": 1,
+		"over": 1, "the": 1, "lazy": 1, "dog.": 1,
+	}},
+	{"I ate a donut. Then I ate another donut.", map[string]int{
+		"I": 2, "ate": 2, "a": 1, "donut.": 2, "Then": 1, "another": 1,
+	}},
+	{"A man a plan a canal panama.", map[string]int{
+		"A": 1, "man": 1, "a": 2, "plan": 1, "canal": 1, "panama.": 1,
+	}},
+}
+
 var frontPage, table *template.Template
 
 func init() {