Port Card Number and Pangram to test{}

This required a small tweak to outputTests() which I think is valid, we
skip over any empty strings in expected output. This allows these two
holes to have arguments that produce no output. I don't think any
current holes support empty string as an expected output for an arg.

The stutter in Card Number of repeating the valid hardcoded test cases
is a little unforunate but it's better than having yet another struct we
turn into test{}. Maybe it points to having a simple builder func that
takes an arg and a bool.

We now unconditionally print the arg separator in outputTests() which is
fine since we merged code-golf#1333 which unconditionally strips trailing
whitespace from every hole's expected output.

hole/card-number-validation.go

@@ -1,16 +1,8 @@
 package hole
 
-import (
-	"strconv"
-	"strings"
-)
+import "strconv"
 
 func cardNumberValidation() []Run {
-	type Case struct {
-		arg   string
-		valid bool
-	}
-
 	digitSum := func(n int) int {
 		return n - n/10*9
 	}
@@ -34,13 +26,13 @@ func cardNumberValidation() []Run {
 		return result
 	}
 
-	cases := []Case{
-		{"4242 4242 4242 4242", true},
-		{"4242 4244 4242 4242", false},
-		{"5555 5555 5555 4444", true},
-		{"5555 5555 5555 5444", false},
-		{"3566 0020 2036 0505", true},
-		{"3656 0020 2036 0505", false},
+	tests := []test{
+		{"4242 4242 4242 4242", "4242 4242 4242 4242"},
+		{"4242 4244 4242 4242", ""},
+		{"5555 5555 5555 4444", "5555 5555 5555 4444"},
+		{"5555 5555 5555 5444", ""},
+		{"3566 0020 2036 0505", "3566 0020 2036 0505"},
+		{"3656 0020 2036 0505", ""},
 	}
 
 	for i := range 100 {
@@ -53,23 +45,15 @@ func cardNumberValidation() []Run {
 		if i < 50 {
 			lastDigit = randInt(0, 9)
 		}
-		cases = append(cases, Case{formatDigits(append(digits, lastDigit)), lastDigit == checkDigit})
-	}
-
-	shuffle(cases)
-	args := make([]string, len(cases))
-	var answer strings.Builder
 
-	for i, c := range cases {
-		args[i] = c.arg
-
-		if c.valid {
-			if answer.Len() > 0 {
-				answer.WriteByte('\n')
-			}
-			answer.WriteString(c.arg)
+		cardNumber := formatDigits(append(digits, lastDigit))
+		t := test{in: cardNumber}
+		if lastDigit == checkDigit {
+			t.out = cardNumber
 		}
+
+		tests = append(tests, t)
 	}
 
-	return []Run{{Args: args, Answer: answer.String()}}
+	return outputTests(shuffle(tests))
 }

hole/hole.go

@@ -83,10 +83,10 @@ func outputTestsWithSep(sep string, testRuns ...[]test) []Run {
 		for i, t := range tests {
 			args[i] = t.in
 
-			if i > 0 {
+			if t.out != "" {
+				answer.WriteString(t.out)
 				answer.WriteString(sep)
 			}
-			answer.WriteString(t.out)
 		}
 
 		runs[i] = Run{Args: args, Answer: answer.String()}

hole/pangram-grep.go

@@ -7,13 +7,13 @@ import (
 )
 
 func pangramGrep() []Run {
-	return []Run{
+	return outputTests(
 		pangramGrepTests(2, 5),
 		pangramGrepTests(0, 0),
-	}
+	)
 }
 
-func pangramGrepTests(l, r int) Run {
+func pangramGrepTests(l, r int) []test {
 	// They all start lowercase and valid.
 	pangrams := shuffle([][]byte{
 		[]byte("6>_4\"gv9lb?2!ic7}=-m'fd30ph].o%@w+[8unk&t1es<az(x;${^y#)q,rj\\5/*:"),
@@ -102,25 +102,21 @@ func pangramGrepTests(l, r int) Run {
 		}
 	}
 
-	var args []string
-	var out string
+	tests := make([]test, len(pangrams))
 
 outer:
-	for _, pangram := range shuffle(pangrams) {
+	for i, pangram := range shuffle(pangrams) {
 		str := string(pangram)
-		args = append(args, str)
+		tests[i].in = str
 
 		for c := 'a'; c <= 'z'; c++ {
 			if !strings.ContainsRune(str, c) && !strings.ContainsRune(str, c-32) {
 				continue outer
 			}
 		}
 
-		out += str + "\n"
+		tests[i].out = str
 	}
 
-	// Drop the trailing newline.
-	out = out[:len(out)-1]
-
-	return Run{Args: args, Answer: out}
+	return tests
 }