New random namespace for generating random strings and numbers

Signed-off-by: Dave Henderson <dhenderson@gmail.com>

1 files changed, 127 insertions, 0 deletions

diff --git a/random/random_test.go b/random/random_test.go
new file mode 100644
index 00000000..7b6b49af
--- /dev/null
+++ b/random/random_test.go
@@ -0,0 +1,127 @@
+package random
+
+import (
+	"math"
+	"testing"
+	"unicode/utf8"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMatchChars(t *testing.T) {
+	in := "[a-g]"
+	expected := []rune("abcdefg")
+	out, err := matchChars(in)
+	assert.NoError(t, err)
+	assert.EqualValues(t, expected, out)
+
+	in = "[a-zA-Z0-9_.-]"
+	expected = []rune(defaultSet)
+	out, err = matchChars(in)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, out)
+
+	in = "[[:alpha:]]"
+	expected = []rune("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz")
+	out, err = matchChars(in)
+	assert.NoError(t, err)
+	assert.Equal(t, expected, out)
+}
+
+func TestStringRE(t *testing.T) {
+	r, err := StringRE(15, "[\\p{Yi}[:alnum:]]")
+	assert.NoError(t, err)
+	assert.Equal(t, 15, utf8.RuneCountInString(r))
+
+	_, err = StringRE(1, "[bogus")
+	assert.Error(t, err)
+}
+
+func TestStringBounds(t *testing.T) {
+	_, err := StringBounds(15, 0, 19)
+	assert.Error(t, err)
+
+	// surrogate range isn't valid, should error
+	_, err = StringBounds(15, 0xd800, 0xdfff)
+	assert.Error(t, err)
+
+	r, err := StringBounds(1, 'a', 'a')
+	assert.NoError(t, err)
+	assert.Equal(t, "a", r)
+
+	r, err = StringBounds(99, 'a', 'b')
+	assert.NoError(t, err)
+	assert.Regexp(t, "^[a-b]+$", r)
+
+	r, err = StringBounds(100, 0x0020, 0x007f)
+	assert.NoError(t, err)
+	assert.Regexp(t, "^[\u0020-\u007f]*$", r)
+
+	// only 🂱 (\U0001F0B1) in this range is "graphic"
+	r, err = StringBounds(8, 0x0001f0af, 0x0001f0b1)
+	assert.NoError(t, err)
+	assert.Regexp(t, "^🂱🂱🂱🂱🂱🂱🂱🂱$", r)
+}
+
+func TestItem(t *testing.T) {
+	_, err := Item(nil)
+	assert.Error(t, err)
+
+	i, err := Item([]interface{}{"foo"})
+	assert.NoError(t, err)
+	assert.Equal(t, "foo", i)
+
+	in := []interface{}{"foo", "bar"}
+	got := ""
+	for j := 0; j < 10; j++ {
+		i, err = Item(in)
+		assert.NoError(t, err)
+		got += i.(string)
+	}
+	assert.NotEqual(t, "foofoofoofoofoofoofoofoofoofoo", got)
+	assert.NotEqual(t, "barbarbarbarbarbarbarbarbarbar", got)
+}
+
+func TestNumber(t *testing.T) {
+	_, err := Number(0, -1)
+	assert.Error(t, err)
+	_, err = Number(0, math.MaxInt64)
+	assert.Error(t, err)
+	_, err = Number(math.MinInt64, 0)
+	assert.Error(t, err)
+
+	testdata := []struct {
+		min, max, expected int64
+		delta              float64
+	}{
+		{0, 100, 50, 50},
+		{0, 0, 0, 0},
+		{9, 9, 9, 0},
+		{-10, -10, -10, 0},
+		{-10, -0, -5, 5},
+	}
+	for _, d := range testdata {
+		n, err := Number(d.min, d.max)
+		assert.NoError(t, err)
+		assert.InDelta(t, d.expected, n, d.delta)
+	}
+}
+
+func TestFloat(t *testing.T) {
+	testdata := []struct {
+		min, max, expected float64
+		delta              float64
+	}{
+		{0, 1.0, 0.5, 0.5},
+		{0, 0.5, 0.25, 0.25},
+		{490, 500, 495, 5},
+		{-500, 500, 0, 500},
+		{0, math.MaxFloat64, math.MaxFloat64 / 2, math.MaxFloat64 / 2},
+	}
+
+	for _, d := range testdata {
+		n, err := Float(d.min, d.max)
+		assert.NoError(t, err)
+		assert.InDelta(t, d.expected, n, d.delta)
+	}
+}