Move tests next to their implementation

string.go → basic.go

@@ -11,8 +11,57 @@ import (
 	"html/template"
 	"reflect"
 	"strconv"
+	"time"
 )
 
+// ToBoolE casts an interface to a bool type.
+func ToBoolE(i interface{}) (bool, error) {
+	i = indirect(i)
+
+	switch b := i.(type) {
+	case bool:
+		return b, nil
+	case nil:
+		return false, nil
+	case int:
+		return b != 0, nil
+	case int64:
+		return b != 0, nil
+	case int32:
+		return b != 0, nil
+	case int16:
+		return b != 0, nil
+	case int8:
+		return b != 0, nil
+	case uint:
+		return b != 0, nil
+	case uint64:
+		return b != 0, nil
+	case uint32:
+		return b != 0, nil
+	case uint16:
+		return b != 0, nil
+	case uint8:
+		return b != 0, nil
+	case float64:
+		return b != 0, nil
+	case float32:
+		return b != 0, nil
+	case time.Duration:
+		return b != 0, nil
+	case string:
+		return strconv.ParseBool(i.(string))
+	case json.Number:
+		v, err := ToInt64E(b)
+		if err == nil {
+			return v != 0, nil
+		}
+		return false, fmt.Errorf("unable to cast %#v of type %T to bool", i, i)
+	default:
+		return false, fmt.Errorf("unable to cast %#v of type %T to bool", i, i)
+	}
+}
+
 // ToStringE casts an interface to a string type.
 func ToStringE(i interface{}) (string, error) {
 	switch s := i.(type) {

basic_test.go

@@ -0,0 +1,211 @@
+// Copyright © 2014 Steve Francia <[email protected]>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package cast
+
+import (
+	"encoding/json"
+	"html/template"
+	"testing"
+	"time"
+
+	qt "github.com/frankban/quicktest"
+)
+
+func TestToBoolE(t *testing.T) {
+	c := qt.New(t)
+
+	var jf, jt, je json.Number
+	_ = json.Unmarshal([]byte("0"), &jf)
+	_ = json.Unmarshal([]byte("1"), &jt)
+	_ = json.Unmarshal([]byte("1.0"), &je)
+	tests := []struct {
+		input  interface{}
+		expect bool
+		iserr  bool
+	}{
+		{0, false, false},
+		{int64(0), false, false},
+		{int32(0), false, false},
+		{int16(0), false, false},
+		{int8(0), false, false},
+		{uint(0), false, false},
+		{uint64(0), false, false},
+		{uint32(0), false, false},
+		{uint16(0), false, false},
+		{uint8(0), false, false},
+		{float64(0), false, false},
+		{float32(0), false, false},
+		{time.Duration(0), false, false},
+		{jf, false, false},
+		{nil, false, false},
+		{"false", false, false},
+		{"FALSE", false, false},
+		{"False", false, false},
+		{"f", false, false},
+		{"F", false, false},
+		{false, false, false},
+
+		{"true", true, false},
+		{"TRUE", true, false},
+		{"True", true, false},
+		{"t", true, false},
+		{"T", true, false},
+		{1, true, false},
+		{int64(1), true, false},
+		{int32(1), true, false},
+		{int16(1), true, false},
+		{int8(1), true, false},
+		{uint(1), true, false},
+		{uint64(1), true, false},
+		{uint32(1), true, false},
+		{uint16(1), true, false},
+		{uint8(1), true, false},
+		{float64(1), true, false},
+		{float32(1), true, false},
+		{time.Duration(1), true, false},
+		{jt, true, false},
+		{je, true, false},
+		{true, true, false},
+		{-1, true, false},
+		{int64(-1), true, false},
+		{int32(-1), true, false},
+		{int16(-1), true, false},
+		{int8(-1), true, false},
+
+		// errors
+		{"test", false, true},
+		{testing.T{}, false, true},
+	}
+
+	for i, test := range tests {
+		errmsg := qt.Commentf("i = %d", i) // assert helper message
+
+		v, err := ToBoolE(test.input)
+		if test.iserr {
+			c.Assert(err, qt.IsNotNil)
+			continue
+		}
+
+		c.Assert(err, qt.IsNil)
+		c.Assert(v, qt.Equals, test.expect, errmsg)
+
+		// Non-E test
+		v = ToBool(test.input)
+		c.Assert(v, qt.Equals, test.expect, errmsg)
+	}
+}
+
+func BenchmarkTooBool(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		if !ToBool(true) {
+			b.Fatal("ToBool returned false")
+		}
+	}
+}
+
+func TestToStringE(t *testing.T) {
+	c := qt.New(t)
+
+	var jn json.Number
+	_ = json.Unmarshal([]byte("8"), &jn)
+	type Key struct {
+		k string
+	}
+	key := &Key{"foo"}
+
+	tests := []struct {
+		input  interface{}
+		expect string
+		iserr  bool
+	}{
+		{int(8), "8", false},
+		{int8(8), "8", false},
+		{int16(8), "8", false},
+		{int32(8), "8", false},
+		{int64(8), "8", false},
+		{uint(8), "8", false},
+		{uint8(8), "8", false},
+		{uint16(8), "8", false},
+		{uint32(8), "8", false},
+		{uint64(8), "8", false},
+		{float32(8.31), "8.31", false},
+		{float64(8.31), "8.31", false},
+		{jn, "8", false},
+		{true, "true", false},
+		{false, "false", false},
+		{nil, "", false},
+		{[]byte("one time"), "one time", false},
+		{"one more time", "one more time", false},
+		{template.HTML("one time"), "one time", false},
+		{template.URL("http://somehost.foo"), "http://somehost.foo", false},
+		{template.JS("(1+2)"), "(1+2)", false},
+		{template.CSS("a"), "a", false},
+		{template.HTMLAttr("a"), "a", false},
+		// errors
+		{testing.T{}, "", true},
+		{key, "", true},
+	}
+
+	for i, test := range tests {
+		errmsg := qt.Commentf("i = %d", i) // assert helper message
+
+		// Non-E test
+		v := ToString(test.input)
+		c.Assert(v, qt.Equals, test.expect, errmsg)
+
+		// Non-pointer test
+		v, err := ToStringE(test.input)
+		if test.iserr {
+			c.Assert(err, qt.IsNotNil, errmsg)
+		} else {
+			c.Assert(err, qt.IsNil, errmsg)
+			c.Assert(v, qt.Equals, test.expect, errmsg)
+		}
+
+		// Pointer test
+		v, err = ToStringE(&test.input)
+		if test.iserr {
+			c.Assert(err, qt.IsNotNil, errmsg)
+		} else {
+			c.Assert(err, qt.IsNil, errmsg)
+			c.Assert(v, qt.Equals, test.expect, errmsg)
+		}
+	}
+}
+
+type foo struct {
+	val string
+}
+
+func (x foo) String() string {
+	return x.val
+}
+
+func TestStringerToString(t *testing.T) {
+	c := qt.New(t)
+
+	var x foo
+	x.val = "bar"
+	c.Assert(ToString(x), qt.Equals, "bar", qt.Commentf("non-pointer test"))
+	c.Assert(ToString(&x), qt.Equals, "bar", qt.Commentf("pointer test"))
+}
+
+type fu struct {
+	val string
+}
+
+func (x fu) Error() string {
+	return x.val
+}
+
+func TestErrorToString(t *testing.T) {
+	c := qt.New(t)
+
+	var x fu
+	x.val = "bar"
+	c.Assert(ToString(x), qt.Equals, "bar", qt.Commentf("non-pointer test"))
+	c.Assert(ToString(&x), qt.Equals, "bar", qt.Commentf("pointer test"))
+}