feat(print) add Print, Printf, Fprint, and Fprintf functions

go.mod

@@ -2,4 +2,7 @@ module github.com/jimeh/undent
 
 go 1.15
 
-require github.com/stretchr/testify v1.6.1
+require (
+	github.com/rhysd/go-fakeio v1.0.0
+	github.com/stretchr/testify v1.6.1
+)

go.sum

@@ -2,6 +2,8 @@ github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rhysd/go-fakeio v1.0.0 h1:+TjiKCOs32dONY7DaoVz/VPOdvRkPfBkEyUDIpM8FQY=
+github.com/rhysd/go-fakeio v1.0.0/go.mod h1:joYxF906trVwp2JLrE4jlN7A0z6wrz8O6o1UjarbFzE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=

undent.go

@@ -4,6 +4,7 @@ package undent
 
 import (
 	"fmt"
+	"io"
 	"regexp"
 )
 
@@ -60,3 +61,38 @@ func String(s string) string {
 func Stringf(format string, a ...interface{}) string {
 	return fmt.Sprintf(String(format), a...)
 }
+
+// Print will undent any strings arguments before passing them to fmt.Print.
+func Print(a ...interface{}) (n int, err error) {
+	return fmt.Print(undentInterfaces(a)...)
+}
+
+// Printf will undent the given format string before passing it and all
+// arguments to fmt.Printf.
+func Printf(format string, a ...interface{}) (n int, err error) {
+	return fmt.Printf(String(format), a...)
+}
+
+// Fprint will undent any string arguments before passing them to fmt.Fprint.
+func Fprint(w io.Writer, a ...interface{}) (n int, err error) {
+	return fmt.Fprint(w, undentInterfaces(a)...)
+}
+
+// Fprintf will undent the given format string before passing it and all
+// arguments to fmt.Fprintf.
+func Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
+	return fmt.Fprintf(w, String(format), a...)
+}
+
+func undentInterfaces(a []interface{}) []interface{} {
+	var r []interface{}
+
+	for _, v := range a {
+		if s, ok := v.(string); ok {
+			v = String(s)
+		}
+		r = append(r, v)
+	}
+
+	return r
+}

undent_example_test.go

@@ -1,6 +1,7 @@
 package undent_test
 
 import (
+	"bytes"
 	"fmt"
 
 	"github.com/jimeh/undent"
@@ -60,3 +61,57 @@ func ExampleStringf() {
 	//   "hello": "world"
 	// }
 }
+
+func ExamplePrint() {
+	undent.Print(`
+		{
+		  "hello": "world"
+		}`,
+	)
+	// Output:
+	// {
+	//   "hello": "world"
+	// }
+}
+
+func ExamplePrintf() {
+	undent.Printf(`
+		{
+		  "hello": "%s"
+		}`,
+		"world",
+	)
+	// Output:
+	// {
+	//   "hello": "world"
+	// }
+}
+
+func ExampleFprint() {
+	var buf bytes.Buffer
+	undent.Fprint(&buf, `
+		{
+		  "hello": "world"
+		}`,
+	)
+	fmt.Println(buf.String())
+	// Output:
+	// {
+	//   "hello": "world"
+	// }
+}
+
+func ExampleFprintf() {
+	var buf bytes.Buffer
+	undent.Fprintf(&buf, `
+		{
+		  "hello": "%s"
+		}`,
+		"world",
+	)
+	fmt.Println(buf.String())
+	// Output:
+	// {
+	//   "hello": "world"
+	// }
+}

undent_test.go

@@ -1,9 +1,12 @@
 package undent
 
 import (
+	"bytes"
 	"testing"
 
+	"github.com/rhysd/go-fakeio"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 var stringTestCases = []struct {
@@ -443,6 +446,62 @@ func TestStringf(t *testing.T) {
 	}
 }
 
+func TestPrint(t *testing.T) {
+	for _, tt := range stringTestCases {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := fakeio.Stdout().Do(func() {
+				Print(tt.s, 5, tt.s)
+			})
+			require.NoError(t, err)
+
+			assert.IsType(t, "", got)
+			assert.Equal(t, tt.want+"5"+tt.want, got)
+		})
+	}
+}
+
+func TestPrintf(t *testing.T) {
+	for _, tt := range stringfTestCases {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := fakeio.Stdout().Do(func() {
+				Printf(tt.s, tt.a...)
+			})
+			require.NoError(t, err)
+
+			assert.IsType(t, "", got)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}
+
+func TestFprint(t *testing.T) {
+	for _, tt := range stringTestCases {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+
+			Fprint(&buf, tt.s, 5, tt.s)
+			got := buf.String()
+
+			assert.IsType(t, "", got)
+			assert.Equal(t, tt.want+"5"+tt.want, got)
+		})
+	}
+}
+
+func TestFprintf(t *testing.T) {
+	for _, tt := range stringfTestCases {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+
+			Fprintf(&buf, tt.s, tt.a...)
+			got := buf.String()
+
+			assert.IsType(t, "", got)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}
+
 func BenchmarkBytes(b *testing.B) {
 	for _, tt := range stringTestCases {
 		b.Run(tt.name, func(b *testing.B) {