use TempFile though the testing is gross

pkg/cmd/pr/shared/preserve.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
-	"time"
 
 	"github.com/cli/cli/pkg/iostreams"
 )
@@ -40,9 +39,17 @@ func PreserveInput(io *iostreams.IOStreams, state *IssueMetadataState, createErr
 			return
 		}
 
-		dp := dumpPath(time.Now().UnixNano())
+		tmpfile, err := io.TempFile(os.TempDir(), "gh*.json")
+		if err != nil {
+			fmt.Fprintf(out, "failed to save input to file: %s\n", err)
+			fmt.Fprintln(out, "would have saved:")
+			fmt.Fprintf(out, "%v\n", state)
+			return
+		}
 
-		err = io.WriteFile(dp, data)
+		tmpfilePath := filepath.Join(os.TempDir(), tmpfile.Name())
+
+		_, err = tmpfile.Write(data)
 		if err != nil {
 			fmt.Fprintf(out, "failed to save input to file: %s\n", err)
 			fmt.Fprintln(out, "would have saved:")
@@ -57,8 +64,8 @@ func PreserveInput(io *iostreams.IOStreams, state *IssueMetadataState, createErr
 			issueType = "issue"
 		}
 
-		fmt.Fprintf(out, "%s operation failed. input saved to: %s\n", cs.FailureIcon(), dp)
-		fmt.Fprintf(out, "resubmit with: gh %s create -j@%s\n", issueType, dp)
+		fmt.Fprintf(out, "%s operation failed. input saved to: %s\n", cs.FailureIcon(), tmpfilePath)
+		fmt.Fprintf(out, "resubmit with: gh %s create -j@%s\n", issueType, tmpfilePath)
 
 		// some whitespace before the actual error
 		fmt.Fprintln(out)

pkg/cmd/pr/shared/preserve_test.go

@@ -3,6 +3,7 @@ package shared
 import (
 	"encoding/json"
 	"errors"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -12,12 +13,6 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func Test_dumpPath(t *testing.T) {
-	// mostly pointless test
-	var random int64 = 1234567890
-	assert.Equal(t, dumpPath(random), filepath.Join(os.TempDir(), "gh602d2.json"))
-}
-
 func Test_PreserveInput(t *testing.T) {
 	tests := []struct {
 		name             string
@@ -50,8 +45,8 @@ func Test_PreserveInput(t *testing.T) {
 				Labels:    []string{"sandwich"},
 			},
 			wantErrLines: []string{
-				`X operation failed. input saved to:.*\.json`,
-				`resubmit with: gh issue create -j@.*\.json`,
+				`X operation failed. input saved to:.*testfile.*`,
+				`resubmit with: gh issue create -j@.*testfile.*`,
 			},
 			err:              true,
 			wantPreservation: true,
@@ -63,8 +58,8 @@ func Test_PreserveInput(t *testing.T) {
 				Labels:    []string{"sandwich"},
 			},
 			wantErrLines: []string{
-				`X operation failed. input saved to:.*\.json`,
-				`resubmit with: gh issue create -j@.*\.json`,
+				`X operation failed. input saved to:.*testfile.*`,
+				`resubmit with: gh issue create -j@.*testfile.*`,
 			},
 			err:              true,
 			wantPreservation: true,
@@ -77,8 +72,8 @@ func Test_PreserveInput(t *testing.T) {
 				Type:  PRMetadata,
 			},
 			wantErrLines: []string{
-				`X operation failed. input saved to:.*\.json`,
-				`resubmit with: gh pr create -j@.*\.json`,
+				`X operation failed. input saved to:.*testfile.*`,
+				`resubmit with: gh pr create -j@.*testfile.*`,
 			},
 			err:              true,
 			wantPreservation: true,
@@ -90,8 +85,15 @@ func Test_PreserveInput(t *testing.T) {
 			if tt.state == nil {
 				tt.state = &IssueMetadataState{}
 			}
+
 			io, _, _, errOut := iostreams.Test()
-			io.WriteOverride = []byte{}
+
+			tfPath, tf, tferr := tmpfile()
+			assert.NoError(t, tferr)
+			defer os.Remove(tfPath)
+
+			io.TempFileOverride = tf
+
 			var err error
 			if tt.err {
 				err = errors.New("error during creation")
@@ -99,16 +101,31 @@ func Test_PreserveInput(t *testing.T) {
 
 			PreserveInput(io, tt.state, &err)()
 
+			tf.Seek(0, 0)
+
+			data, err := ioutil.ReadAll(tf)
+			assert.NoError(t, err)
+
 			if tt.wantPreservation {
 				test.ExpectLines(t, errOut.String(), tt.wantErrLines...)
 				preserved := &IssueMetadataState{}
-				assert.NoError(t, json.Unmarshal(io.WriteOverride, preserved))
+				assert.NoError(t, json.Unmarshal(data, preserved))
 				preserved.dirty = tt.state.dirty
 				assert.Equal(t, preserved, tt.state)
 			} else {
 				assert.Equal(t, errOut.String(), "")
-				assert.Equal(t, string(io.WriteOverride), "")
+				assert.Equal(t, string(data), "")
 			}
 		})
 	}
 }
+
+func tmpfile() (string, *os.File, error) {
+	dir := os.TempDir()
+	tmpfile, err := ioutil.TempFile(dir, "testfile*")
+	if err != nil {
+		return "", nil, err
+	}
+
+	return filepath.Join(dir, tmpfile.Name()), tmpfile, nil
+}

pkg/iostreams/iostreams.go

@@ -46,7 +46,7 @@ type IOStreams struct {
 
 	neverPrompt bool
 
-	WriteOverride []byte
+	TempFileOverride *os.File
 }
 
 func (s *IOStreams) ColorEnabled() bool {
@@ -270,12 +270,12 @@ func (s *IOStreams) ReadUserFile(fn string) ([]byte, error) {
 	return ioutil.ReadAll(r)
 }
 
-func (s *IOStreams) WriteFile(fn string, data []byte) error {
-	if s.WriteOverride != nil {
-		s.WriteOverride = data
-		return nil
+func (s *IOStreams) TempFile(dir, pattern string) (*os.File, error) {
+	if s.TempFileOverride != nil {
+		fmt.Printf("DBG %#v\n", s.TempFileOverride)
+		return s.TempFileOverride, nil
 	}
-	return ioutil.WriteFile(fn, data, 0660)
+	return ioutil.TempFile(dir, pattern)
 }
 
 func System() *IOStreams {