Don't use Go 1.16 features

Author: florisvdg

internals/secrethub/migrate_config_envfile.go

@@ -3,6 +3,7 @@ package secrethub
 import (
 	"bytes"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"regexp"
 
@@ -29,7 +30,7 @@ func (cmd *MigrateConfigEnvfileCommand) Run() error {
 		filepath = "secrethub.env"
 	}
 
-	inFileContents, err := os.ReadFile(filepath)
+	inFileContents, err := ioutil.ReadFile(filepath)
 	if err != nil {
 		return ErrReadFile(filepath, err)
 	}

internals/secrethub/migrate_config_references.go

@@ -3,7 +3,6 @@ package secrethub
 import (
 	"fmt"
 	"io/ioutil"
-	"os"
 	"regexp"
 	"strings"
 
@@ -61,7 +60,7 @@ func migrateReferences(inFile string, outFile string, mapping referenceMapping)
 		return nil, fmt.Errorf("no 1Password equivalent present in your migration plan for the following secrets:\n- %s", strings.Join(misses, "\n- "))
 	}
 
-	err = os.WriteFile(outFile, []byte(output), 0666)
+	err = ioutil.WriteFile(outFile, []byte(output), 0666)
 	if err != nil {
 		return nil, err
 	}

internals/secrethub/migrate_config_templates.go

@@ -3,6 +3,7 @@ package secrethub
 import (
 	"fmt"
 	"io"
+	"io/ioutil"
 	"os"
 	"regexp"
 	"strings"
@@ -48,7 +49,7 @@ func (cmd *MigrateConfigTemplatesCommand) Run() error {
 }
 
 func migrateTemplateTags(inFile io.Reader, outFile io.Writer, mapping referenceMapping, formatString string) ([]string, error) {
-	raw, err := io.ReadAll(inFile)
+	raw, err := ioutil.ReadAll(inFile)
 	if err != nil {
 		return nil, ErrReadFile(inFile, err)
 	}