refactor validateOpts

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

4 files changed, 119 insertions, 98 deletions

diff --git a/cmd/gomplate/main.go b/cmd/gomplate/main.go
index c962214b..a11ea931 100644
--- a/cmd/gomplate/main.go
+++ b/cmd/gomplate/main.go
@@ -5,7 +5,6 @@ The gomplate command
 package main
 
 import (
-	"errors"
 	"fmt"
 	"os"
 	"os/exec"
@@ -24,40 +23,6 @@ var (
 	includes []string
 )
 
-// nolint: gocyclo
-func validateOpts(cmd *cobra.Command, args []string) error {
-	if cmd.Flag("in").Changed && cmd.Flag("file").Changed {
-		return errors.New("--in and --file may not be used together")
-	}
-
-	if len(opts.InputFiles) != len(opts.OutputFiles) {
-		return fmt.Errorf("must provide same number of --out (%d) as --file (%d) options", len(opts.OutputFiles), len(opts.InputFiles))
-	}
-
-	if cmd.Flag("input-dir").Changed && (cmd.Flag("in").Changed || cmd.Flag("file").Changed) {
-		return errors.New("--input-dir can not be used together with --in or --file")
-	}
-
-	if cmd.Flag("output-dir").Changed {
-		if cmd.Flag("out").Changed {
-			return errors.New("--output-dir can not be used together with --out")
-		}
-		if !cmd.Flag("input-dir").Changed {
-			return errors.New("--input-dir must be set when --output-dir is set")
-		}
-	}
-
-	if cmd.Flag("output-map").Changed {
-		if cmd.Flag("out").Changed || cmd.Flag("output-dir").Changed {
-			return errors.New("--output-map can not be used together with --out or --output-dir")
-		}
-		if !cmd.Flag("input-dir").Changed {
-			return errors.New("--input-dir must be set when --output-map is set")
-		}
-	}
-	return nil
-}
-
 func printVersion(name string) {
 	fmt.Printf("%s version %s\n", name, version.Version)
 }
diff --git a/cmd/gomplate/main_test.go b/cmd/gomplate/main_test.go
index f29e4978..e0d74e9d 100644
--- a/cmd/gomplate/main_test.go
+++ b/cmd/gomplate/main_test.go
@@ -3,72 +3,9 @@ package main
 import (
 	"testing"
 
-	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/assert"
 )
 
-func TestValidateOpts(t *testing.T) {
-	err := validateOpts(parseFlags(), nil)
-	assert.NoError(t, err)
-
-	cmd := parseFlags("-i=foo", "-f", "bar")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("-i=foo", "-o=bar", "-o=baz")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("-i=foo", "--input-dir=baz")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("--input-dir=foo", "-f=bar")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("--output-dir=foo", "-o=bar")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("--output-dir=foo")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("--output-map", "bar")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags("-o", "foo", "--output-map", "bar")
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags(
-		"--input-dir", "in",
-		"--output-dir", "foo",
-		"--output-map", "bar",
-	)
-	err = validateOpts(cmd, nil)
-	assert.Error(t, err)
-
-	cmd = parseFlags(
-		"--input-dir", "in",
-		"--output-map", "bar",
-	)
-	err = validateOpts(cmd, nil)
-	assert.NoError(t, err)
-}
-
-func parseFlags(flags ...string) *cobra.Command {
-	cmd := &cobra.Command{}
-	initFlags(cmd)
-	err := cmd.ParseFlags(flags)
-	if err != nil {
-		panic(err)
-	}
-	return cmd
-}
-
 func TestProcessIncludes(t *testing.T) {
 	data := []struct {
 		inc, exc, expected []string
diff --git a/cmd/gomplate/validate.go b/cmd/gomplate/validate.go
new file mode 100644
index 00000000..68c132b8
--- /dev/null
+++ b/cmd/gomplate/validate.go
@@ -0,0 +1,59 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/spf13/cobra"
+)
+
+func notTogether(cmd *cobra.Command, flags ...string) error {
+	found := ""
+	for _, flag := range flags {
+		f := cmd.Flag(flag)
+		if f != nil && f.Changed {
+			if found != "" {
+				a := make([]string, len(flags))
+				for i := range a {
+					a[i] = "--" + flags[i]
+				}
+				return fmt.Errorf("only one of these flags is supported at a time: %s", strings.Join(a, ", "))
+			}
+			found = flag
+		}
+	}
+	return nil
+}
+
+func mustTogether(cmd *cobra.Command, left, right string) error {
+	l := cmd.Flag(left)
+	if l != nil && l.Changed {
+		r := cmd.Flag(right)
+		if r != nil && !r.Changed {
+			return fmt.Errorf("--%s must be set when --%s is set", right, left)
+		}
+	}
+
+	return nil
+}
+
+func validateOpts(cmd *cobra.Command, args []string) (err error) {
+	err = notTogether(cmd, "in", "file", "input-dir")
+	if err == nil {
+		err = notTogether(cmd, "out", "output-dir", "output-map", "exec-pipe")
+	}
+
+	if err == nil && len(opts.InputFiles) != len(opts.OutputFiles) {
+		err = fmt.Errorf("must provide same number of --out (%d) as --file (%d) options", len(opts.OutputFiles), len(opts.InputFiles))
+	}
+
+	if err == nil {
+		err = mustTogether(cmd, "output-dir", "input-dir")
+	}
+
+	if err == nil {
+		err = mustTogether(cmd, "output-map", "input-dir")
+	}
+
+	return err
+}
diff --git a/cmd/gomplate/validate_test.go b/cmd/gomplate/validate_test.go
new file mode 100644
index 00000000..91f16767
--- /dev/null
+++ b/cmd/gomplate/validate_test.go
@@ -0,0 +1,60 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValidateOpts(t *testing.T) {
+	err := validateOpts(parseFlags())
+	assert.NoError(t, err)
+
+	err = validateOpts(parseFlags("-i=foo", "-f", "bar"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("-i=foo", "-o=bar", "-o=baz"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("-i=foo", "--input-dir=baz"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("--input-dir=foo", "-f=bar"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("--output-dir=foo", "-o=bar"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("--output-dir=foo"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("--output-map", "bar"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags("-o", "foo", "--output-map", "bar"))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags(
+		"--input-dir", "in",
+		"--output-dir", "foo",
+		"--output-map", "bar",
+	))
+	assert.Error(t, err)
+
+	err = validateOpts(parseFlags(
+		"--input-dir", "in",
+		"--output-map", "bar",
+	))
+	assert.NoError(t, err)
+}
+
+func parseFlags(flags ...string) (cmd *cobra.Command, args []string) {
+	cmd = &cobra.Command{}
+	initFlags(cmd)
+	err := cmd.ParseFlags(flags)
+	if err != nil {
+		panic(err)
+	}
+	return cmd, cmd.Flags().Args()
+}