feat(cli): add cliarg package

jsjoeio · jsjoeio · commit b3017955486c · 2022-05-12T22:13:40.000Z
This adds a new package called `cliarg` with tests which adds a helper
function  that extends cobra.Args to allow for custom error messages.
diff --git a/cli/cliarg/cliarg.go b/cli/cliarg/cliarg.go
@@ -0,0 +1,28 @@
+// Package cliarg extends cobra.Args to allow for custom error messages.
+//
+// Usage:
+//
+// cliarg.ExactNamedArgs("workspace", "This command requires a workspace name to be passed. Run this command with '--help' to see an example.")
+//
+// Will produce the following error message when calling
+//
+//   Error: this command accepts 'workspace' as an argument, received no arguments. Pass in 'workspace' or call command with '--help' to see an example.")
+//
+package cliarg
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+// Expects 1 arg based on namedArg, otherwise returns customErrorMessage
+func ExactNamedArg(namedArg string, customErrorMessage string) cobra.PositionalArgs {
+	return func(cmd *cobra.Command, args []string) error {
+		expectedNumOfArgs := 1
+		if len(args) != expectedNumOfArgs {
+			return fmt.Errorf("this command accepts <%s> as an argument, received no arguments. %s", namedArg, customErrorMessage)
+		}
+		return nil
+	}
+}
diff --git a/cli/cliarg/cliflag_test.go b/cli/cliarg/cliflag_test.go
@@ -0,0 +1,34 @@
+package cliarg_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/coder/coder/cli/cliarg"
+	"github.com/coder/coder/cli/clitest"
+)
+
+func TestCliarg(t *testing.T) {
+	t.Run("No errors", func(t *testing.T) {
+		t.Parallel()
+		namedArg := "workspace"
+		customErrorMessage := "Please call with a workspace arg"
+		fun := cliarg.ExactNamedArg(namedArg, customErrorMessage)
+		args := []string{"myWorkspace"}
+		cmd, _ := clitest.New(t, "delete", "myWorkspace")
+		var want *string
+		got := fun(cmd, args)
+		require.Nil(t, want, got)
+	})
+	t.Run("Custom error message", func(t *testing.T) {
+		t.Parallel()
+		namedArg := "workspace"
+		customErrorMessage := "Please call with a workspace arg"
+		fun := cliarg.ExactNamedArg(namedArg, customErrorMessage)
+		var args []string
+		cmd, _ := clitest.New(t, "delete")
+		got := fun(cmd, args)
+		require.ErrorContains(t, got, customErrorMessage)
+	})
+}
