Documentation
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Overview ¶
Package standalone holds the input handling shared by standalone scripts that declare their own command-line interface: value parsing, positional validation, help annotations, and usage errors.
Index ¶
- Constants
- func AnnotateFlags(set *pflag.FlagSet, declared []flags.Flag)
- func CheckBoolPositional(set *pflag.FlagSet, argv []string) error
- func DefaultName(filename string) string
- func DescribeArguments(cmd *cobra.Command, specs []*flags.PositionalArgSpec)
- func LabelListFlags(set *pflag.FlagSet)
- func NewUsageError(cmd *cobra.Command, invoked string, cause error) error
- func ParseDecimalInt(raw string) (int, error)
- func ParseStringList(raw string) ([]string, error)
- func ValidatePositionals(specs []*flags.PositionalArgSpec, positional []string) error
- type DecimalInt
- type ValueError
Constants ¶
const UsageExitCode = 2
UsageExitCode is the exit status for command-line input a script's interface does not accept, matching the convention of Atmos's own usage errors.
Variables ¶
This section is empty.
Functions ¶
func AnnotateFlags ¶
AnnotateFlags appends what the help output would otherwise omit to each declared flag's description: whether it is required, its allowed values, and the environment variable bound to it.
func CheckBoolPositional ¶
CheckBoolPositional rejects a true/false word that directly follows a boolean flag. Boolean flags never consume the next word, so `--verbose false` would silently turn the flag on and pass "false" as a positional argument.
func DefaultName ¶
DefaultName derives a command name from a script filename by dropping the extension, so help reads `Usage: tool [flags]` rather than `Usage: tool.star [flags]`. The result follows the same character rules as an explicit command name.
func DescribeArguments ¶
func DescribeArguments(cmd *cobra.Command, specs []*flags.PositionalArgSpec)
DescribeArguments adds an Arguments section to the command's help. Required arguments appear as <name> and optional ones as [name], matching the usage line. Arguments without a description are listed by name only, and a command with no arguments gets no section.
func LabelListFlags ¶
LabelListFlags renames the displayed type of string-list flags from `strings` to `list`. It replaces the flags' values, so call it only once parsing is finished and the values are no longer read.
func NewUsageError ¶
NewUsageError presents a failure to parse the user's command line as a usage error rather than a script failure. The invoked argument is the script as the user typed it, so the hint can be copied as-is.
func ParseDecimalInt ¶
ParseDecimalInt parses raw as a base-10 integer, for both command-line and environment values.
func ParseStringList ¶
ParseStringList splits a list value the way pflag's StringSlice does for command-line values: comma-separated, with CSV quoting for items that contain commas. An empty value is an empty list.
func ValidatePositionals ¶
func ValidatePositionals(specs []*flags.PositionalArgSpec, positional []string) error
ValidatePositionals checks the number of positional values against the declared arguments and names the first missing required argument.
Types ¶
type DecimalInt ¶
type DecimalInt struct {
// contains filtered or unexported fields
}
DecimalInt is a pflag.Value for integer flags. Unlike pflag's own integer flags it accepts only base-10 digits, so `010` is ten and `0x10` is rejected instead of being read as octal or hex.
func NewDecimalInt ¶
func NewDecimalInt(initial int) *DecimalInt
NewDecimalInt creates a DecimalInt holding the flag's default value.
func (*DecimalInt) String ¶
func (v *DecimalInt) String() string
String returns the current value in decimal, which is the text pflag reads typed values from.
func (*DecimalInt) Type ¶
func (v *DecimalInt) Type() string
Type names the flag type shown in help output.
type ValueError ¶
ValueError reports why a flag value was rejected. Its message is the bare reason: the callers that surface it add the flag name and, for environment values, the variable, so a sentinel prefix here would repeat in the output. It still satisfies errors.Is(err, ErrInvalidFlagValue).
func (*ValueError) Is ¶
func (e *ValueError) Is(target error) bool
Is makes every value error satisfy ErrInvalidFlagValue.
func (*ValueError) Unwrap ¶
func (e *ValueError) Unwrap() error
Unwrap exposes the underlying parse error, if any.
Source Files