Add FlaggedCommand interface so the framework owns flag parsing#27
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Add FlaggedCommand interface so the framework owns flag parsing#27
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Introduce FlaggedCommand/FlaggedHandlerFunc to builtins.go: the framework creates a *pflag.FlagSet per invocation, calls the command's MakeFlags factory to register flags and get a bound handler, then runs Parse and error reporting before dispatching with positional args only. Commands no longer contain boilerplate for fs.SetOutput, fs.Parse, or parse-error formatting. Expose type FlagSet = pflag.FlagSet via the builtins package so command files can use *builtins.FlagSet in their factory signature without importing pflag directly (the builtins package is always-allowed in the import allowlist). Add Registrable interface (Register method on both Command and FlaggedCommand) so register_builtins.go can hold both types in one slice. Convert head to FlaggedCommand as the first consumer of the new interface. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Replace the parallel Command/FlaggedCommand/HandlerFunc/BoundHandlerFunc/
FlaggedHandlerFunc/Registrable surface with one type each:
Command { Name string; MakeFlags func(*FlagSet) HandlerFunc }
HandlerFunc func(ctx, callCtx, args) Result
Every command declares its flags via MakeFlags. The framework creates a fresh
*FlagSet per invocation, calls MakeFlags to register flags and get the bound
handler, then parses raw args before calling the handler with positional args.
Commands with no flags (echo, cat, break, continue, true, false, exit) use the
NoFlags helper which wraps a plain HandlerFunc. The framework detects that no
flags were registered via fs.HasFlags() and skips parsing entirely, so
flag-shaped literals like "echo -n hello" are passed through unchanged.
register_builtins.go now iterates a single []builtins.Command.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
AlexandreYang
approved these changes
Mar 10, 2026
pflag.ContinueOnError, pflag.NewFlagSet, and io.Discard moved into builtins.go (the framework layer, exempt from the allowlist) as part of the FlaggedCommand consolidation. No command implementation file references these symbols anymore. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Merge from main brought in a reimplemented cat and a new wc command, both using the old Run field and manually calling pflag.NewFlagSet / io.Discard inside their run functions. This broke the build (unknown field Run) and would have failed the import allowlist (pflag.NewFlagSet, pflag.ContinueOnError, and io.Discard were removed from the allowlist in this PR). Convert both to registerFlags(fs *builtins.FlagSet) builtins.HandlerFunc, removing the pflag import from each file. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
julesmcrt
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Mar 10, 2026
- Convert tail.go from Run to MakeFlags/HandlerFunc pattern, matching the framework change merged from origin/main (PR #27). - Remove pflag import; framework now owns FlagSet creation and parsing. - Drop pflag.ContinueOnError, pflag.NewFlagSet, and io.Discard from the import allowlist — no builtin implementation file uses them directly. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
AlexandreYang
added a commit
that referenced
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Mar 10, 2026
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Introduce FlaggedCommand/FlaggedHandlerFunc to builtins.go: the framework creates a *pflag.FlagSet per invocation, calls the command's MakeFlags factory to register flags and get a bound handler, then runs Parse and error reporting before dispatching with positional args only. Commands no longer contain boilerplate for fs.SetOutput, fs.Parse, or parse-error formatting.
Expose type FlagSet = pflag.FlagSet via the builtins package so command files can use *builtins.FlagSet in their factory signature without importing pflag directly (the builtins package is always-allowed in the import allowlist).
Add Registrable interface (Register method on both Command and FlaggedCommand) so register_builtins.go can hold both types in one slice.
Convert head to FlaggedCommand as the first consumer of the new interface.