Add the command people type first, and stop crashing on the fallback path

[n1ckyb]

Four defects found by using the CLI the way a new user would.

intentumdiff diff did not exist

The first thing anyone types, and it failed:

Error: No such command 'diff'. Did you mean 'gist-diff'?

A suggestion pointing away from the two commands that actually diff things. Now aliased to file.

This needed registering in both layers. The entry point is a Click group in _parser.py that registers commands by name and delegates to argparse — and the Click group rejects unknown commands before argparse is ever consulted, so aliases=["diff"] on the argparse subparser alone changed nothing. (Tell them apart by the error: Click says "Try 'intentumdiff --help'", argparse prints usage:.)

--json was rejected, though JSON output already existed

intentumdiff: error: unrecognized arguments: --json

It has always been available as --format json. An error that denies a feature we actually ship is worse than a missing feature, because it teaches the user the tool cannot do it. Added as a store_const alias.

The fallback path crashed while rendering its own output

The token-level fallback description contained U+2192. A Windows console is cp1252, so Rich raised UnicodeEncodeError and printed

Error: 'charmap' codec can't encode character '\u2192'

inside the results table — on exactly the files that had already failed to parse. Same for an em dash in the accompanying log line. Both ASCII now.

A retired distribution failed silently and totally

Both intentdiff (pre-rebrand) and intentumdiff-python install the same intentumdiff import package. With both present, the resolved distribution name can be the retired one — which is not in the first-party trust allowlist. Every bundled parser is then rejected as untrusted, and the user sees a stream of

IntentumDiff error: native_fallback: parse errors require Python token fallback

and no diff at all. Nothing in that chain names the cause, and the failure is total rather than partial, so it reads as "the tool is broken". This is the same defect class that made 0.0.1 unusable, so it now warns at startup naming the fix.

Verification

In the source repo: diff returns a change · --json emits JSON · the fallback table renders without the crash · stderr is 0 bytes on a clean run.

pyproject.toml is deliberately not synced — the version already matches (0.0.2b1) and this branch's comment wording differs from the monorepo's.

🤖 Generated with Claude Code

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Check the actual legacy distribution before warning

When the unrelated bare intentdiff project is installed, this lookup emits a false collision warning and directs the user to uninstall that package. The repository’s released pre-rebrand package was named intentdiff-python and installed the intentdiff import package, whereas the current distribution installs intentumdiff; therefore the checked distribution neither represents the retired release nor shares this import package. Remove this warning or base collision detection on distributions that actually own intentumdiff.

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