Extension detection missed extensionless scripts — `scripts/deploy`, git
hooks, `configure`, and `scripts/bite` itself — so they got neither
highlighting nor an LSP server. Add a first-line shebang fallback.
- New `pmacs.parse.language_from_shebang(buf)` (builtin/runtime/syntax.lua):
sniffs the first line (capped at 256 bytes), maps the interpreter's
basename to a language, and resolves the `#!/usr/bin/env python3`
indirection (skipping env's own `-S`/flags and `VAR=val` assignments).
Backed by `pmacs.parse.shebangs`, a user-extensible map seeded with the
interpreters pmacs can act on: sh-family -> bash, python* -> python,
node -> javascript, lua* -> lua.
- Wired as a strict *fallback* on both resolution paths: syntax.lua's
grammar attach (`language_for_path or language_from_shebang`) and
lsp.lua's `buffer_language` (grammar -> filetypes -> shebang). A
recognized extension always wins, so a `.py`/`.sh` file is never
re-classified by a stray shebang.
- Cross-language, not shell-only: `#!/usr/bin/env python` /`node` /`lua`
resolve too. Special filenames (`.bashrc`, `Dockerfile`, `Makefile`)
are intentionally deferred until there are grammars behind them.
Bite-verified acceptance (tests/m4_acceptance.rs):
- m4_shebang_resolver_maps_interpreters — the mapping incl. env
indirection and `env -S`; non-shebangs and unmapped interpreters
(ruby) resolve to nil.
- m4_shebang_extensionless_script_resolves_bash — opening an
extensionless `#!/bin/sh` script resolves to bash on BOTH paths:
lsp.lua's `active_buffer_language()` and a settled bash parse tree
(grammar attach). Reachable only via the shebang, since the file has
no extension.
- m4_shebang_does_not_override_extension — a `.py` file opening with
`#!/bin/sh` still resolves to python (extension precedence).
Gates green: fmt; clippy -D warnings; test --lib; --features crdt;
m4_acceptance --skip basedpyright; GPU; full workspace sweep;
git diff --check. Change is Lua-only plus the acceptance tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YJ9FQ832QwftJXCD9LeFan
Levi Neuwirth
4a60e4c858