Rewrite ghostel-compile: spawn directly, add opt-in global mode

[dakra]

Summary

Addresses @dalgong's comment on #104: multi-line shell paragraphs don't work well with the current ghostel-compile, and the OSC 133 / shell-integration dependency is fragile.

• Spawn the command directly. ghostel-compile now runs shell-file-name -c COMMAND via make-process through a PTY owned by the ghostel renderer — no interactive shell between the command and the user. Multi-line scripts are passed verbatim. Completion is detected by the process sentinel, so no OSC 133 markers (or shell integration) are required.
• Add opt-in ghostel-compile-global-mode. Advises compilation-start so compile, recompile, project-compile, and every other compilation-start caller run in ghostel automatically. grep-mode falls through by default; customisable via ghostel-compile-global-mode-excluded-modes.
• Simplify. Drops ghostel-compile-hide-prompts and ghostel-compile-clear-buffer (no shell = no prompts to hide, buffer is always recreated fresh). Drops the --running state machine, finalize-timer gating, OSC 133 C/D handlers, and the bash shell-integration exit-status regression test.

Behaviour changes for users

• No shell-integration required for ghostel-compile to work.
• Multi-line shell paragraphs work (main bug report).
• Customs gone: ghostel-compile-hide-prompts, ghostel-compile-clear-buffer.
• New toggle: M-x ghostel-compile-global-mode — opt-in, routes all compile-style commands through ghostel.

Test plan

• make -j4 all — 120 elisp tests + 72 native tests, lint clean
• make test-evil — 30 tests pass
• Live: multi-line script (for i in 1 2 3; do echo $i; done; exit 7) runs, reports exit 7, output visible
• Live: ghostel-recompile re-runs the last command
• Live: ghostel-compile-global-mode 1 → M-x compile routes through ghostel (*compilation* buffer in ghostel-compile-view-mode)
• Live: error output gets parsed — /tmp/x.c:12:3: error: ... picked up, mode-line shows :exit [1]
• New tests covering: multi-line shell, idempotent finalize, global-mode advice add/remove, grep-mode fallthrough, custom mode exclusions, advice routing

[Copilot]

Pull request overview

Reworks ghostel-compile to run compilation commands by spawning shell-file-name -c COMMAND directly under a Ghostel-owned PTY (no interactive shell / OSC 133 dependency), and adds an opt-in global mode to route all compilation-start callers through Ghostel.

Changes:

• Replace OSC-133-driven completion detection with process-sentinel finalization for ghostel-compile.
• Add ghostel-compile-global-mode (around-advice on compilation-start) with exclusions for modes like grep-mode.
• Update tests and README to reflect the new lifecycle and global mode behavior.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
ghostel-compile.el	Rewrites spawn/finalize flow to use a sentinel and introduces ghostel-compile-global-mode + new buffer setup path.
test/ghostel-test.el	Removes OSC-133-specific tests and adds tests for sentinel idempotence and global-mode routing/fallthrough behavior.
README.md	Documents direct spawning behavior and the new global mode toggle/configuration.

Comments suppressed due to low confidence (1)

README.md:583

• The README section still states that completion is detected via OSC 133 D;<exit> and that ghostel-shell-integration must be active. That’s no longer true for ghostel-compile after this rewrite (it now finalizes via the process sentinel). Please update/relocate this paragraph to clarify that OSC 133 is only required for the general ghostel-command-*-functions hooks, not for ghostel-compile completion/exit status.

Completion is detected via the OSC 133 `D;<exit>` semantic prompt
marker, so shell integration (`ghostel-shell-integration`, enabled by
default) must be active.

---

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[Copilot]

This test doesn’t exercise the ghostel-compile implementation—it only verifies /bin/sh -c can run a multi-line script. To actually guard the regression, consider stubbing ghostel-compile--spawn/make-process (or ghostel-compile--start) and asserting the spawned argv includes shell-file-name, shell-command-switch, and the exact COMMAND string (including newlines) without re-encoding/splitting.

Suggested change

	"Regression: multi-line shell paragraphs must be passed verbatim to `sh -c'.
	`ghostel-compile' spawns `sh -c COMMAND' directly, so embedded
	newlines in COMMAND are parsed by the shell as normal script lines
	rather than mangled by a line-editing shell as RET presses."
	(skip-unless (file-executable-p "/bin/sh"))
	(let* ((script "for i in 1 2 3; do\n echo line-$i\ndone\nexit 7"))
	(with-temp-buffer
	(let ((status (call-process "/bin/sh" nil t nil "-c" script)))
	(should (equal 7 status))
	(let ((out (buffer-string)))
	(should (string-match-p "line-1" out))
	(should (string-match-p "line-2" out))
	(should (string-match-p "line-3" out)))))))
	"Regression: `ghostel-compile--start' must pass multi-line COMMAND verbatim.
	This test exercises the Ghostel compile path directly and asserts the
	spawned argv contains `shell-file-name', `shell-command-switch', and
	the exact COMMAND string including embedded newlines."
	(let* ((script "for i in 1 2 3; do\n echo line-$i\ndone\nexit 7")
	(captured-command nil)
	(test-buffer (generate-new-buffer " *ghostel-test-compile*")))
	(unwind-protect
	(cl-letf (((symbol-function 'make-process)
	(lambda (&rest args)
	(setq captured-command (plist-get args :command))
	'ghostel-test-process))
	((symbol-function 'set-process-query-on-exit-flag)
	(lambda (&rest _) nil))
	((symbol-function 'process-put)
	(lambda (&rest _) nil))
	((symbol-function 'set-process-filter)
	(lambda (&rest _) nil))
	((symbol-function 'set-process-sentinel)
	(lambda (&rest _) nil))
	((symbol-function 'process-buffer)
	(lambda (&rest _) test-buffer))
	((symbol-function 'display-buffer)
	(lambda (&rest _) test-buffer))
	((symbol-function 'get-buffer-create)
	(lambda (&rest _) test-buffer))
	((symbol-function 'generate-new-buffer)
	(lambda (&rest _) test-buffer)))
	(ghostel-compile--start script "*ghostel multiline*" default-directory)
	(should (equal shell-file-name (nth 0 captured-command)))
	(should (equal shell-command-switch (nth 1 captured-command)))
	(should (equal script (nth 2 captured-command))))
	(when (buffer-live-p test-buffer)
	(kill-buffer test-buffer)))))