diff options
Diffstat (limited to 'lisp/eshell/esh-cmd.el')
| -rw-r--r-- | lisp/eshell/esh-cmd.el | 99 |
1 files changed, 59 insertions, 40 deletions
diff --git a/lisp/eshell/esh-cmd.el b/lisp/eshell/esh-cmd.el index 93f2616020c..94aa2ed8906 100644 --- a/lisp/eshell/esh-cmd.el +++ b/lisp/eshell/esh-cmd.el @@ -293,6 +293,17 @@ CDR are the same process. When the process in the CDR completes, resume command evaluation.") +(defvar eshell-allow-commands t + "If non-nil, allow evaluating command forms (including Lisp forms). +If you want to forbid command forms, you can let-bind this to a +non-nil value before calling `eshell-do-eval'. Then, any command +forms will signal `eshell-commands-forbidden'. This is useful +if, for example, you want to evaluate simple expressions like +variable expansions, but not fully-evaluate the command. See +also `eshell-complete-parse-arguments'.") + +(define-error 'eshell-commands-forbidden "Commands forbidden") + ;;; Functions: (defsubst eshell-interactive-process-p () @@ -410,7 +421,8 @@ hooks should be run before and after the command." (string= (car eshell--sep-terms) ";")) (eshell-parse-pipeline cmd) `(eshell-do-subjob - (list ,(eshell-parse-pipeline cmd))))) + (cons :eshell-background + ,(eshell-parse-pipeline cmd))))) (setq eshell--sep-terms (cdr eshell--sep-terms)) (if eshell-in-pipeline-p cmd @@ -531,9 +543,10 @@ of its argument (i.e., use of a Lisp special form), it must be implemented via rewriting, rather than as a function." (if (and (equal (car terms) "for") (equal (nth 2 terms) "in")) - (let ((body (car (last terms)))) + (let ((for-items (make-symbol "for-items")) + (body (car (last terms)))) (setcdr (last terms 2) nil) - `(let ((for-items + `(let ((,for-items (append ,@(mapcar (lambda (elem) @@ -541,13 +554,13 @@ implemented via rewriting, rather than as a function." elem `(list ,elem))) (nthcdr 3 terms))))) - (while for-items - (let ((,(intern (cadr terms)) (car for-items)) + (while ,for-items + (let ((,(intern (cadr terms)) (car ,for-items)) (eshell--local-vars (cons ',(intern (cadr terms)) eshell--local-vars))) (eshell-protect ,(eshell-invokify-arg body t))) - (setq for-items (cdr for-items))) + (setq ,for-items (cdr ,for-items))) (eshell-close-handles))))) (defun eshell-structure-basic-command (func names keyword test body @@ -675,13 +688,13 @@ This means an exit code of 0." (or (= (point-max) (1+ (point))) (not (eq (char-after (1+ (point))) ?\})))) (let ((end (eshell-find-delimiter ?\{ ?\}))) - (if (not end) - (throw 'eshell-incomplete "{") - (when (eshell-arg-delimiter (1+ end)) - (prog1 - `(eshell-as-subcommand - ,(eshell-parse-command (cons (1+ (point)) end))) - (goto-char (1+ end)))))))) + (unless end + (throw 'eshell-incomplete "{")) + (when (eshell-arg-delimiter (1+ end)) + (prog1 + `(eshell-as-subcommand + ,(eshell-parse-command (cons (1+ (point)) end))) + (goto-char (1+ end))))))) (defun eshell-parse-lisp-argument () "Parse a Lisp expression which is specified as an argument." @@ -881,7 +894,7 @@ This is used on systems where async subprocesses are not supported." (set headproc nil) (set tailproc nil) (progn - ,(if (fboundp 'make-process) + ,(if eshell-supports-asynchronous-processes `(eshell-do-pipelines ,pipeline) `(let ((tail-handles (eshell-duplicate-handles eshell-current-handles))) @@ -890,28 +903,33 @@ This is used on systems where async subprocesses are not supported." (symbol-value tailproc)))))) (defmacro eshell-as-subcommand (command) - "Execute COMMAND using a temp buffer. -This is used so that certain Lisp commands, such as `cd', when -executed in a subshell, do not disturb the environment of the main -Eshell buffer." + "Execute COMMAND as a subcommand. +A subcommand creates a local environment so that any changes to +the environment don't propagate outside of the subcommand's +scope. This lets you use commands like `cd' within a subcommand +without changing the current directory of the main Eshell +buffer." `(let ,eshell-subcommand-bindings ,command)) (defmacro eshell-do-command-to-value (object) "Run a subcommand prepared by `eshell-command-to-value'. This avoids the need to use `let*'." + (declare (obsolete nil "30.1")) `(let ((eshell-current-handles (eshell-create-handles value 'overwrite))) (progn ,object (symbol-value value)))) -(defmacro eshell-command-to-value (object) - "Run OBJECT synchronously, returning its result as a string. -Returns a string comprising the output from the command." - `(let ((value (make-symbol "eshell-temp")) - (eshell-in-pipeline-p nil)) - (eshell-do-command-to-value ,object))) +(defmacro eshell-command-to-value (command) + "Run an Eshell COMMAND synchronously, returning its output." + (let ((value (make-symbol "eshell-temp"))) + `(let ((eshell-in-pipeline-p nil) + (eshell-current-handles + (eshell-create-handles ',value 'overwrite))) + ,command + ,value))) ;;;_* Iterative evaluation ;; @@ -1019,7 +1037,12 @@ produced by `eshell-parse-command'." (cadr result))) (defun eshell-eval-command (command &optional input) - "Evaluate the given COMMAND iteratively." + "Evaluate the given COMMAND iteratively. +Return the process (or head and tail processes) created by +COMMAND, if any. If COMMAND is a background command, return the +process(es) in a cons cell like: + + (:eshell-background . PROCESS)" (if eshell-current-command ;; We can just stick the new command at the end of the current ;; one, and everything will happen as it should. @@ -1035,20 +1058,12 @@ produced by `eshell-parse-command'." (erase-buffer) (insert "command: \"" input "\"\n"))) (setq eshell-current-command command) - (let* ((delim (catch 'eshell-incomplete - (eshell-resume-eval))) - (val (car-safe delim))) - ;; If the return value of `eshell-resume-eval' is wrapped in a - ;; list, it indicates that the command was run asynchronously. - ;; In that case, unwrap the value before checking the delimiter - ;; value. - (if (and val - (not (eshell-processp val)) - (not (eq val t))) - (error "Unmatched delimiter: %S" val) - ;; Eshell-command expect a list like (<process>) to know if the - ;; command should be async or not. - (or (and (eshell-processp val) delim) val))))) + (let* (result + (delim (catch 'eshell-incomplete + (ignore (setq result (eshell-resume-eval)))))) + (when delim + (error "Unmatched delimiter: %S" delim)) + result))) (defun eshell-resume-command (proc status) "Resume the current command when a process ends." @@ -1168,7 +1183,7 @@ have been replaced by constants." (setcar (cdr args) (eshell-do-eval (cadr args) synchronous-p)) (eval form)) ((eq (car form) 'let) - (when (not (eq (car (cadr args)) 'eshell-do-eval)) + (unless (eq (car-safe (cadr args)) 'eshell-do-eval) (eshell-manipulate "evaluating let args" (dolist (letarg (car args)) (when (and (listp letarg) @@ -1328,6 +1343,8 @@ have been replaced by constants." (defun eshell-named-command (command &optional args) "Insert output from a plain COMMAND, using ARGS. COMMAND may result in an alias being executed, or a plain command." + (unless eshell-allow-commands + (signal 'eshell-commands-forbidden '(named))) (setq eshell-last-arguments args eshell-last-command-name (eshell-stringify command)) (run-hook-with-args 'eshell-prepare-command-hook) @@ -1465,6 +1482,8 @@ via `eshell-errorn'." (defun eshell-lisp-command (object &optional args) "Insert Lisp OBJECT, using ARGS if a function." + (unless eshell-allow-commands + (signal 'eshell-commands-forbidden '(lisp))) (catch 'eshell-external ; deferred to an external command (setq eshell-last-command-status 0 eshell-last-arguments args) |