Previously, you could only use this when setting the handle afterwards.

* lisp/eshell/esh-io.el (eshell-set-output-handle): Don't catch
'eshell-null-device' here...
(eshell-get-target): ... catch it here.

* test/lisp/eshell/eshell-tests.el
(eshell-test/eshell-command/output-dev-null): New test (bug#72857).

* lisp/eshell/esh-io.el (eshell-output-object-to-target): Don't require
TARGET to be bound.

* lisp/eshell/em-script.el (eshell-execute-file):
* lisp/eshell/eshell.el (eshell-command): Quote the output/error
targets.

* test/lisp/eshell/em-script-tests.el (eshell-execute-file-output): New
variable.
(em-script-test/execute-file/output-symbol): New test.

* test/lisp/eshell/eshell-tests.el (eshell-command-output): New
variable.
(eshell-test/eshell-command/output-symbol): New test (bug#72857).

* lisp/eshell/em-alias.el (eshell-write-aliases-list):
* lisp/eshell/em-script.el (eshell-batch-file):
* lisp/eshell/esh-cmd.el (eshell-command-to-value):
* lisp/eshell/eshell.el (eshell-command): Use 'eshell-with-handles'.

* test/lisp/eshell/esh-io-tests.el (eshell-test-file-string): Move to...
* test/lisp/eshell/eshell-tests-helpers.el (eshell-test-file-string):
... here.

* test/lisp/eshell/eshell-tests.el
(eshell-test/eshell-command/output-file):
* test/lisp/eshell/em-script-tests.el
(em-script-test/execute-file/output-file): New tests.

This makes sure we close the handles as we should, which is important
for writing the output to an actual file (bug#72857).

* lisp/eshell/em-script.el (esh-cmd): Require this, just to be explicit.
(eshell-execute-file): Use 'eshell-with-handles'.

See bug#72220.

* lisp/eshell/esh-cmd.el (eshell-with-handles): New macro...
(eshell-commands): ... use it.
(eshell-with-copied-handles): Remove STEAL-P and allow multiple body
forms (this is an incompatible change, but the macro is currently
internal despite the name).
(eshell-parse-command, eshell-do-pipelines)
(eshell-do-pipelines-synchronously, eshell--invoke-command-directly-p):
Remove handle stealing.
(eshell-structure-basic-command, eshell-do-command)
(eshell-lisp-command): Remove 'eshell-close-handles'.
(eshell-protect): Make obsolete.
(eshell-rewrite-for-command, eshell-rewrite-while-command)
(eshell-rewrite-if-command, (eshell-parse-pipeline): Remove
'eshell-protect'.

* lisp/eshell/esh-io.el (eshell-duplicate-handles): Make STEAL-P
obsolete.

* lisp/eshell/esh-proc.el (eshell-gather-process-output): Call
'eshell-protect-handles' one more time.  Remove 'eshell-close-handles'.

* lisp/eshell/esh-var.el (eshell-parse-variable-ref): Reimplement
$<COMMAND> form using 'eshell-with-handles'.

* test/lisp/eshell/esh-cmd-tests.el
(esh-cmd-test/command-not-found/pipeline): New test.

* test/lisp/eshell/em-tramp-tests.el
(em-tramp-test/should-replace-command): Adjust check for
'eshell-with-copied-handles'.

* lisp/eshell/esh-cmd.el (eshell-do-eval): Make sure that replacing 'if'
forms returns the correct result, and evaluate to 'nil' for 'progn'
forms with no body.

Previously, the exit info in Eshell was that of the last command that
finished, rather than the last command in a pipeline.

* lisp/eshell/esh-cmd.el (eshell-exec-lisp)
(eshell-lisp-command): Check whether the command is being piped.

* lisp/eshell/esh-proc.el (eshell-gather-process-output): Record whether
the command is being piped...
(eshell-sentinel): ... and do the right thing with that info.

* test/lisp/eshell/esh-proc-tests.el
(esh-proc-test/sigpipe-exits-process): Check the exit status to ensure
we don't report the first process's SIGPIPE exit.

* lisp/eshell/esh-cmd.el (eshell-last-command-status)
(eshell-last-command-result): Move here from esh-io.el.
(eshell-set-exit-info): New function, extracted from
'eshell-close-handles'.

* lisp/eshell/esh-io.el (eshell-close-handles): Make old calling
convention obsolete.  Update callers to use 'eshell-set-exit-info' as
needed.