Add support for more kinds of redirect operators in Eshell

* lisp/eshell/esh-arg.el: Require cl-lib.
(eshell-finish-arg): Allow passing multiple ARGUMENTS.
(eshell-quote-argument): Handle the case when 'eshell-finish-arg' was
passed multiple arguments.

* lisp/eshell/esh-cmd.el (eshell-do-pipelines)
(eshell-do-pipelines-synchronously): Only set stdout output handle.

* lisp/eshell/esh-io.el (eshell-redirection-operators-alist): New
constant.
(eshell-io-initialize): Prefer sharp quotes for functions.
(eshell-parse-redirection, eshell-strip-redirections): Add support for
more redirection forms.
(eshell-copy-output-handle, eshell-set-all-output-handles): New
functions.

* test/lisp/eshell/esh-io-tests.el
(esh-io-test/redirect-all/overwrite, esh-io-test/redirect-all/append)
(esh-io-test/redirect-all/insert, esh-io-test/redirect-copy)
(esh-io-test/redirect-copy-first, esh-io-test/redirect-pipe): New
tests.

* doc/misc/eshell.texi (Redirection): Document new redirection syntax.
(Pipelines): Document '|&' syntax.
(Bugs and ideas): Update item about redirection syntax.

* etc/NEWS: Announce this change.

1 files changed, 72 insertions, 0 deletions

diff --git a/test/lisp/eshell/esh-io-tests.el b/test/lisp/eshell/esh-io-tests.el
index 6cd2dff1c13..37b234eaf06 100644
--- a/test/lisp/eshell/esh-io-tests.el
+++ b/test/lisp/eshell/esh-io-tests.el
@@ -199,6 +199,78 @@
       (should (equal (buffer-string) "stderr\n")))
     (should (equal (buffer-string) "stdout\n"))))
 
+(ert-deftest esh-io-test/redirect-all/overwrite ()
+  "Check that redirecting to stdout and stderr via shorthand works."
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output &> #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "stdout\nstderr\n")))
+  ;; Also check the alternate (and less-preferred in Bash) `>&' syntax.
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output >& #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "stdout\nstderr\n"))))
+
+(ert-deftest esh-io-test/redirect-all/append ()
+  "Check that redirecting to stdout and stderr via shorthand works."
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output &>> #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "oldstdout\nstderr\n")))
+  ;; Also check the alternate (and less-preferred in Bash) `>>&' syntax.
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output >>& #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "oldstdout\nstderr\n"))))
+
+(ert-deftest esh-io-test/redirect-all/insert ()
+  "Check that redirecting to stdout and stderr via shorthand works."
+  (eshell-with-temp-buffer bufname "old"
+    (goto-char (point-min))
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output &>>> #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "stdout\nstderr\nold")))
+  ;; Also check the alternate `>>>&' syntax.
+  (eshell-with-temp-buffer bufname "old"
+    (goto-char (point-min))
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output >>>& #<%s>" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "stdout\nstderr\nold"))))
+
+(ert-deftest esh-io-test/redirect-copy ()
+  "Check that redirecting stdout and then copying stdout to stderr works.
+This should redirect both stdout and stderr to the same place."
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output > #<%s> 2>&1" bufname)
+                                  "\\`\\'"))
+    (should (equal (buffer-string) "stdout\nstderr\n"))))
+
+(ert-deftest esh-io-test/redirect-copy-first ()
+  "Check that copying stdout to stderr and then redirecting stdout works.
+This should redirect stdout to a buffer, and stderr to where
+stdout originally pointed (the terminal)."
+  (eshell-with-temp-buffer bufname "old"
+    (with-temp-eshell
+     (eshell-match-command-output (format "test-output 2>&1 > #<%s>" bufname)
+                                  "stderr\n"))
+    (should (equal (buffer-string) "stdout\n"))))
+
+(ert-deftest esh-io-test/redirect-pipe ()
+  "Check that \"redirecting\" to a pipe works."
+  ;; `|' should only redirect stdout.
+  (eshell-command-result-equal "test-output | rev"
+                               "stderr\ntuodts\n")
+  ;; `|&' should redirect stdout and stderr.
+  (eshell-command-result-equal "test-output |& rev"
+                               "tuodts\nrredts\n"))
+
 
 ;; Virtual targets