Add `predicate' arg to `read-buffer' and use it for erc-iswitchb

Fixes: debbugs:20116

* src/minibuf.c (Fread_buffer): Add `predicate' argument.
* src/callint.c (Fcall_interactively): Adjust calls accordingly.

* lisp/erc/erc.el (erc-switch-to-buffer): Rename from erc-iswitchb and rewrite
using read-buffer.
(erc--buffer-p): New function, extracted from erc-buffer-filter.
(erc-buffer-filter): Use it.
(erc-with-all-buffers-of-server): Silence compile warning if the return
value is unused.
(erc-is-valid-nick-p, erc-common-server-suffixes, erc-get-arglist)
(erc-command-name, erc-popup-input-buffer): Use \` and \' to match
beg/end of string.

* lisp/obsolete/iswitchb.el (iswitchb-read-buffer): Add `predicate' arg.
* lisp/isearchb.el (isearchb-iswitchb): Adjust accordingly.
* lisp/ido.el (ido-read-buffer): Add `predicate' argument.
* lisp/misearch.el (unload-function-defs-list): Declare before use.

1 files changed, 4 insertions, 0 deletions

diff --git a/etc/NEWS b/etc/NEWS
index 24ed0799b2c..cabd0087d92 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -594,6 +594,8 @@ a typographically-correct documents.
 
 * Incompatible Lisp Changes in Emacs 25.1
 
+** read-buffer-function can now be called with a 4th argument (`predicate').
+
 ** completion-table-dynamic stays in the minibuffer.
 If you want the old behavior of calling the function in the buffer
 from which the minibuffer was entered, call it with the new argument
@@ -631,6 +633,8 @@ word syntax, use `\sw' instead.
 
 * Lisp Changes in Emacs 25.1
 
+** `read-buffer' takes a new `predicate' argument.
+
 ** Emacs Lisp now supports generators.
 
 ** New finalizer facility for running code when objects