fix/bug-48598 dd5a99e891 26/27: SQUASH-ME: Add ERC test scenario for erc-cmd-JOIN

[F. Jason Park]

branch: fix/bug-48598
commit dd5a99e89108f8b87104886445d703cf3670797c
Author: F. Jason Park <jp@neverwas.me>
Commit: F. Jason Park <jp@neverwas.me>

    SQUASH-ME: Add ERC test scenario for erc-cmd-JOIN
    
    DELETE THIS NOTE: This scenario belongs here because it indirectly
    asserts that the changes to erc-cmd-JOIN work as intended.  See note
    atop the `ert-deftest' and helper.
    
    The assertion involving the presence of an entry for the current user
    in a defunct channel buffer has to do with trying to shift to a
    cleaner means of checking whether a channel buffer is subscribed
    to (whether it's JOINed or PARTed).  The old means of checking,
    basically seeing whether `erc-default-target' is non-nil, depends on
    `erc-default-recipients', whose purpose has never been well defined.
---
 .../base/reuse-buffers/channel-buffers/barnet.eld  |  68 +++++++++++++
 .../base/reuse-buffers/channel-buffers/foonet.eld  |  66 +++++++++++++
 test/lisp/erc/erc-scenarios.el                     | 109 +++++++++++++++++++++
 3 files changed, 243 insertions(+)

diff --git 
a/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/barnet.eld
 
b/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/barnet.eld
new file mode 100644
index 0000000000..c90c399aed
--- /dev/null
+++ 
b/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/barnet.eld
@@ -0,0 +1,68 @@
+;; -*- mode: lisp-data; -*-
+((pass 1 "PASS :barnet:changeme"))
+((nick 1 "NICK tester"))
+((user 1 "USER user 0 * :tester")
+ (0 ":irc.barnet.org 001 tester :Welcome to the barnet IRC Network tester")
+ (0 ":irc.barnet.org 002 tester :Your host is irc.barnet.org, running version 
oragono-2.6.0-7481bf0385b95b16")
+ (0 ":irc.barnet.org 003 tester :This server was created Wed, 05 May 2021 
09:05:33 UTC")
+ (0 ":irc.barnet.org 004 tester irc.barnet.org oragono-2.6.0-7481bf0385b95b16 
BERTZios CEIMRUabefhiklmnoqstuv Iabefhkloqv")
+ (0 ":irc.barnet.org 005 tester AWAYLEN=390 BOT=B CASEMAPPING=ascii 
CHANLIMIT=#:100 CHANMODES=Ibe,k,fl,CEMRUimnstu CHANNELLEN=64 CHANTYPES=# 
ELIST=U EXCEPTS EXTBAN=,m FORWARD=f INVEX KICKLEN=390 :are supported by this 
server")
+ (0 ":irc.barnet.org 005 tester MAXLIST=beI:60 MAXTARGETS=4 MODES MONITOR=100 
NETWORK=barnet NICKLEN=32 PREFIX=(qaohv)~&@%+ STATUSMSG=~&@%+ 
TARGMAX=NAMES:1,LIST:1,KICK:1,WHOIS:1,USERHOST:10,PRIVMSG:4,TAGMSG:4,NOTICE:4,MONITOR:100
 TOPICLEN=390 UTF8MAPPING=rfc8265 UTF8ONLY WHOX :are supported by this server")
+ (0 ":irc.barnet.org 005 tester draft/CHATHISTORY=100 :are supported by this 
server")
+ (0 ":irc.barnet.org 251 tester :There are 0 users and 3 invisible on 1 
server(s)")
+ (0 ":irc.barnet.org 252 tester 0 :IRC Operators online")
+ (0 ":irc.barnet.org 254 tester 1 :channels formed")
+ (0 ":irc.barnet.org 255 tester :I have 3 clients and 0 servers")
+ (0 ":irc.barnet.org 265 tester 3 3 :Current local users 3, max 3")
+ (0 ":irc.barnet.org 266 tester 3 3 :Current global users 3, max 3")
+ (0 ":irc.barnet.org 422 tester :MOTD File is missing"))
+
+((mode-user 1.2 "MODE tester +i")
+ ;; No mode answer
+ (0 ":irc.znc.in 306 tester :You have been marked as being away")
+ (0 ":tester!~u@wvys46tx8tpmk.irc JOIN #chan")
+ (0 ":irc.barnet.org 353 tester = #chan :joe @mike tester")
+ (0 ":irc.barnet.org 366 tester #chan :End of /NAMES list.")
+ (0 ":***!znc@znc.in PRIVMSG #chan :Buffer Playback...")
+ (0 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:16] joe: Tush! none but 
minstrels like of sonneting.")
+ (0 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:19] mike: Prithee, 
nuncle, be contented; 'tis a naughty night to swim in. Now a little fire in a 
wide field were like an old lecher's heart; a small spark, all the rest on's 
body cold. Look! here comes a walking fire.")
+ (0 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:22] joe: My name is 
Edgar, and thy father's son.")
+ (0 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:26] mike: Good my lord, 
be good to me; your honour is accounted a merciful man; good my lord.")
+ (0 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:31] joe: Thy child shall 
live, and I will see it nourish'd.")
+ (0 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :[09:09:33] mike: Quick, quick; 
fear nothing; I'll be at thy elbow.")
+ (0 ":***!znc@znc.in PRIVMSG #chan :Playback Complete.")
+ (0 ":irc.barnet.org NOTICE tester :[09:05:35] This server is in debug mode 
and is logging all user I/O. If you do not wish for everything you send to be 
readable by the server owner(s), please disconnect.")
+ (0 ":irc.barnet.org 305 tester :You are no longer marked as being away"))
+
+((mode 1 "MODE #chan")
+ (0 ":irc.barnet.org 324 tester #chan +nt")
+ (0 ":irc.barnet.org 329 tester #chan 1620205534")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: That will be given to 
the loudest noise we make.")
+ (0.1 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: If it please your 
honour, I am the poor duke's constable, and my name is Elbow: I do lean upon 
justice, sir; and do bring in here before your good honour two notorious 
benefactors.")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Following the signs, 
woo'd but the sign of she.")
+ (0.5 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: That, sir, which I will 
not report after her.")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Boyet, prepare: I will 
away to-night.")
+ (0.1 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: If the man be a 
bachelor, sir, I can; but if he be a married man, he is his wife's head, and I 
can never cut off a woman's head.")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Thyself upon thy 
virtues, they on thee.")
+ (0.1 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: Arm it in rags, a 
pigmy's straw doth pierce it."))
+
+((part 5.1 "PART #chan :" quit)
+ (0 ":tester!~u@wvys46tx8tpmk.irc PART #chan :" quit))
+
+((join 10.1 "JOIN #chan")
+ (0 ":tester!~u@wvys46tx8tpmk.irc JOIN #chan")
+ (0 ":irc.barnet.org 353 tester = #chan :@mike joe tester")
+ (0 ":irc.barnet.org 366 tester #chan :End of NAMES list")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :tester, welcome!")
+ (0 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :tester, welcome!"))
+
+((mode 1 "MODE #chan")
+ (0 ":irc.barnet.org 324 tester #chan +nt")
+ (0 ":irc.barnet.org 329 tester #chan 1620205534")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Chi non te vede, non te 
pretia.")
+ (0.1 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: Well, if ever thou dost 
fall from this faith, thou wilt prove a notable argument.")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Of heavenly oaths, vow'd 
with integrity.")
+ (0.1 ":joe!~u@wvys46tx8tpmk.irc PRIVMSG #chan :mike: These herblets shall, 
which we upon you strew.")
+ (0.1 ":mike!~u@wvys46tx8tpmk.irc PRIVMSG #chan :joe: Aaron will have his soul 
black like his face."))
+
+((linger 0.5 LINGER))
diff --git 
a/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/foonet.eld
 
b/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/foonet.eld
new file mode 100644
index 0000000000..648321875b
--- /dev/null
+++ 
b/test/lisp/erc/erc-scenarios-resources/base/reuse-buffers/channel-buffers/foonet.eld
@@ -0,0 +1,66 @@
+;; -*- mode: lisp-data; -*-
+((pass 1 "PASS :foonet:changeme"))
+((nick 1 "NICK tester"))
+((user 1 "USER user 0 * :tester")
+ (0 ":irc.foonet.org 001 tester :Welcome to the foonet IRC Network tester")
+ (0 ":irc.foonet.org 002 tester :Your host is irc.foonet.org, running version 
oragono-2.6.0-7481bf0385b95b16")
+ (0 ":irc.foonet.org 003 tester :This server was created Wed, 05 May 2021 
09:05:34 UTC")
+ (0 ":irc.foonet.org 004 tester irc.foonet.org oragono-2.6.0-7481bf0385b95b16 
BERTZios CEIMRUabefhiklmnoqstuv Iabefhkloqv")
+ (0 ":irc.foonet.org 005 tester AWAYLEN=390 BOT=B CASEMAPPING=ascii 
CHANLIMIT=#:100 CHANMODES=Ibe,k,fl,CEMRUimnstu CHANNELLEN=64 CHANTYPES=# 
ELIST=U EXCEPTS EXTBAN=,m FORWARD=f INVEX KICKLEN=390 :are supported by this 
server")
+ (0 ":irc.foonet.org 005 tester MAXLIST=beI:60 MAXTARGETS=4 MODES MONITOR=100 
NETWORK=foonet NICKLEN=32 PREFIX=(qaohv)~&@%+ STATUSMSG=~&@%+ 
TARGMAX=NAMES:1,LIST:1,KICK:1,WHOIS:1,USERHOST:10,PRIVMSG:4,TAGMSG:4,NOTICE:4,MONITOR:100
 TOPICLEN=390 UTF8MAPPING=rfc8265 UTF8ONLY WHOX :are supported by this server")
+ (0 ":irc.foonet.org 005 tester draft/CHATHISTORY=100 :are supported by this 
server")
+ (0 ":irc.foonet.org 251 tester :There are 0 users and 3 invisible on 1 
server(s)")
+ (0 ":irc.foonet.org 252 tester 0 :IRC Operators online")
+ (0 ":irc.foonet.org 254 tester 1 :channels formed")
+ (0 ":irc.foonet.org 255 tester :I have 3 clients and 0 servers")
+ (0 ":irc.foonet.org 265 tester 3 3 :Current local users 3, max 3")
+ (0 ":irc.foonet.org 266 tester 3 3 :Current global users 3, max 3")
+ (0 ":irc.foonet.org 422 tester :MOTD File is missing"))
+
+((mode-user 1.2 "MODE tester +i")
+ ;; No mode answer
+ (0 ":irc.znc.in 306 tester :You have been marked as being away")
+ (0 ":tester!~u@247eaxkrufj44.irc JOIN #chan")
+ (0 ":irc.foonet.org 353 tester = #chan :alice @bob tester")
+ (0 ":irc.foonet.org 366 tester #chan :End of /NAMES list.")
+ (0 ":***!znc@znc.in PRIVMSG #chan :Buffer Playback...")
+ (0 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:07:19] bob: Is this; she 
hath bought the name of whore thus dearly.")
+ (0 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:07:24] alice: He sent to me, 
sir,Here he comes.")
+ (0 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:07:26] bob: Till I torment 
thee for this injury.")
+ (0 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:07:29] alice: There's an 
Italian come; and 'tis thought, one of Leonatus' friends.")
+ (0 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:09:33] bob: Ay, and the 
particular confirmations, point from point, to the full arming of the verity.")
+ (0 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :[09:09:35] alice: Kneel in the 
streets and beg for grace in vain.")
+ (0 ":***!znc@znc.in PRIVMSG #chan :Playback Complete.")
+ (0 ":irc.foonet.org NOTICE tester :[09:06:05] This server is in debug mode 
and is logging all user I/O. If you do not wish for everything you send to be 
readable by the server owner(s), please disconnect.")
+ (0 ":irc.foonet.org 305 tester :You are no longer marked as being away"))
+
+((mode 1 "MODE #chan")
+ (0 ":irc.foonet.org 324 tester #chan +nt")
+ (0 ":irc.foonet.org 329 tester #chan 1620205534")
+ (0.5 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: Nor I no strength to 
climb without thy help.")
+ (0.1 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :bob: Nothing, but let him 
have thanks. Demand of him my condition, and what credit I have with the duke.")
+ (0.1 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: Show me this piece. I 
am joyful of your sights.")
+ (0.2 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :bob: Whilst I can shake my 
sword or hear the drum."))
+
+((part 5 "PART #chan :" quit)
+ (0 ":tester!~u@247eaxkrufj44.irc PART #chan :" quit))
+
+((join 10 "JOIN #chan")
+ (0 ":tester!~u@247eaxkrufj44.irc JOIN #chan")
+ (0 ":irc.foonet.org 353 tester = #chan :@bob alice tester")
+ (0 ":irc.foonet.org 366 tester #chan :End of NAMES list")
+ (0.1 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :tester, welcome!")
+ (0 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :tester, welcome!"))
+
+((mode 1 "MODE #chan")
+ (0 ":irc.foonet.org 324 tester #chan +nt")
+ (0 ":irc.foonet.org 329 tester #chan 1620205534")
+ (0.1 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: Thou desirest me to 
stop in my tale against the hair.")
+ (0.1 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :bob: And dar'st not stand, 
nor look me in the face.")
+ (0.1 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: It should not be, by 
the persuasion of his new feasting.")
+ (0.1 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :bob: It was not given me, 
nor I did not buy it.")
+ (0.1 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: He that would vouch it 
in any place but here.")
+ (0.1 ":alice!~u@yppdd5tt4admc.irc PRIVMSG #chan :bob: In everything I wait 
upon his will.")
+ (0.1 ":bob!~u@yppdd5tt4admc.irc PRIVMSG #chan :alice: Thou counterfeit'st 
most lively."))
+
+((linger 8 LINGER))
diff --git a/test/lisp/erc/erc-scenarios.el b/test/lisp/erc/erc-scenarios.el
index e4857ab84d..8f311a06bc 100644
--- a/test/lisp/erc/erc-scenarios.el
+++ b/test/lisp/erc/erc-scenarios.el
@@ -1013,6 +1013,115 @@ collisions involving bouncers in ERC.  Run EXTRA."
         erc-reuse-buffers)
     (erc-scenarios-common--base-reuse-buffers-server-buffers)))
 
+;; This also asserts that `erc-cmd-JOIN' is no longer susceptible to a
+;; regression introduced in 28.1 (ERC 5.4) that caused phantom target
+;; buffers of the form target/server to be created via
+;; `switch-to-buffer' ("phantom" because they would go unused").  This
+;; would happen (in place of a JOIN being sent out) when a previously
+;; used (parted) target buffer existed and `erc-reuse-buffers' was
+;; nil.
+;;
+;; Note: All the `erc-get-channel-user' calls have to do with the fact
+;; that `erc-default-target' relies on the less-than-well-defined
+;; `erc-default-recipients' and is thus overloaded in the sense of
+;; being used both for retrieving a target name and checking if
+;; channel has been PARTed.  While not ideal, `erc-get-channel-user'
+;; can (also) be used to detect the latter.
+
+(defun erc-scenarios-common--base-reuse-buffers-channel-buffers ()
+  "The option `erc-reuse-buffers' is still respected when nil.
+Adapted from scenario clash-of-chans/uniquify described in Bug#48598:
+28.0.50; buffer-naming collisions involving bouncers in ERC."
+  (let ((expect (erc-d-t-make-expecter))
+        (server-process-bar (with-current-buffer "barnet" erc-server-process))
+        (server-process-foo (with-current-buffer "foonet" erc-server-process)))
+
+    (ert-info ("Unique #chan buffers exist")
+      (let ((chan-bufs (erc-scenarios-common-buflist "#chan"))
+            (names '("#chan@barnet" "#chan@foonet")))
+        (should (member (buffer-name (pop chan-bufs)) names))
+        (should (member (buffer-name (pop chan-bufs)) names))
+        (should-not chan-bufs)))
+
+    (ert-info ("#chan@foonet is exclusive and not contaminated")
+      (with-current-buffer "#chan@foonet"
+        (funcall expect 1 "<bob>")
+        (erc-d-t-absent-for 0.1 "<joe>")
+        (funcall expect 1 "strength to climb")
+        (should (eq erc-server-process server-process-foo))))
+
+    (ert-info ("#chan@barnet is exclusive and not contaminated")
+      (with-current-buffer "#chan@barnet"
+        (funcall expect 1 "<joe>")
+        (erc-d-t-absent-for 0.1 "<bob>")
+        (funcall expect 1 "the loudest noise")
+        (should (eq erc-server-process server-process-bar))))
+
+    (ert-info ("Part #chan@foonet")
+      (with-current-buffer "#chan@foonet"
+        (erc-d-t-search-for 1 "shake my sword")
+        (erc-cmd-PART "#chan")
+        (funcall expect 3 "You have left channel #chan")
+        (erc-cmd-JOIN "#chan")))
+
+    (ert-info ("Part #chan@barnet")
+      (with-current-buffer "#chan@barnet"
+        (funcall expect 3 "Arm it in rags")
+        (should (erc-get-channel-user (erc-current-nick)))
+        (erc-cmd-PART "#chan")
+        (funcall expect 3 "You have left channel #chan")
+        (should-not (erc-get-channel-user (erc-current-nick)))
+        (erc-cmd-JOIN "#chan")))
+
+    (erc-d-t-wait-for 3 "New unique target buffer for #chan@foonet created"
+      (get-buffer "#chan@foonet<2>"))
+
+    (ert-info ("Activity continues in new, <n>-suffixed #chan@foonet buffer")
+      (with-current-buffer "#chan@foonet"
+        (should-not (erc-get-channel-user (erc-current-nick))))
+      (with-current-buffer "#chan@foonet<2>"
+        (should (erc-get-channel-user (erc-current-nick)))
+        (funcall expect 2 "You have joined channel #chan")
+        (funcall expect 2 "#chan was created on")
+        (funcall expect 2 "<alice>")
+        (should (eq erc-server-process server-process-foo))
+        (erc-d-t-absent-for 0.2 "<joe>")))
+
+    (erc-d-t-wait-for 3 "New unique target buffer for #chan@barnet created"
+      (get-buffer "#chan@barnet<2>"))
+
+    (ert-info ("Activity continues in new, <n>-suffixed #chan@barnet buffer")
+      (with-current-buffer "#chan@barnet"
+        (should-not (erc-get-channel-user (erc-current-nick))))
+      (with-current-buffer "#chan@barnet<2>"
+        (funcall expect 2 "You have joined channel #chan")
+        (funcall expect 1 "Users on #chan: @mike joe tester")
+        (funcall expect 2 "<mike>")
+        (should (eq erc-server-process server-process-bar))
+        (erc-d-t-absent-for 0.2 "<bob>")))
+
+    (ert-info ("Two new chans created for a total of four")
+      (let* ((bufs (erc-scenarios-common-buflist "#chan"))
+             (names (sort (mapcar #'buffer-name bufs) #'string<)))
+        (should (equal names '("#chan@barnet" "#chan@barnet<2>"
+                               "#chan@foonet" "#chan@foonet<2>")))))
+
+    (ert-info ("All output sent")
+      (with-current-buffer "#chan@foonet<2>"
+        (while (accept-process-output server-process-foo))
+        (funcall expect 3 "most lively"))
+      (with-current-buffer "#chan@barnet<2>"
+        (while (accept-process-output server-process-bar))
+        (funcall expect 3 "soul black")))))
+
+(ert-deftest erc-scenarios-base-reuse-buffers-channel-buffers--disabled ()
+  (should erc-reuse-buffers)
+  (let ((erc-scenarios-common-dialog "base/reuse-buffers/channel-buffers")
+        (erc-server-flood-penalty 0.1)
+        erc-reuse-buffers)
+    (erc-scenarios-common--base-reuse-buffers-server-buffers
+     #'erc-scenarios-common--base-reuse-buffers-channel-buffers)))
+
 ;; The server changes your nick just after registration.
 
 (ert-deftest erc-scenarios-base-renick-self-auto ()