From 07fbdf4acc3b15ff97acb5c90243c61d938f8541 Mon Sep 17 00:00:00 2001
From: Jan Edmund Lazo <janedmundlazo@hotmail.com>
Date: Mon, 1 Oct 2018 22:57:49 -0400
Subject: vim-patch:8.0.1832: cannot use :unlet for an environment variable

Problem:    Cannot use :unlet for an environment variable.
Solution:   Make it work.  Use unsetenv() if available.
            (Yasuhiro Matsumoto, closes vim/vim#2855)
https://github.com/vim/vim/commit/137374fd6538cf9dee0cb22907728d8fdecb5832
---
 runtime/doc/eval.txt            |  8 ++++++++
 src/nvim/eval.c                 | 12 ++++++++++++
 src/nvim/testdir/test_unlet.vim | 24 ++++++++++++++++++++++++
 3 files changed, 44 insertions(+)

diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 064c08c190..2e1d89c524 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -9136,6 +9136,14 @@ This does NOT work: >
 			variables are automatically deleted when the function
 			ends.
 
+:unl[et] ${env-name} ...			*:unlet-environment* *:unlet-$*
+			Remove environment variable {env-name}.
+			Can mix {name} and ${env-name} in one :unlet command.
+			No error message is given for a non-existing
+			variable, also without !.
+			If the system does not support deleting an environment
+			variable, it is made emtpy.
+
 :lockv[ar][!] [depth] {name} ...			*:lockvar* *:lockv*
 			Lock the internal variable {name}.  Locking means that
 			it can no longer be changed (until it is unlocked).
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 41a9eeeb40..2aab2d72a7 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -2818,6 +2818,18 @@ static void ex_unletlock(exarg_T *eap, char_u *argstart, int deep)
   lval_T lv;
 
   do {
+    if (*arg == '$') {
+      const char *name = (char *)++arg;
+
+      if (get_env_len((const char_u **)&arg) == 0) {
+        EMSG2(_(e_invarg2), name - 1);
+        return;
+      }
+      os_unsetenv(name);
+      arg = skipwhite(arg);
+      continue;
+    }
+
     // Parse the name and find the end.
     char_u *const name_end = (char_u *)get_lval(arg, NULL, &lv, true,
                                                 eap->skip || error,
diff --git a/src/nvim/testdir/test_unlet.vim b/src/nvim/testdir/test_unlet.vim
index 3f06058d03..dbddffb492 100644
--- a/src/nvim/testdir/test_unlet.vim
+++ b/src/nvim/testdir/test_unlet.vim
@@ -28,3 +28,27 @@ endfunc
 func Test_unlet_fails()
   call assert_fails('unlet v:["count"]', 'E46:')
 endfunc
+
+func Test_unlet_env()
+  let envcmd = has('win32') ? 'set' : 'env'
+
+  let $FOOBAR = 'test'
+  let found = 0
+  for kv in split(system(envcmd), "\r*\n")
+    if kv == 'FOOBAR=test'
+      let found = 1
+    endif
+  endfor
+  call assert_equal(1, found)
+
+  unlet $FOOBAR
+  let found = 0
+  for kv in split(system(envcmd), "\r*\n")
+    if kv == 'FOOBAR=test'
+      let found = 1
+    endif
+  endfor
+  call assert_equal(0, found)
+
+  unlet $MUST_NOT_BE_AN_ERROR
+endfunc
-- 
cgit 


From c0d835764fbf33b2effc359498e58e8a114444a8 Mon Sep 17 00:00:00 2001
From: Jan Edmund Lazo <janedmundlazo@hotmail.com>
Date: Tue, 2 Oct 2018 22:10:47 -0400
Subject: vim-patch:8.1.0047: no completion for :unlet $VAR

Problem:    No completion for :unlet $VAR.
Solution:   Add completion. (Jason Franklin)
https://github.com/vim/vim/commit/19834010889fc5bfa0f88b3ba83133dae6c0a35d
---
 src/nvim/ex_docmd.c             | 13 +++++++++++--
 src/nvim/testdir/test_unlet.vim | 10 ++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index f8d4e7d980..2a733f5831 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -3260,8 +3260,15 @@ const char * set_one_cmd_context(
     while ((xp->xp_pattern = (char_u *)strchr(arg, ' ')) != NULL) {
       arg = (const char *)xp->xp_pattern + 1;
     }
+
     xp->xp_context = EXPAND_USER_VARS;
     xp->xp_pattern = (char_u *)arg;
+
+    if (*xp->xp_pattern == '$') {
+      xp->xp_context = EXPAND_ENV_VARS;
+      xp->xp_pattern++;
+    }
+
     break;
 
   case CMD_function:
@@ -9049,8 +9056,10 @@ makeopens(
     // cursor can be set.  This is done again below.
     // winminheight and winminwidth need to be set to avoid an error if the
     // user has set winheight or winwidth.
-    if (put_line(fd, "set winminheight=1 winminwidth=1 winheight=1 winwidth=1")
-        == FAIL) {
+    if (put_line(fd, "set winminheight=0") == FAIL
+        || put_line(fd, "set winheight=1") == FAIL
+        || put_line(fd, "set winminwidth=0") == FAIL
+        || put_line(fd, "set winwidth=1") == FAIL) {
       return FAIL;
     }
     if (nr > 1 && ses_winsizes(fd, restore_size, tab_firstwin) == FAIL) {
diff --git a/src/nvim/testdir/test_unlet.vim b/src/nvim/testdir/test_unlet.vim
index dbddffb492..b02bdaab3b 100644
--- a/src/nvim/testdir/test_unlet.vim
+++ b/src/nvim/testdir/test_unlet.vim
@@ -52,3 +52,13 @@ func Test_unlet_env()
 
   unlet $MUST_NOT_BE_AN_ERROR
 endfunc
+
+func Test_unlet_complete()
+  let g:FOOBAR = 1
+  call feedkeys(":unlet g:FOO\t\n", 'tx')
+  call assert_true(!exists('g:FOOBAR'))
+
+  let $FOOBAR = 1
+  call feedkeys(":unlet $FOO\t\n", 'tx')
+  call assert_true(!exists('$FOOBAR') || empty($FOOBAR))
+endfunc
-- 
cgit