vim-patch:8.0.1389: getqflist() items are missing if not set

Problem:    getqflist() items are missing if not set, that makes it more
            difficult to handle the values.
Solution:   When a value is not available return zero or another invalid
            value. (Yegappan Lakshmanan)

https://github.com/vim/vim/commit/a6d4849c711379b773529afaed640455287ac934

2 files changed, 144 insertions, 58 deletions

diff --git a/src/nvim/quickfix.c b/src/nvim/quickfix.c
index f086621df8..76b82ea5bc 100644
--- a/src/nvim/quickfix.c
+++ b/src/nvim/quickfix.c
@@ -4269,69 +4269,27 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
   if (wp != NULL) {
     qi = GET_LOC_LIST(wp);
   }
-  // List is not present or is empty
-  if (qi == NULL || qi->qf_listcount == 0) {
-    // If querying for the size of the list, return 0
-    if (((di = tv_dict_find(what, S_LEN("nr"))) != NULL)
-        && (di->di_tv.v_type == VAR_STRING)
-        && (STRCMP(di->di_tv.vval.v_string, "$") == 0)) {
-      return tv_dict_add_nr(retdict, S_LEN("nr"), 0);
-    }
-    return FAIL;
-  }
 
-  int status = OK;
   int flags = QF_GETLIST_NONE;
 
-  int qf_idx = qi->qf_curlist;  // default is the current list
-  if ((di = tv_dict_find(what, S_LEN("nr"))) != NULL) {
-    // Use the specified quickfix/location list
-    if (di->di_tv.v_type == VAR_NUMBER) {
-      // for zero use the current list
-      if (di->di_tv.vval.v_number != 0) {
-        qf_idx = (int)di->di_tv.vval.v_number - 1;
-        if (qf_idx < 0 || qf_idx >= qi->qf_listcount) {
-          return FAIL;
-        }
-      }
-    } else if (di->di_tv.v_type == VAR_STRING
-               && strequal((const char *)di->di_tv.vval.v_string, "$")) {
-      // Get the last quickfix list number
-      qf_idx = qi->qf_listcount - 1;
-    } else {
-      return FAIL;
-    }
-    flags |= QF_GETLIST_NR;
-  }
-
-  if ((di = tv_dict_find(what, S_LEN("id"))) != NULL) {
-    // Look for a list with the specified id
-    if (di->di_tv.v_type == VAR_NUMBER) {
-      // For zero, use the current list or the list specifed by 'nr'
-      if (di->di_tv.vval.v_number != 0) {
-        qf_idx = qf_id2nr(qi, (unsigned)di->di_tv.vval.v_number);
-        if (qf_idx == -1) {
-          return FAIL;      // List not found
-        }
-      }
-      flags |= QF_GETLIST_ID;
-    } else {
-      return FAIL;
-    }
-  }
-
   if (tv_dict_find(what, S_LEN("all")) != NULL) {
     flags |= QF_GETLIST_ALL;
   }
   if (tv_dict_find(what, S_LEN("title")) != NULL) {
     flags |= QF_GETLIST_TITLE;
   }
+  if (tv_dict_find(what, S_LEN("nr")) != NULL) {
+    flags |= QF_GETLIST_NR;
+  }
   if (tv_dict_find(what, S_LEN("winid")) != NULL) {
     flags |= QF_GETLIST_WINID;
   }
   if (tv_dict_find(what, S_LEN("context")) != NULL) {
     flags |= QF_GETLIST_CONTEXT;
   }
+  if (tv_dict_find(what, S_LEN("id")) != NULL) {
+    flags |= QF_GETLIST_ID;
+  }
   if (tv_dict_find(what, S_LEN("items")) != NULL) {
     flags |= QF_GETLIST_ITEMS;
   }
@@ -4342,6 +4300,75 @@ int qf_get_properties(win_T *wp, dict_T *what, dict_T *retdict)
     flags |= QF_GETLIST_SIZE;
   }
 
+  int qf_idx;
+
+  if (qi != NULL && qi->qf_listcount != 0) {
+    qf_idx = qi->qf_curlist;  // default is the current list
+    if ((di = tv_dict_find(what, S_LEN("nr"))) != NULL) {
+      // Use the specified quickfix/location list
+      if (di->di_tv.v_type == VAR_NUMBER) {
+        // for zero use the current list
+        if (di->di_tv.vval.v_number != 0) {
+          qf_idx = (int)di->di_tv.vval.v_number - 1;
+          if (qf_idx < 0 || qf_idx >= qi->qf_listcount) {
+            qf_idx = -1;
+          }
+        }
+      } else if (di->di_tv.v_type == VAR_STRING
+                 && strequal((const char *)di->di_tv.vval.v_string, "$")) {
+        // Get the last quickfix list number
+        qf_idx = qi->qf_listcount - 1;
+      } else {
+        qf_idx = -1;
+      }
+      flags |= QF_GETLIST_NR;
+    }
+
+    if ((di = tv_dict_find(what, S_LEN("id"))) != NULL) {
+      // Look for a list with the specified id
+      if (di->di_tv.v_type == VAR_NUMBER) {
+        // For zero, use the current list or the list specifed by 'nr'
+        if (di->di_tv.vval.v_number != 0) {
+          qf_idx = qf_id2nr(qi, (unsigned)di->di_tv.vval.v_number);
+        }
+        flags |= QF_GETLIST_ID;
+      } else {
+        qf_idx = -1;
+      }
+    }
+  }
+
+  int status = OK;
+
+  // List is not present or is empty
+  if (qi == NULL || qi->qf_listcount == 0 || qf_idx == -1) {
+    if (flags & QF_GETLIST_TITLE) {
+      status = tv_dict_add_str(retdict, S_LEN("title"), (const char *)"");
+    }
+    if ((status == OK) && (flags & QF_GETLIST_ITEMS)) {
+      list_T *l = tv_list_alloc(kListLenMayKnow);
+      status = tv_dict_add_list(retdict, S_LEN("items"), l);
+    }
+    if ((status == OK) && (flags & QF_GETLIST_NR)) {
+      status = tv_dict_add_nr(retdict, S_LEN("nr"), 0);
+    }
+    if ((status == OK) && (flags & QF_GETLIST_WINID)) {
+      status = tv_dict_add_nr(retdict, S_LEN("winid"), 0);
+    }
+    if ((status == OK) && (flags & QF_GETLIST_CONTEXT)) {
+      status = tv_dict_add_str(retdict, S_LEN("context"), (const char *)"");
+    }
+    if ((status == OK) && (flags & QF_GETLIST_ID)) {
+      status = tv_dict_add_nr(retdict, S_LEN("id"), 0);
+    }
+    if ((status == OK) && (flags & QF_GETLIST_IDX)) {
+      status = tv_dict_add_nr(retdict, S_LEN("idx"), 0);
+    }
+    if ((status == OK) && (flags & QF_GETLIST_SIZE)) {
+      status = tv_dict_add_nr(retdict, S_LEN("size"), 0);
+    }
+    return status;
+  }
 
   if (flags & QF_GETLIST_TITLE) {
     char_u *t = qi->qf_lists[qf_idx].qf_title;
diff --git a/src/nvim/testdir/test_quickfix.vim b/src/nvim/testdir/test_quickfix.vim
index 0ddc0ab76e..67e7cc469b 100644
--- a/src/nvim/testdir/test_quickfix.vim
+++ b/src/nvim/testdir/test_quickfix.vim
@@ -1784,8 +1784,8 @@ func Xproperty_tests(cchar)
     call assert_equal(-1, s)
 
     call assert_equal({}, g:Xgetlist({'abc':1}))
-    call assert_equal({}, g:Xgetlist({'nr':99, 'title':1}))
-    call assert_equal({}, g:Xgetlist({'nr':[], 'title':1}))
+    call assert_equal('', g:Xgetlist({'nr':99, 'title':1}).title)
+    call assert_equal('', g:Xgetlist({'nr':[], 'title':1}).title)
 
     if a:cchar == 'l'
 	call assert_equal({}, getloclist(99, {'title': 1}))
@@ -1821,7 +1821,7 @@ func Xproperty_tests(cchar)
 	call assert_equal([1, 2], getloclist(w2_id, {'context':1}).context)
 	only
 	call setloclist(0, [], 'f')
-	call assert_equal({}, getloclist(0, {'context':1}))
+	call assert_equal('', getloclist(0, {'context':1}).context)
     endif
 
     " Test for changing the context of previous quickfix lists
@@ -2335,8 +2335,8 @@ func XsizeTests(cchar)
 
   call g:Xsetlist([], 'f')
   call assert_equal(0, g:Xgetlist({'nr':'$'}).nr)
-  call assert_equal(1, len(g:Xgetlist({'nr':'$', 'all':1})))
-  call assert_equal(0, len(g:Xgetlist({'nr':0})))
+  call assert_equal('', g:Xgetlist({'nr':'$', 'all':1}).title)
+  call assert_equal(0, g:Xgetlist({'nr':0}).nr)
 
   Xexpr "File1:10:Line1"
   Xexpr "File2:20:Line2"
@@ -2735,7 +2735,7 @@ func Xqfid_tests(cchar)
   call s:setup_commands(a:cchar)
 
   call g:Xsetlist([], 'f')
-  call assert_equal({}, g:Xgetlist({'id':0}))
+  call assert_equal(0, g:Xgetlist({'id':0}).id)
   Xexpr ''
   let start_id = g:Xgetlist({'id' : 0}).id
   Xexpr '' | Xexpr ''
@@ -2743,10 +2743,10 @@ func Xqfid_tests(cchar)
   call assert_equal(start_id, g:Xgetlist({'id':0, 'nr':1}).id)
   call assert_equal(start_id + 1, g:Xgetlist({'id':0, 'nr':0}).id)
   call assert_equal(start_id + 2, g:Xgetlist({'id':0, 'nr':'$'}).id)
-  call assert_equal({}, g:Xgetlist({'id':0, 'nr':99}))
+  call assert_equal(0, g:Xgetlist({'id':0, 'nr':99}).id)
   call assert_equal(2, g:Xgetlist({'id':start_id + 1, 'nr':0}).nr)
-  call assert_equal({}, g:Xgetlist({'id':99, 'nr':0}))
-  call assert_equal({}, g:Xgetlist({'id':"abc", 'nr':0}))
+  call assert_equal(0, g:Xgetlist({'id':99, 'nr':0}).id)
+  call assert_equal(0, g:Xgetlist({'id':"abc", 'nr':0}).id)
 
   call g:Xsetlist([], 'a', {'id':start_id, 'context':[1,2]})
   call assert_equal([1,2], g:Xgetlist({'nr':1, 'context':1}).context)
@@ -2757,7 +2757,7 @@ func Xqfid_tests(cchar)
 
   let qfid = g:Xgetlist({'id':0, 'nr':0})
   call g:Xsetlist([], 'f')
-  call assert_equal({}, g:Xgetlist({'id':qfid, 'nr':0}))
+  call assert_equal(0, g:Xgetlist({'id':qfid, 'nr':0}).id)
 endfunc
 
 func Test_qf_id()
@@ -2838,3 +2838,62 @@ func Test_empty_qfbuf()
   enew
   call delete('Xfile1')
 endfunc
+
+" Tests for the getqflist() and getloclist() functions when the list is not
+" present or is empty
+func Xgetlist_empty_tests(cchar)
+  call s:setup_commands(a:cchar)
+
+  " Empty quickfix stack
+  call g:Xsetlist([], 'f')
+  call assert_equal('', g:Xgetlist({'context' : 0}).context)
+  call assert_equal(0, g:Xgetlist({'id' : 0}).id)
+  call assert_equal(0, g:Xgetlist({'idx' : 0}).idx)
+  call assert_equal([], g:Xgetlist({'items' : 0}).items)
+  call assert_equal(0, g:Xgetlist({'nr' : 0}).nr)
+  call assert_equal(0, g:Xgetlist({'size' : 0}).size)
+  call assert_equal('', g:Xgetlist({'title' : 0}).title)
+  call assert_equal(0, g:Xgetlist({'winid' : 0}).winid)
+  call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [], 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0}, g:Xgetlist({'all' : 0}))
+
+  " Empty quickfix list
+  Xexpr ""
+  call assert_equal('', g:Xgetlist({'context' : 0}).context)
+  call assert_notequal(0, g:Xgetlist({'id' : 0}).id)
+  call assert_equal(0, g:Xgetlist({'idx' : 0}).idx)
+  call assert_equal([], g:Xgetlist({'items' : 0}).items)
+  call assert_notequal(0, g:Xgetlist({'nr' : 0}).nr)
+  call assert_equal(0, g:Xgetlist({'size' : 0}).size)
+  call assert_notequal('', g:Xgetlist({'title' : 0}).title)
+  call assert_equal(0, g:Xgetlist({'winid' : 0}).winid)
+
+  let qfid = g:Xgetlist({'id' : 0}).id
+  call g:Xsetlist([], 'f')
+
+  " Non-existing quickfix identifier
+  call assert_equal('', g:Xgetlist({'id' : qfid, 'context' : 0}).context)
+  call assert_equal(0, g:Xgetlist({'id' : qfid}).id)
+  call assert_equal(0, g:Xgetlist({'id' : qfid, 'idx' : 0}).idx)
+  call assert_equal([], g:Xgetlist({'id' : qfid, 'items' : 0}).items)
+  call assert_equal(0, g:Xgetlist({'id' : qfid, 'nr' : 0}).nr)
+  call assert_equal(0, g:Xgetlist({'id' : qfid, 'size' : 0}).size)
+  call assert_equal('', g:Xgetlist({'id' : qfid, 'title' : 0}).title)
+  call assert_equal(0, g:Xgetlist({'id' : qfid, 'winid' : 0}).winid)
+  call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [], 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0}, g:Xgetlist({'id' : qfid, 'all' : 0}))
+
+  " Non-existing quickfix list number
+  call assert_equal('', g:Xgetlist({'nr' : 5, 'context' : 0}).context)
+  call assert_equal(0, g:Xgetlist({'nr' : 5}).nr)
+  call assert_equal(0, g:Xgetlist({'nr' : 5, 'idx' : 0}).idx)
+  call assert_equal([], g:Xgetlist({'nr' : 5, 'items' : 0}).items)
+  call assert_equal(0, g:Xgetlist({'nr' : 5, 'id' : 0}).id)
+  call assert_equal(0, g:Xgetlist({'nr' : 5, 'size' : 0}).size)
+  call assert_equal('', g:Xgetlist({'nr' : 5, 'title' : 0}).title)
+  call assert_equal(0, g:Xgetlist({'nr' : 5, 'winid' : 0}).winid)
+  call assert_equal({'context' : '', 'id' : 0, 'idx' : 0, 'items' : [], 'nr' : 0, 'size' : 0, 'title' : '', 'winid' : 0}, g:Xgetlist({'nr' : 5, 'all' : 0}))
+endfunc
+
+func Test_getqflist()
+  call Xgetlist_empty_tests('c')
+  call Xgetlist_empty_tests('l')
+endfunc