vim-patch:8.1.1683: dictionary with string keys is longer than needed

Problem:    Dictionary with string keys is longer than needed.
Solution:   Use *{key: val} for literaly keys.
d5abb4c877

Vim's popup,textprop features are N/A.
Neovim has not polyfilled their APIs.
Skip docs and tests for these features.

runtime/doc/eval.txt

@@ -38,7 +38,9 @@ List		An ordered sequence of items |List|.
 
 Dictionary	An associative, unordered array: Each entry has a key and a
 		value. |Dictionary|
-		Example: {'blue': "#0000ff", 'red': "#ff0000"}
+		Examples:
+			{'blue': "#0000ff", 'red': "#ff0000"}
+			*{blue: "#0000ff", red: "#ff0000"}
 
 The Number and String types are converted automatically, depending on how they
 are used.
@@ -436,8 +438,14 @@ only appear once.  Examples: >
 A key is always a String.  You can use a Number, it will be converted to a
 String automatically.  Thus the String '4' and the number 4 will find the same
 entry.  Note that the String '04' and the Number 04 are different, since the
-Number will be converted to the String '4'.  The empty string can be used as a
-key.
+Number will be converted to the String '4'.  The empty string can also be used
+as a key.
+						*literal-Dict*
+To avoid having to put quotes around every key the *{} form can be used.  This
+does require the key to consist only of ASCII letters, digits, '-' and '_'.
+Example: >
+	let mydict = *{zero: 0, one_key: 1, two-key: 2, 333: 3}
+Note that 333 here is the string "333".  Empty keys are not possible here.
 
 A value can be any expression.  Using a Dictionary for a value creates a
 nested Dictionary: >

src/nvim/eval.c

@@ -3905,6 +3905,7 @@ static int eval6(char_u **arg, typval_T *rettv, int evaluate, int want_string)
 //  (expression) nested expression
 //  [expr, expr] List
 //  {key: val, key: val}  Dictionary
+//  *{key: val, key: val}  Dictionary with literal keys
 //
 //  Also handle:
 //  ! in front  logical NOT
@@ -4012,11 +4013,21 @@ static int eval7(
   case '[':   ret = get_list_tv(arg, rettv, evaluate);
     break;
 
+  // Dictionary: *{key: val, key: val}
+  case '*':
+    if ((*arg)[1] == '{') {
+      (*arg)++;
+      ret = dict_get_tv(arg, rettv, evaluate, true);
+    } else {
+      ret = NOTDONE;
+    }
+    break;
+
   // Lambda: {arg, arg -> expr}
-  // Dictionary: {key: val, key: val}
+  // Dictionary: {'key': val, 'key': val}
   case '{':   ret = get_lambda_tv(arg, rettv, evaluate);
               if (ret == NOTDONE) {
-                ret = dict_get_tv(arg, rettv, evaluate);
+                ret = dict_get_tv(arg, rettv, evaluate, false);
               }
     break;
 
@@ -5347,11 +5358,31 @@ static inline bool set_ref_dict(dict_T *dict, int copyID)
   return false;
 }
 
-/*
- * Allocate a variable for a Dictionary and fill it from "*arg".
- * Return OK or FAIL.  Returns NOTDONE for {expr}.
- */
-static int dict_get_tv(char_u **arg, typval_T *rettv, int evaluate)
+
+// Get the key for *{key: val} into "tv" and advance "arg".
+// Return FAIL when there is no valid key.
+static int get_literal_key(char_u **arg, typval_T *tv)
+  FUNC_ATTR_NONNULL_ALL
+{
+  char_u *p;
+
+  if (!ASCII_ISALNUM(**arg) && **arg != '_' && **arg != '-') {
+    return FAIL;
+  }
+  for (p = *arg; ASCII_ISALNUM(*p) || *p == '_' || *p == '-'; p++) {
+  }
+  tv->v_type = VAR_STRING;
+  tv->vval.v_string = vim_strnsave(*arg, (int)(p - *arg));
+
+  *arg = skipwhite(p);
+  return OK;
+}
+
+// Allocate a variable for a Dictionary and fill it from "*arg".
+// "literal" is true for *{key: val}
+// Return OK or FAIL.  Returns NOTDONE for {expr}.
+static int dict_get_tv(char_u **arg, typval_T *rettv, int evaluate,
+                       bool literal)
 {
   dict_T      *d = NULL;
   typval_T tvkey;
@@ -5385,7 +5416,9 @@ static int dict_get_tv(char_u **arg, typval_T *rettv, int evaluate)
 
   *arg = skipwhite(*arg + 1);
   while (**arg != '}' && **arg != NUL) {
-    if (eval1(arg, &tvkey, evaluate) == FAIL) {         // recursive!
+    if ((literal
+         ? get_literal_key(arg, &tvkey)
+         : eval1(arg, &tvkey, evaluate)) == FAIL) {  // recursive!
       goto failret;
     }
     if (**arg != ':') {

src/nvim/testdir/test_listdict.vim

@@ -280,6 +280,10 @@ func Test_dict_func_remove_in_use()
   call assert_equal(expected, d.func(string(remove(d, 'func'))))
 endfunc
 
+func Test_dict_literal_keys()
+  call assert_equal({'one': 1, 'two2': 2, '3three': 3, '44': 4}, *{one: 1, two2: 2, 3three: 3, 44: 4},)
+endfunc
+
 " Nasty: deepcopy() dict that refers to itself (fails when noref used)
 func Test_dict_deepcopy()
   let d = {1:1, 2:2}