patch 8.2.1387: Vim9: cannot assign to single letter variable with typev8.2.1387

Problem:    Vim9: cannot assign to single letter variable with type.
Solution:   Exclude the colon from the variable name. (closes #6647)

3 files changed, 28 insertions, 6 deletions

diff --git a/src/eval.c b/src/eval.c
index 877b3bc0f..c695468cd 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -820,14 +820,23 @@ get_lval(
     {
 	lp->ll_name = name;
 
-	if (in_vim9script() && *p == ':')
+	if (in_vim9script())
 	{
-	    scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
-	    char_u	 *tp = skipwhite(p + 1);
+	    // "a: type" is declaring variable "a" with a type, not "a:".
+	    if (p == name + 2 && p[-1] == ':')
+	    {
+		--p;
+		lp->ll_name_end = p;
+	    }
+	    if (*p == ':')
+	    {
+		scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
+		char_u	 *tp = skipwhite(p + 1);
 
-	    // parse the type after the name
-	    lp->ll_type = parse_type(&tp, &si->sn_type_list);
-	    lp->ll_name_end = tp;
+		// parse the type after the name
+		lp->ll_type = parse_type(&tp, &si->sn_type_list);
+		lp->ll_name_end = tp;
+	    }
 	}
     }
 
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index e5d5e872d..ba18af09e 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -449,6 +449,17 @@ def Test_assignment_vim9script()
       @+ = 'plus'
       assert_equal('plus', @+)
     endif
+
+    let a: number = 123
+    assert_equal(123, a)
+    let s: string = 'yes'
+    assert_equal('yes', s)
+    let b: number = 42
+    assert_equal(42, b)
+    let w: number = 43
+    assert_equal(43, w)
+    let t: number = 44
+    assert_equal(44, t)
   END
   CheckScriptSuccess(lines)
 enddef
diff --git a/src/version.c b/src/version.c
index e251ba865..11b686255 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1387,
+/**/
     1386,
 /**/
     1385,