eval: Make setmatches() return -1 in case of some failures

2 files changed, 9 insertions, 3 deletions

diff --git a/test/functional/eval/match_functions_spec.lua b/test/functional/eval/match_functions_spec.lua
index df91e41475..f6bad59c66 100644
--- a/test/functional/eval/match_functions_spec.lua
+++ b/test/functional/eval/match_functions_spec.lua
@@ -36,4 +36,11 @@ describe('setmatches()', function()
       conceal='5',
     }}, funcs.getmatches())
   end)
+
+  it('fails with -1 if highlight group is not defined', function()
+    eq(-1, funcs.setmatches({{group=1, pattern=2, id=3, priority=4}}))
+    eq({}, funcs.getmatches())
+    eq(-1, funcs.setmatches({{group=1, pos1={2}, pos2={6}, id=3, priority=4, conceal=5}}))
+    eq({}, funcs.getmatches())
+  end)
 end)
diff --git a/test/functional/legacy/063_match_and_matchadd_spec.lua b/test/functional/legacy/063_match_and_matchadd_spec.lua
index 298e0a31ea..5818bb6b3a 100644
--- a/test/functional/legacy/063_match_and_matchadd_spec.lua
+++ b/test/functional/legacy/063_match_and_matchadd_spec.lua
@@ -97,11 +97,10 @@ describe('063: Test for ":match", "matchadd()" and related functions', function(
 
     -- Check that "setmatches()" will not add two matches with the same ID. The
     -- expected behaviour (for now) is to add the first match but not the
-    -- second and to return 0 (even though it is a matter of debate whether
-    -- this can be considered successful behaviour).
+    -- second and to return -1.
     execute("let r1 = setmatches([{'group': 'MyGroup1', 'pattern': 'TODO', 'priority': 10, 'id': 1}, {'group': 'MyGroup2', 'pattern': 'FIXME', 'priority': 10, 'id': 1}])")
     feed("<cr>")
-    eq(0, eval("r1"))
+    eq(-1, eval("r1"))
     eq({{group = 'MyGroup1', pattern = 'TODO', priority = 10, id = 1}}, eval('getmatches()'))
 
     -- Check that "setmatches()" returns 0 if successful and otherwise -1.