Parallelize some tests

zapcore/level_test.go

@@ -239,7 +239,10 @@ func TestLevelOf(t *testing.T) {
 	}
 
 	for _, tt := range tests {
+		tt := tt
 		t.Run(tt.desc, func(t *testing.T) {
+			t.Parallel()
+
 			assert.Equal(t, tt.want, LevelOf(tt.give), "Reported level did not match.")
 		})
 	}

zapcore/sampler_test.go

@@ -91,7 +91,10 @@ func TestSampler(t *testing.T) {
 func TestLevelOfSampler(t *testing.T) {
 	levels := []Level{DebugLevel, InfoLevel, WarnLevel, ErrorLevel, DPanicLevel, PanicLevel, FatalLevel}
 	for _, lvl := range levels {
+		lvl := lvl
 		t.Run(lvl.String(), func(t *testing.T) {
+			t.Parallel()
+
 			sampler, _ := fakeSampler(lvl, time.Minute, 2, 3)
 			assert.Equal(t, lvl, LevelOf(sampler), "Sampler level did not match.")
 		})

zapcore/tee_test.go

@@ -77,7 +77,10 @@ func TestLevelOfTee(t *testing.T) {
 	}
 
 	for _, tt := range tests {
+		tt := tt
 		t.Run(tt.desc, func(t *testing.T) {
+			t.Parallel()
+
 			core := NewTee(tt.give...)
 			assert.Equal(t, tt.want, LevelOf(core), "Level of Tee core did not match.")
 		})