addressing comments

comp/logs/agent/config/integration_config.go

@@ -112,6 +112,8 @@ func (t *StringSliceField) UnmarshalYAML(unmarshal func(interface{}) error) erro
 		for _, item := range raw {
 			if str, ok := item.(string); ok {
 				*t = append(*t, str)
+			} else {
+				return fmt.Errorf("cannot unmarshal %v into a string", item)
 			}
 		}
 		return nil

comp/logs/agent/config/parser_test.go

@@ -64,12 +64,15 @@ foo:
 `, `
 - type: file
   path: /var/log/app.log
-  tags: a, b:c
+  tags: nil
 `, `
 `}
 
-	for _, format := range invalidFormats {
-		configs, _ := ParseYAML([]byte(format))
+	for i, format := range invalidFormats {
+		configs, err := ParseYAML([]byte(format))
+		if i == 1 {
+			assert.NotNil(t, err)
+		}
 		require.Equal(t, 0, len(configs))
 	}
 }

pkg/logs/launchers/container/tailerfactory/file_test.go

@@ -14,7 +14,6 @@ import (
 	"runtime"
 	"testing"
 
-	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/fx"
 
@@ -24,7 +23,7 @@ import (
 	workloadmeta "github.com/DataDog/datadog-agent/comp/core/workloadmeta/def"
 	workloadmetafxmock "github.com/DataDog/datadog-agent/comp/core/workloadmeta/fx-mock"
 	workloadmetamock "github.com/DataDog/datadog-agent/comp/core/workloadmeta/mock"
-	config "github.com/DataDog/datadog-agent/comp/logs/agent/config"
+	"github.com/DataDog/datadog-agent/comp/logs/agent/config"
 	configmock "github.com/DataDog/datadog-agent/pkg/config/mock"
 	"github.com/DataDog/datadog-agent/pkg/logs/internal/util/containersorpods"
 	"github.com/DataDog/datadog-agent/pkg/logs/pipeline"
@@ -318,7 +317,7 @@ func TestMakeK8sSource(t *testing.T) {
 			require.Equal(t, wildcard, child.Config.Path)
 			require.Equal(t, "src", child.Config.Source)
 			require.Equal(t, "svc", child.Config.Service)
-			assert.EqualValues(t, config.StringSliceField{"tag!"}, child.Config.Tags)
+			require.Equal(t, []string{"tag!"}, []string(child.Config.Tags))
 			require.Equal(t, *child.Config.AutoMultiLine, true)
 			require.Equal(t, child.Config.AutoMultiLineSampleSize, 123)
 			require.Equal(t, child.Config.AutoMultiLineMatchThreshold, 0.123)

pkg/logs/schedulers/channel/scheduler_test.go

@@ -39,5 +39,5 @@ func TestScheduler(t *testing.T) {
 
 	require.Equal(t, len(spy.Events), 1) // no change
 	assert.Nil(t, source.Config.Tags)
-	assert.Equal(t, config.StringSliceField{"foo"}, source.Config.ChannelTags)
+	assert.Equal(t, []string{"foo"}, []string(source.Config.ChannelTags))
 }