Upgraded feedkit's handling of stream sources

sources/stream_errors_test.go

@@ -0,0 +1,52 @@
+package sources
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+)
+
+func TestStreamRetryableWrapsThroughErrorChains(t *testing.T) {
+	base := errors.New("retry me")
+	err := fmt.Errorf("outer: %w", StreamRetryable(base))
+
+	if !IsStreamRetryable(err) {
+		t.Fatalf("IsStreamRetryable() = false, want true")
+	}
+	if IsStreamFatal(err) {
+		t.Fatalf("IsStreamFatal() = true, want false")
+	}
+	if !errors.Is(err, base) {
+		t.Fatalf("errors.Is(err, base) = false, want true")
+	}
+}
+
+func TestStreamFatalWrapsThroughErrorChains(t *testing.T) {
+	base := errors.New("fatal")
+	err := fmt.Errorf("outer: %w", StreamFatal(base))
+
+	if !IsStreamFatal(err) {
+		t.Fatalf("IsStreamFatal() = false, want true")
+	}
+	if IsStreamRetryable(err) {
+		t.Fatalf("IsStreamRetryable() = true, want false")
+	}
+	if !errors.Is(err, base) {
+		t.Fatalf("errors.Is(err, base) = false, want true")
+	}
+}
+
+func TestStreamErrorHelpersNil(t *testing.T) {
+	if StreamRetryable(nil) != nil {
+		t.Fatalf("StreamRetryable(nil) != nil")
+	}
+	if StreamFatal(nil) != nil {
+		t.Fatalf("StreamFatal(nil) != nil")
+	}
+	if IsStreamRetryable(nil) {
+		t.Fatalf("IsStreamRetryable(nil) = true")
+	}
+	if IsStreamFatal(nil) {
+		t.Fatalf("IsStreamFatal(nil) = true")
+	}
+}