From d7285430f23e512ef2bfc2965c4f9fe6563108c7 Mon Sep 17 00:00:00 2001
From: Nathan Rijksen <n.rijksen@gmail.com>
Date: Wed, 13 Sep 2023 10:22:50 -0700
Subject: [PATCH] Fix EOF not triggering a clean of the final output

---
 outputproducer.go      |  3 +++
 outputproducer_test.go | 15 +++++++++++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/outputproducer.go b/outputproducer.go
index fa98338..3f91138 100644
--- a/outputproducer.go
+++ b/outputproducer.go
@@ -86,6 +86,9 @@ func (o *outputProducer) processNextRead(r io.Reader, w io.Writer, appendBuffer
 		if _, err := w.Write(snapshot[:n]); err != nil {
 			return fmt.Errorf("could not write: %w", err)
 		}
+	}
+
+	if n > 0 || isEOF {
 		if err := appendBuffer(snapshot[:n], isEOF); err != nil {
 			return fmt.Errorf("could not append buffer: %w", err)
 		}
diff --git a/outputproducer_test.go b/outputproducer_test.go
index 46c0bad..5d2775e 100644
--- a/outputproducer_test.go
+++ b/outputproducer_test.go
@@ -37,7 +37,7 @@ func Test_outputProducer_listen(t *testing.T) {
 					{[]byte("Three"), chunkInterval},
 				},
 			},
-			[]string{"One", "Two", "Three"},
+			[]string{"One", "Two", "Three", ""}, // Last append is EOF and should ALWAYS happen
 			nil,
 		},
 		{
@@ -48,7 +48,18 @@ func Test_outputProducer_listen(t *testing.T) {
 					{[]byte(valExceedBuff), chunkInterval},
 				},
 			},
-			[]string{valExceedBuff[:bufferSize], valExceedBuff[bufferSize:]},
+			[]string{valExceedBuff[:bufferSize], valExceedBuff[bufferSize:], ""}, // Last append is EOF and should ALWAYS happen
+			nil,
+		},
+		{
+			"EOF should trigger an append, even if new output is empty",
+			func(t *testing.T) *outputProducer { return newOutputProducer(newTestOpts(nil, t)) },
+			&readTester{
+				[]readTesterChunk{
+					{[]byte("foo"), chunkInterval},
+				},
+			},
+			[]string{"foo", ""},
 			nil,
 		},
 	}