Fix bug in EmailSectionExtractor when text ends with an empty line

k9mail/src/main/java/com/fsck/k9/message/html/EmailSectionExtractor.kt

@@ -96,12 +96,10 @@ class EmailSectionExtractor private constructor(val text: String) {
     }
 
     private fun completeLastSection() {
-        if (!isStartOfLine) {
-            if (quoteDepth == 0) {
-                sectionBuilder.addSegment(0, sectionStartIndex, text.length)
-            } else {
-                sectionBuilder.addSegment(spaces, startOfContentIndex, text.length)
-            }
+        if (quoteDepth == 0) {
+            sectionBuilder.addSegment(0, sectionStartIndex, text.length)
+        } else if (!isStartOfLine) {
+            sectionBuilder.addSegment(spaces, startOfContentIndex, text.length)
         }
 
         appendSection()

k9mail/src/test/java/com/fsck/k9/message/html/EmailSectionExtractorTest.kt

@@ -26,6 +26,19 @@ class EmailSectionExtractorTest {
         }
     }
 
+    @Test
+    fun simpleMessageEndingWithTwoNewlines() {
+        val message = "Hello\n\n"
+
+        val sections = EmailSectionExtractor.extract(message)
+
+        assertThat(sections.size).isEqualTo(1)
+        with(sections[0]) {
+            assertThat(quoteDepth).isEqualTo(0)
+            assertThat(toString()).isEqualTo(message)
+        }
+    }
+
     @Test
     fun quoteFollowedByReply() {
         val message = """
@@ -81,6 +94,24 @@ class EmailSectionExtractorTest {
         }
     }
 
+    @Test
+    fun quoteEndingWithEmptyLineButNoNewline() {
+        val message = """
+            > Quoted text
+            > """.trimIndent()
+
+        val sections = EmailSectionExtractor.extract(message)
+
+        assertThat(sections.size).isEqualTo(1)
+        with(sections[0]) {
+            assertThat(quoteDepth).isEqualTo(1)
+            // Note: "Quoted text\n\n" would be a better representation of the quoted text. The goal of this test is
+            // not to preserve the current behavior of only ending in one newline, but to make sure we don't add the
+            // last line twice.
+            assertThat(toString()).isEqualTo("Quoted text\n")
+        }
+    }
+
     @Test
     fun chaosQuoting() {
         val message = """