feat: added lambda processing instead of returning a list

README.md

@@ -72,6 +72,14 @@ val someApi = TODO("Not a real API object")
 // Returns a playlist in the M3U format
 val m3uContent: String = someApi.getPlaylist("Best of Willy Astor")
 val entries: List<M3uEntry> = M3uParser.parse(m3uContent)
+
+
+// You can also use a lambda for processing each entry instead of returning a List
+val m3uFile = Paths.get("myplaylist.m3u")
+M3uParser.parse(m3uFile) { entry ->
+    println(entry->name)
+}
+
 ```
 
 ### Nested playlists

buildConfig/detekt.yml

@@ -3,3 +3,8 @@ comments:
     active: true
   UndocumentedPublicFunction:
     active: true
+complexity:
+  TooManyFunctions:
+    ignoreOverridden: true
+    thresholdInClasses: 15
+    thresholdInObjects: 15

src/main/kotlin/net/bjoernpetersen/m3u/M3uParser.kt

@@ -55,7 +55,28 @@
     @JvmOverloads
     fun parse(m3uFile: Path, charset: Charset = Charsets.UTF_8): List<M3uEntry> {
         require(Files.isRegularFile(m3uFile)) { "$m3uFile is not a file" }
-        return parse(Files.lines(m3uFile, charset).asSequence(), m3uFile.parent)
+        val entries = mutableListOf<M3uEntry>()
+        parse(Files.lines(m3uFile, charset).asSequence(), m3uFile.parent) { entry -> entries.add(entry) }
+        return entries
+    }
+
+    /**
+     * Parses the specified file.
+     *
+     * Comment lines and lines which can't be parsed are dropped.
+     *
+     * @param m3uFile a path to an .m3u file
+     * @param charset the file's encoding, defaults to UTF-8
+     * @param processFun a Unit to process each m3uentry
+     * @throws IOException if file can't be read
+     * @throws IllegalArgumentException if file is not a regular file
+     */
+    @Throws(IOException::class)
+    @JvmStatic
+    @JvmOverloads
+    fun parse(m3uFile: Path, charset: Charset = Charsets.UTF_8, processFun: (M3uEntry) -> Unit) {
+        require(Files.isRegularFile(m3uFile)) { "$m3uFile is not a file" }
+        parse(Files.lines(m3uFile, charset).asSequence(), m3uFile.parent, processFun)
     }
 
     /**
@@ -70,7 +91,30 @@
     @JvmStatic
     @JvmOverloads
     fun parse(m3uContentReader: InputStreamReader, baseDir: Path? = null): List<M3uEntry> {
-        return m3uContentReader.buffered().useLines { parse(it, baseDir) }
+        val entries = mutableListOf<M3uEntry>()
+        m3uContentReader.buffered().useLines {
+            parse(it, baseDir) {
+                    entry ->
+                entries.add(entry)
+            }
+        }
+        return entries
+    }
+
+    /**
+     * Parses the [InputStream] from the specified reader.
+     *
+     * Comment lines and lines which can't be parsed are dropped.
+     *
+     * @param m3uContentReader a reader reading the content of an `.m3u` file
+     * @param baseDir a base dir for resolving relative paths
+     * @param processFun a Unit to process each m3uentry
+     *
+     */
+    @JvmStatic
+    @JvmOverloads
+    fun parse(m3uContentReader: InputStreamReader, baseDir: Path? = null, processFun: (M3uEntry) -> Unit) {
+        return m3uContentReader.buffered().useLines { parse(it, baseDir, processFun) }
     }
 
     /**
@@ -85,7 +129,28 @@
     @JvmStatic
     @JvmOverloads
     fun parse(m3uContent: String, baseDir: Path? = null): List<M3uEntry> {
-        return parse(m3uContent.lineSequence(), baseDir)
+        val entries = mutableListOf<M3uEntry>()
+        parse(m3uContent, baseDir) {
+                entry ->
+            entries.add(entry)
+        }
+        return entries
+    }
+
+    /**
+     * Parses the specified content of a `.m3u` file.
+     *
+     * Comment lines and lines which can't be parsed are dropped.
+     *
+     * @param m3uContent the content of a `.m3u` file
+     * @param baseDir a base dir for resolving relative paths
+     * @param processFun a Unit to process each m3uentry
+     *
+     */
+    @JvmStatic
+    @JvmOverloads
+    fun parse(m3uContent: String, baseDir: Path? = null, processFun: (M3uEntry) -> Unit) {
+        parse(m3uContent.lineSequence(), baseDir, processFun)
     }
 
     /**
@@ -106,14 +171,14 @@
     }
 
     @Suppress("NestedBlockDepth", "ReturnCount")
-    private fun parse(lines: Sequence<String>, baseDir: Path?): List<M3uEntry> {
+    private fun parse(lines: Sequence<String>, baseDir: Path?, processFun: (M3uEntry) -> Unit) {
         val filtered = lines
             .filterNot { it.isBlank() }
             .map { it.trimEnd() }
             .dropWhile { it == EXTENDED_HEADER }
             .iterator()
 
-        if (!filtered.hasNext()) return emptyList()
+        if (!filtered.hasNext()) return
 
         val entries = LinkedList<M3uEntry>()
 
@@ -134,7 +199,7 @@
                 if (filtered.hasNext()) {
                     currentLine = filtered.next()
                 } else {
-                    return entries
+                    return
                 }
             }
 
@@ -149,13 +214,13 @@
             match = null
 
             if (entry != null) {
-                entries.add(entry)
+                processFun(entry)
             } else {
                 logger.warn { "Ignored line $currentLine" }
             }
         }
 
-        return entries
+        return
     }
 
     private fun parseSimple(location: String, baseDir: Path?): M3uEntry? {

src/test/kotlin/net/bjoernpetersen/m3u/M3uParserExampleTest.kt

@@ -124,6 +124,36 @@ class M3uParserExampleTest {
         assertEquals("https://i.imgur.com/CnIVW9o.jpg", withLogo.metadata.logo)
     }
 
+    @TestFactory
+    fun testWikiLambda(): List<DynamicTest> {
+        return listOf(
+            "wiki_mixed.m3u",
+            "wiki_mixed_empty_lines.m3u",
+        ).map { name ->
+            dynamicTest(name) {
+                val entries = mutableListOf<M3uEntry>()
+                M3uParser.parse(javaClass.getResourceAsStream(name).reader()) { entry ->
+                    entries.add(entry)
+                }
+                assertEquals(7, entries.size)
+
+                val simple = listOf(entries[1], entries[4])
+                simple.forEach {
+                    assertThat(it)
+                        .returns(null, M3uEntry::duration)
+                        .returns(null, M3uEntry::title)
+                }
+
+                val extended = entries.filterNot { it in simple }
+                extended.forEach { entry ->
+                    assertThat(entry)
+                        .matches { it.duration != null }
+                        .matches { it.title != null }
+                }
+            }
+        }
+    }
+
     @Test
     fun testRecursiveResolution() {
         val files = listOf("rec_1.m3u", "rec_2.m3u", "rec_3.m3u")