Adding a test to validate line numbers and fix for multiline strings

### What's done:
- On multiline strings we forgot to update isMultiline flag while decoding and parsing
- Adding extra info to prettyPrint
- Adding a test for validation of line numbers
- Removing deprecated 'content' from the TomlNode

ktoml-core/src/commonMain/kotlin/com/akuleshov7/ktoml/decoders/TomlMainDecoder.kt

@@ -101,10 +101,10 @@ public class TomlMainDecoder(
             is TomlKeyValuePrimitive -> node
             is TomlKeyValueArray -> node
             // empty nodes will be filtered by iterateUntilWillFindAnyKnownName() method, but in case we came into this
-            // branch, we should throw an exception as it is not expected at all and we should catch this in tests
+            // branch, we should throw an exception as it is not expected at all, and we should catch this in tests
             else ->
                 throw InternalDecodingException(
-                    "Node of type [${node::class}] should not be processed in TomlDecoder.decodeValue(): <${node.content}>."
+                    "Node of type [${node::class}] should not be processed in TomlDecoder.decodeValue(): <${node}>."
                 )
         }
     }

ktoml-core/src/commonMain/kotlin/com/akuleshov7/ktoml/tree/nodes/TomlNode.kt

@@ -29,13 +29,6 @@ public sealed class TomlNode(
     comments: List<String>,
     public val inlineComment: String
 ) {
-    @Deprecated(
-        message = "content was replaced with toString; will be removed in future releases.",
-        replaceWith = ReplaceWith("toString()")
-    )
-    @Suppress("CUSTOM_GETTERS_SETTERS")
-    public val content: String get() = toString()
-
     /**
      * A list of comments prepended to the node.
      */
@@ -187,20 +180,22 @@ public sealed class TomlNode(
 
     /**
      * print the structure of parsed AST tree
+     * Important: as prettyPrint calls toString() of the node, and not just prints the value, but emits and reconstruct a source string,
+     * so in some cases (for example in case of multiline strings) it can work incorrectly.
      */
     @Suppress("DEBUG_PRINT")
-    public fun prettyPrint() {
+    public fun prettyPrint(emitLine: Boolean = false) {
         val sb = StringBuilder()
-        prettyPrint(this, sb)
+        prettyPrint(this, sb, emitLine)
         println(sb.toString())
     }
 
     /**
      * @return the string with AST tree visual representation
      */
-    public fun prettyStr(): String {
+    public fun prettyStr(emitLine: Boolean = false): String {
         val sb = StringBuilder()
-        prettyPrint(this, sb)
+        prettyPrint(this, sb, emitLine)
         return sb.toString()
     }
 
@@ -233,37 +228,6 @@ public sealed class TomlNode(
         }
     }
 
-    @Deprecated(
-        message = "TomlConfig is deprecated; use TomlOutputConfig instead. Will be removed in next releases.",
-        replaceWith = ReplaceWith(
-            "write(emitter, config, multiline)",
-            "com.akuleshov7.ktoml.TomlOutputConfig"
-        )
-    )
-    public fun write(
-        emitter: TomlEmitter,
-        config: TomlConfig,
-        multiline: Boolean = false
-    ): Unit = write(emitter, config.output, multiline)
-
-    /**
-     * Writes this node as text to [emitter].
-     *
-     * @param emitter The [TomlEmitter] instance to write to.
-     * @param config The [TomlConfig] instance. Defaults to the node's config.
-     * @param multiline Whether to write the node over multiple lines, if possible.
-     */
-    @Deprecated(
-        message = "The multiline parameter overload is deprecated, use the multiline" +
-                " property on supported TomlValue types instead. Will be removed in next releases.",
-        replaceWith = ReplaceWith("write(emitter, config)")
-    )
-    public fun write(
-        emitter: TomlEmitter,
-        config: TomlOutputConfig = TomlOutputConfig(),
-        multiline: Boolean = false
-    ): Unit = write(emitter, config)
-
     /**
      * Writes this node as text to [emitter].
      *
@@ -328,6 +292,10 @@ public sealed class TomlNode(
             .writeNode(this)
             .replace(" = ", "=")
 
+    internal fun print(emitLine: Boolean = false): String =
+        "${this::class.simpleName} ($this)${if (emitLine) "[line:${this.lineNo}]" else ""}\n"
+
+
     public companion object {
         // number of spaces that is used to indent levels
         internal const val INDENTING_LEVEL = 4
@@ -342,12 +310,14 @@ public sealed class TomlNode(
         public fun prettyPrint(
             node: TomlNode,
             result: StringBuilder,
+            emitLine: Boolean = false,
             level: Int = 0
         ) {
             val spaces = " ".repeat(INDENTING_LEVEL * level)
-            result.append("$spaces - ${node::class.simpleName} ($node)\n")
+            // we are using print() method here instead of toString()
+            result.append("$spaces - ${node.print(emitLine)}")
             node.children.forEach { child ->
-                prettyPrint(child, result, level + 1)
+                prettyPrint(child, result, emitLine, level + 1, )
             }
         }
     }

ktoml-core/src/commonMain/kotlin/com/akuleshov7/ktoml/tree/nodes/pairs/values/TomlLiteralString.kt

@@ -28,7 +28,7 @@ public class TomlLiteralString internal constructor(
         content: String,
         lineNo: Int,
         config: TomlInputConfig = TomlInputConfig()
-    ) : this(content.verifyAndTrimQuotes(lineNo, config))
+    ) : this(content.verifyAndTrimQuotes(lineNo, config), content.contains("\n"))
 
     @Deprecated(
         message = "TomlConfig is deprecated; use TomlInputConfig instead. Will be removed in next releases."
@@ -45,7 +45,7 @@ public class TomlLiteralString internal constructor(
 
     override fun write(
         emitter: TomlEmitter,
-        config: TomlOutputConfig
+        config: TomlOutputConfig,
     ) {
         val content = content as String
 

ktoml-core/src/commonTest/kotlin/com/akuleshov7/ktoml/parsers/SetLineNoTest.kt

@@ -0,0 +1,58 @@
+package com.akuleshov7.ktoml.parsers
+
+import com.akuleshov7.ktoml.Toml
+import com.akuleshov7.ktoml.tree.nodes.TomlKeyValuePrimitive
+import kotlin.test.Test
+import kotlin.test.assertContentEquals
+import kotlin.test.assertEquals
+
+class SetLineNoTest {
+    @Test
+    fun checkingLineNumbers() {
+        val string = """
+            
+            # comment 1
+            
+            [a] # comment 2
+            # comment 3
+             test = 1 # comment 4
+             
+             # ====
+             
+             [[a.b]] # comment 5 
+                test = 1
+                
+             mls = '''
+                  1
+                  2
+                  3
+             '''
+             
+             mla = [
+                 "a",
+                 "b",
+                 "c"
+                 ]
+        """.trimIndent()
+        val parsedToml = Toml.tomlParser.parseString(string)
+
+        parsedToml.prettyPrint(true)
+        assertEquals(
+            """
+                 | - TomlFile (rootNode)[line:0]
+                 |     - TomlTablePrimitive ([a])[line:4]
+                 |         - TomlKeyValuePrimitive (test=1)[line:6]
+                 |         - TomlArrayOfTables ([[a.b]])[line:10]
+                 |             - TomlArrayOfTablesElement (technical_node)[line:10]
+                 |                 - TomlKeyValuePrimitive (test=1)[line:11]
+                 |                 - TomlKeyValuePrimitive (mls='''      1
+                 |      2
+                 |      3
+                 | ''')[line:13]
+                 |                 - TomlKeyValueArray (mla=[ "a", "b", "c" ])[line:18]
+                 |
+            """.trimMargin(),
+            parsedToml.prettyStr(true)
+        )
+    }
+}