. r F highlight error text in command line reporter

example/main.dart

@@ -7,7 +7,7 @@ void main() {
       Approvals.verifyAll(
         [3, 5, 15],
         options: const Options(
-          comparator: IDEComparator(),
+          reporter: DiffReporter(),
           deleteReceivedFile: true,
         ),
         processor: (items) => fizzBuzz(items).toString(),

example/verify_methods/verify/verify_test.dart

@@ -3,7 +3,8 @@ import 'package:test/test.dart';
 
 void main() {
   test('verify method', () {
-    const String response = '{"result": "success", "data": {"id": 1, "name": "Item"}}';
+    const String response =
+        '{"result": "success", "data": {"id": 1, "name": "Item"}}';
 
     Approvals.verify(
       response,

example/verify_methods/verify_as_json/verify_as_json_test.dart

@@ -23,8 +23,10 @@ void main() {
     Approvals.verifyAsJson(
       jsonItem,
       options: const Options(
-        deleteReceivedFile: true, // Automatically delete the received file after the test.
-        approveResult: true, // Approve the result automatically. You can remove this property after the approved file is created.
+        deleteReceivedFile:
+            true, // Automatically delete the received file after the test.
+        approveResult:
+            true, // Approve the result automatically. You can remove this property after the approved file is created.
       ),
     );
   });

lib/approval_tests.dart

@@ -12,6 +12,7 @@ part 'src/writers/approval_text_writer.dart';
 
 part 'src/core/logger/logger.dart';
 part 'src/core/utils/utils.dart';
+part 'src/core/reporter.dart';
 part 'src/core/options.dart';
 part 'src/core/approval_writer.dart';
 part 'src/core/enums/comporator_ide.dart';
@@ -27,12 +28,15 @@ part 'src/namer/namer.dart';
 part 'src/core/approval_number.dart';
 part 'src/namer/file_namer_options.dart';
 
-part 'src/reporters/comparator.dart';
-part 'src/reporters/command_line_comparator.dart';
-part 'src/reporters/ide_comparator.dart';
-part 'src/reporters/diff_info.dart';
-part 'src/reporters/diff_tools.dart';
+part 'src/core/comparator.dart';
+part 'src/comparator/file_comparator.dart';
+part 'src/reporters/diff_tool/diff_info.dart';
+part 'src/reporters/diff_tool/diff_tools.dart';
 
 part 'src/exceptions/doesnt_match_exception.dart';
 part 'src/exceptions/command_line_comparator_exception.dart';
 part 'src/exceptions/ide_comparator_exception.dart';
+
+part 'src/reporters/command_line/command_line_reporter.dart';
+part 'src/reporters/diff_tool/diff_tool_reporter.dart';
+part 'src/reporters/command_line/colorize.dart';

lib/src/approvals.dart

@@ -34,20 +34,19 @@ class Approvals {
       }
 
       // Check if received file matches the approved file
-      final bool isFilesMatch =
-          ApprovalUtils.filesMatch(namer.approved, namer.received);
+      final bool isFilesMatch = options.comparator.compare(
+        approvedPath: namer.approved,
+        receivedPath: namer.received,
+        isLogError: options.logErrors,
+      );
 
       // Log results and throw exception if files do not match
       if (!isFilesMatch) {
-        options.comparator.compare(
-          approvedPath: namer.approved,
-          receivedPath: namer.received,
-          isLogError: options.logErrors,
-        );
+        options.reporter.report(namer.approved, namer.received);
         throw DoesntMatchException(
           'Test failed: ${namer.approved} does not match ${namer.received}.\n - Approved file path: ${namer.approved}\n - Received file path: ${namer.received}',
         );
-      } else if (isFilesMatch) {
+      } else {
         if (options.logResults) {
           ApprovalLogger.success(
             'Test passed: [${namer.approvedFileName}] matches [${namer.receivedFileName}]\n- Approved file path: ${namer.approved}\n- Received file path: ${namer.received}',

lib/src/comparator/file_comparator.dart

@@ -0,0 +1,31 @@
+part of '../../approval_tests.dart';
+
+/// A class `FileComparator` that implements the `Comparator` interface.
+/// This class is used to compare the content of two files.
+final class FileComparator implements Comparator {
+  const FileComparator();
+
+  @override
+  bool compare({
+    required String approvedPath,
+    required String receivedPath,
+    bool isLogError = true,
+  }) {
+    try {
+      final approved = ApprovalUtils.readFile(path: approvedPath)
+          .replaceAll('\r\n', '\n')
+          .trim();
+      final received = ApprovalUtils.readFile(path: receivedPath)
+          .replaceAll('\r\n', '\n')
+          .trim();
+
+      // Return true if contents of both files match exactly
+      return approved.compareTo(received) == 0;
+    } catch (e) {
+      if (isLogError) {
+        ApprovalLogger.exception(e.toString());
+      }
+      rethrow;
+    }
+  }
+}

lib/src/reporters/comparator.dart → lib/src/core/comparator.dart

@@ -5,7 +5,7 @@ abstract interface class Comparator {
   const Comparator();
 
   /// A method named `compare` for comparing two files.
-  Future<void> compare({
+  bool compare({
     required String approvedPath,
     required String receivedPath,
     bool isLogError = true,

lib/src/core/extensions/approval_string_extensions.dart

@@ -11,6 +11,8 @@ extension StringExtensions on String {
   }) {
     final regExp = RegExp(matchingPattern);
     return replaceAllMapped(
-        regExp, (match) => replacementProvider(match.group(0)!),);
+      regExp,
+      (match) => replacementProvider(match.group(0)!),
+    );
   }
 }

lib/src/core/options.dart

@@ -8,6 +8,9 @@ class Options {
   /// A final variable `comparator` of type `Comparator` used to compare the approved and received files.
   final Comparator comparator;
 
+  /// A final variable `reporter` of type `Reporter` used to report the comparison results.
+  final Reporter reporter;
+
   /// A final bool variable `approveResult` used to determine if the result should be approved after the test.
   final bool approveResult;
 
@@ -27,7 +30,8 @@ class Options {
   const Options({
     this.scrubber = const ScrubNothing(),
     this.approveResult = false,
-    this.comparator = const CommandLineComparator(),
+    this.comparator = const FileComparator(),
+    this.reporter = const CommandLineReporter(),
     this.deleteReceivedFile = false,
     this.namer,
     this.logErrors = true,

lib/src/core/reporter.dart

@@ -0,0 +1,6 @@
+part of '../../approval_tests.dart';
+
+/// `Reporter` is an abstract class for reporting the comparison results.
+abstract interface class Reporter {
+  void report(String approvedPath, String receivedPath);
+}

lib/src/core/utils/utils.dart

@@ -54,24 +54,6 @@ final class ApprovalUtils {
 
   static String lines(int count) => List.filled(count, '=').join();
 
-  // Helper private method to check if contents of two files match
-  static bool filesMatch(String approvedPath, String receivedPath) {
-    try {
-      // Read contents of the approved and received files
-      final approved = ApprovalUtils.readFile(path: approvedPath)
-          .replaceAll('\r\n', '\n')
-          .trim();
-      final received = ApprovalUtils.readFile(path: receivedPath)
-          .replaceAll('\r\n', '\n')
-          .trim();
-
-      // Return true if contents of both files match exactly
-      return approved.compareTo(received) == 0;
-    } catch (_) {
-      rethrow;
-    }
-  }
-
   static void deleteFile(String path) {
     try {
       final File file = File(path);

lib/src/reporters/command_line/colorize.dart

@@ -0,0 +1,19 @@
+part of '../../../approval_tests.dart';
+
+enum _LogColorStyles { red, bgRed }
+
+class _Colorize {
+  static const String esc = "\u{1B}[";
+  final String text;
+
+  const _Colorize(this.text);
+
+  _Colorize apply(_LogColorStyles style) {
+    final appliedText =
+        "$esc${style == _LogColorStyles.red ? '38;2;222;121;121' : '41'}m$text${esc}0m";
+    return _Colorize(appliedText);
+  }
+
+  @override
+  String toString() => text;
+}

lib/src/reporters/command_line/command_line_reporter.dart

@@ -0,0 +1,60 @@
+part of '../../../approval_tests.dart';
+
+/// `CommandLineReporter` is a class for reporting the comparison results using the command line.
+class CommandLineReporter implements Reporter {
+  const CommandLineReporter();
+
+  @override
+  void report(String approvedPath, String receivedPath, {String? message}) {
+    try {
+      final String approvedContent = ApprovalUtils.readFile(path: approvedPath);
+      final String receivedContent = ApprovalUtils.readFile(path: receivedPath);
+
+      final StringBuffer buffer = StringBuffer(message ?? "Differences:\n");
+      final List<String> approvedLines = approvedContent.split('\n');
+      final List<String> receivedLines = receivedContent.split('\n');
+
+      final int maxLines = max(approvedLines.length, receivedLines.length);
+      for (int i = 0; i < maxLines; i++) {
+        final String approvedLine =
+            i < approvedLines.length ? approvedLines[i] : "";
+        final String receivedLine =
+            i < receivedLines.length ? receivedLines[i] : "";
+
+        if (approvedLine != receivedLine) {
+          buffer.writeln(
+            '${ApprovalUtils.lines(20)} Difference at line ${i + 1} ${ApprovalUtils.lines(20)}',
+          );
+          buffer.writeln(
+            'Approved file: ${_highlightDifference(approvedLine, receivedLine)}',
+          );
+          buffer.writeln(
+            'Received file: ${_highlightDifference(receivedLine, approvedLine)}',
+          );
+        }
+      }
+
+      if (buffer.isNotEmpty) {
+        final String reportMessage = buffer.toString();
+        ApprovalLogger.exception(reportMessage);
+      }
+    } catch (e) {
+      rethrow;
+    }
+  }
+
+  String _highlightDifference(String line1, String line2) {
+    final int minLength = min(line1.length, line2.length);
+    final StringBuffer highlighted = StringBuffer();
+
+    for (int i = 0; i < minLength; i++) {
+      if (line1[i] != line2[i]) {
+        highlighted.write(_Colorize(line1[i]).apply(_LogColorStyles.bgRed));
+      } else {
+        highlighted.write(_Colorize(line1[i]).apply(_LogColorStyles.red));
+      }
+    }
+
+    return highlighted.toString();
+  }
+}

lib/src/reporters/diff_info.dart → lib/src/reporters/diff_tool/diff_info.dart

@@ -1,4 +1,4 @@
-part of '../../../approval_tests.dart';
+part of '../../../../approval_tests.dart';
 
 /// `DiffInfo` is a class for storing information about a diff tool.
 class DiffInfo {

lib/src/reporters/ide_comparator.dart → lib/src/reporters/diff_tool/diff_tool_reporter.dart

@@ -1,44 +1,27 @@
-part of '../../approval_tests.dart';
+part of '../../../approval_tests.dart';
 
-/// `IDEComparator` is a class for comparing files using an `IDE`.
-///
-/// Available IDEs:
-/// - `Visual Studio Code`
-/// - `Android Studio`
-final class IDEComparator extends Comparator {
+/// `DiffReporter` is a class for reporting the comparison results using a `Diff Tool`.
+class DiffReporter implements Reporter {
   final ComparatorIDE ide;
   final DiffInfo? customDiffInfo;
 
-  const IDEComparator({
+  const DiffReporter({
     this.ide = ComparatorIDE.vsCode,
     this.customDiffInfo,
   });
 
   @override
-  Future<void> compare({
-    required String approvedPath,
-    required String receivedPath,
-    bool isLogError = true,
-  }) async {
+  Future<void> report(String approvedPath, String receivedPath) async {
+    final DiffInfo diffInfo = _diffInfo;
     try {
-      final File approvedFile = File(approvedPath);
-      final File receivedFile = File(receivedPath);
-
-      if (!_fileExists(approvedFile) || !_fileExists(receivedFile)) {
-        _throwFileException(
-          'Files not found for comparison. Please check the paths: \n\n Approved file path: $approvedPath, \n\n Received file path: $receivedPath.',
-        );
-      }
-      final DiffInfo diffInfo = _diffInfo;
-
       await Process.run(
         diffInfo.command,
         [diffInfo.arg, approvedPath, receivedPath],
       );
     } catch (e, st) {
       throw IDEComparatorException(
         message:
-            'Error during comparison via ${ide.name}. Please try restart your IDE.',
+            'Error during comparison via ${ide.name}. Please try check path to IDE. \n Current path: ${diffInfo.command}.',
         exception: e,
         stackTrace: st,
       );
@@ -67,14 +50,4 @@ final class IDEComparator extends Comparator {
       }
     }
   }
-
-  bool _fileExists(File file) => file.existsSync();
-
-  void _throwFileException(String message) {
-    throw IDEComparatorException(
-      message: message,
-      exception: null,
-      stackTrace: StackTrace.current,
-    );
-  }
 }