Replace some nullable types with late types

Author: AlessioLuciani

example/test/pdf_text_test.dart

@@ -1,5 +1,5 @@
 @Skip(
-    'To run these tests, make sure an emulator or a real device is connected, then \'cd example\' and : \'flutter run test/pfd_text_test.dart\'')
+    'To run these tests, make sure an emulator or a real device is connected, then \'cd example\' and : \'flutter run test/pdf_text_test.dart\'')
 import 'dart:io';
 
 import 'package:flutter/foundation.dart';
@@ -21,13 +21,13 @@ void main() async {
 
   final testDirectoryPath =
       join((await getTemporaryDirectory()).path, "temp_pdf_text_dir");
-  final PdfTestUtils  pdfUtils = PdfTestUtils(testDirectoryPath);
-  final File  encryptedPdf = File(join(testDirectoryPath, "encrypted.pdf"));
+  final PdfTestUtils pdfUtils = PdfTestUtils(testDirectoryPath);
+  final File encryptedPdf = File(join(testDirectoryPath, "encrypted.pdf"));
 
   setUpAll(() async {
     /// init mock http client so that the PDFDoc.fromUrl() obtains the mocked version
     ClientProvider(
-        client: MockClient((Request  req) => Future.value(Response.bytes(
+        client: MockClient((Request req) => Future.value(Response.bytes(
             File(join(testDirectoryPath, req.url.path.split("/").last))
                 .readAsBytesSync(),
             200))));
@@ -56,7 +56,7 @@ void main() async {
           subject: "The most profound theological book ever written",
           keywords: "Doctor,Angelicus");
 
-      List<String >  page = [
+      List<String> page = [
         "Et ut intentio nostra sub aliquibus certis limitibus comprehendatur,",
         "necessarium est primo investigare de ipsa sacra doctrina, qualis sit, et ad quæ se extendat.",
         "Circa quæ quærenda sunt decem.",
@@ -65,11 +65,11 @@ void main() async {
         "Tertio, utrum sit una vel plures."
       ];
 
-      File  pdf = await pdfUtils.createPdfFile([page], info: info);
+      File pdf = await pdfUtils.createPdfFile([page], info: info);
 
-      PDFDoc  fromFile = await PDFDoc.fromFile(pdf);
-      PDFDoc  fromPath = await PDFDoc.fromPath(pdf.path);
-      PDFDoc  fromUrl =
+      PDFDoc fromFile = await PDFDoc.fromFile(pdf);
+      PDFDoc fromPath = await PDFDoc.fromPath(pdf.path);
+      PDFDoc fromUrl =
           await PDFDoc.fromURL("http://localhost/${basename(pdf.path)}");
 
       await forEach([fromFile, fromPath, fromUrl], (dynamic doc) async {
@@ -91,24 +91,24 @@ void main() async {
           subject: "Detecitve stories",
           keywords: "Holmes,Watson");
 
-      List<String >  page1 = [
+      List<String> page1 = [
         "To Sherlock Holmes she is always the woman.",
         "I have seldom heard him mention her under any other name.",
         "In his eyes she eclipses and predominates the whole of her sex.",
       ];
 
-      List<String >  page2 = [
+      List<String> page2 = [
         "himself in a false position. He never spoke of the softer",
         "They were admirable things for the observer-excellent for",
         "But for the trained reasoner to admit such intrusions into",
         "was to introduce a distracting factor which might throw a",
       ];
 
-      File  pdf = await pdfUtils.createPdfFile([page1, page2], info: info);
+      File pdf = await pdfUtils.createPdfFile([page1, page2], info: info);
 
-      PDFDoc  fromFile = await PDFDoc.fromFile(pdf);
-      PDFDoc  fromPath = await PDFDoc.fromPath(pdf.path);
-      PDFDoc  fromUrl =
+      PDFDoc fromFile = await PDFDoc.fromFile(pdf);
+      PDFDoc fromPath = await PDFDoc.fromPath(pdf.path);
+      PDFDoc fromUrl =
           await PDFDoc.fromURL("http://localhost/${basename(pdf.path)}");
 
       await forEach([fromFile, fromPath, fromUrl], (dynamic doc) async {
@@ -126,11 +126,11 @@ void main() async {
     test("should read text from a password protected pdf file", () async {
       expect(encryptedPdf.existsSync(), true);
 
-      PDFDoc  fromFile =
+      PDFDoc fromFile =
           await PDFDoc.fromFile(encryptedPdf, password: "password");
-      PDFDoc  fromPath =
+      PDFDoc fromPath =
           await PDFDoc.fromPath(encryptedPdf.path, password: "password");
-      PDFDoc  fromUrl = await PDFDoc.fromURL(
+      PDFDoc fromUrl = await PDFDoc.fromURL(
           "http://localhost/${basename(encryptedPdf.path)}",
           password: "password");
 
@@ -145,7 +145,7 @@ void main() async {
     test("should fail if the password is invalid", () async {
       expect(encryptedPdf.existsSync(), true);
 
-      int  exceptionCount = 0;
+      int exceptionCount = 0;
 
       final fromFile =
           () => PDFDoc.fromFile(encryptedPdf, password: "invalid-password");
@@ -158,7 +158,7 @@ void main() async {
       await forEach([fromFile, fromPath, fromURL], (dynamic foo) async {
         try {
           await foo();
-        } on PlatformException  catch (e) {
+        } on PlatformException catch (e) {
           expect(
               e.message,
               contains(isIos
@@ -174,4 +174,4 @@ void main() async {
           reason: "All attempts with invalid password must fail!");
     });
   });
-}
+}

lib/pdf_text.dart

@@ -14,9 +14,9 @@ const String _TEMP_DIR_NAME = ".flutter_pdf_text";
 ///  to be used: [PDFDoc.fromFile], [PDFDoc.fromPath], [PDFDoc.fromURL].
 class PDFDoc {
   late File _file;
-  PDFDocInfo? _info;
-  List<PDFPage>? _pages;
-  String? _password;
+  late PDFDocInfo _info;
+  late List<PDFPage> _pages;
+  late String _password;
 
   PDFDoc._internal();
 
@@ -26,18 +26,14 @@ class PDFDoc {
     var doc = PDFDoc._internal();
     doc._password = password;
     doc._file = file;
-    Map? data;
+    late Map data;
     try {
       data = await _CHANNEL
           .invokeMethod('initDoc', {"path": file.path, "password": password});
     } on Exception catch (e) {
       return Future.error(e);
     }
-    doc._pages =
-        List.generate(data!["length"], (index) => PDFPage._fromDoc(doc, index));
-    // for (int  i = 0; i < data!["length"]; i++) {
-    //   doc._pages!.add(PDFPage._fromDoc(doc, i));
-    // }
+    doc._pages = List.generate(data["length"], (i) => PDFPage._fromDoc(doc, i));
     doc._info = PDFDocInfo._fromMap(data["info"]);
     return doc;
   }
@@ -71,27 +67,27 @@ class PDFDoc {
   }
 
   /// Gets the page of the document at the given page number.
-  PDFPage pageAt(int pageNumber) => _pages![pageNumber - 1];
+  PDFPage pageAt(int pageNumber) => _pages[pageNumber - 1];
 
   /// Gets the pages of this document.
   /// The pages indexes start at 0, but the first page has number 1.
   /// Therefore, if you need to access the 5th page, you will do:
   /// var page = doc.pages[4]
   /// print(page.number) -> 5
-  List<PDFPage>? get pages => _pages;
+  List<PDFPage> get pages => _pages;
 
   /// Gets the number of pages of this document.
-  int get length => _pages!.length;
+  int get length => _pages.length;
 
   /// Gets the information of this document.
-  PDFDocInfo? get info => _info;
+  PDFDocInfo get info => _info;
 
   /// Gets the entire text content of the document.
   Future<String> get text async {
     // Collecting missing pages
 
     List<int> missingPagesNumbers = [];
-    _pages!.forEach((page) {
+    _pages.forEach((page) {
       if (page._text == null) {
         missingPagesNumbers.add(page.number);
       }
@@ -117,12 +113,8 @@ class PDFDoc {
       pageAt(missingPagesNumbers[i])._text = missingPagesTexts[i];
     }
 
-    /// Removed the \n added at the end of each page here (potentially a breaking change!).
-    /// Since every page can be retrieved individually, the client knows exactly
-    /// where it begins and where it ends, therefore there is no benefit of
-    /// introducing an artificial page separator that is not part of the pdf
-    /// document per se
-    return _pages!.fold<String>("", (pv, page) => "$pv${page._text}");
+    /// Returning the entire text, concatenating all pages
+    return _pages.fold<String>("", (pv, page) => "$pv${page._text}");
   }
 
   /// Deletes the file related to this [PDFDoc].
@@ -165,7 +157,7 @@ class PDFPage {
   /// Gets the text of this page.
   /// The text retrieval is lazy. So the text of a page is only loaded when
   /// it is requested for the first time.
-  Future<String?> get text async {
+  Future<String> get text async {
     // Loading the text
     if (_text == null) {
       try {
@@ -178,7 +170,7 @@ class PDFPage {
         return Future.error(e);
       }
     }
-    return _text;
+    return _text!;
   }
 
   /// Gets the page number.