finished writing chapter 2

analysis_options.yaml

@@ -5,10 +5,16 @@ include: package:pedantic/analysis_options.yaml
 
 # For lint rules and documentation, see http://dart-lang.github.io/linter/lints.
 # Uncomment to specify additional rules.
-# linter:
-#   rules:
+linter:
+  rules:
+    info:
+      - prefer_double_quotes
+
 #     - camel_case_types
 
 analyzer:
+  errors:
+    - unused_local_variable: info
+
 #   exclude:
 #     - path/to/excluded/files/**

test/chapter_1_asserts_test.dart → test/chapter_1_about_asserts_test.dart

@@ -15,12 +15,10 @@ void main() {
    *
    * Try to fix the following tests
    */
-  group('Expectations => ', () {
-    test('Try to fix the following tests', () {});
-
+  group('About Asserts', () {
     test('Should expect true', () {
       print('Your journey begins here: ');
-      expect(true, false, reason: "Hint: Replace the word 'false' with 'true'");
+      expect(true, true, reason: "Hint: Replace the word 'false' with 'true'");
     });
 
     test('We will compare often values with each other', () {

test/chapter_2_about_string_test.dart

@@ -0,0 +1,116 @@
+import 'package:test/test.dart';
+
+const your_answer = null;
+
+void main() {
+  group('About Strings', () {
+    test('Double quoted strings are strings', () {
+      var string = "Hello, world";
+      expect(your_answer, isA<String>());
+    });
+
+    test('single quoted strings are strings', () {
+      var string = 'Goodbye, world';
+      expect(your_answer, isA<String>());
+    });
+
+    test('triple quoted strings are also strings', () {
+      var string = """Hallo Welt""";
+      expect(your_answer, isA<String>());
+    });
+
+    test('triple single quoted strings work too', () {
+      var string = '''Bonjour tout le monde!''';
+      expect(your_answer, isA<String>());
+    });
+
+    test('raw strings are also strings', () {
+      var string = r"Konnichi wa, world!";
+      expect(your_answer, isA<String>());
+    });
+
+    test('use single quotes to create string with double quotes', () {
+      var string = 'He said, "Go Away."';
+      assert(your_answer, string);
+    });
+
+    test("use double quotes to create string with single quotes", () {
+      var string = "Don't";
+      expect(your_answer, string);
+    });
+
+    test("use backslash for escaping quotes in strings", () {
+      var a = "He said, \"Don't\"";
+      var b = 'He said, "Don\'t"';
+      assert(your_answer, a == b);
+    });
+
+    test("triple quoted strings can span lines", () {
+      var string = """
+      Greetings,
+      Partner!
+      """;
+
+      expect(your_answer, string.length);
+    });
+
+    test("triple quoted strings need less escaping", () {
+      var a = "Hello \"world\".";
+      var b = """Hello "world".""";
+
+      expect(your_answer, a == b);
+    });
+
+    test("escaping quotes at the end of a triple quoted string", () {
+      var string = """Hello "world\"""";
+      expect(your_answer, string);
+    });
+
+    test("plus concatenates strings", () {
+      var string = "Hello" + ", " + "World";
+      expect(your_answer, string);
+    });
+
+    test("\$ is a better concatination", () {
+      var a = "Hello";
+      var b = "World";
+
+      expect(your_answer, "$a, $b");
+    });
+
+    test("With \${} you are able to access attributes and concatinate them",
+        () {
+      var string = "Concatination is great!";
+      expect(your_answer, "${string.length}");
+    });
+
+    test("adjacent strings are concatenated automatically", () {
+      var string = "Hello" ", " "World";
+      expect(your_answer, string);
+    });
+
+    test("plus will not modify the original strings", () {
+      var foo = "Hello, ";
+      var bar = "World";
+      var string = foo + bar;
+
+      expect(your_answer, foo);
+      expect(your_answer, bar);
+    });
+
+    test("plus equals will append to the end of the string", () {
+      var foo = "Hello, ";
+      var bar = "World";
+      foo += bar;
+      expect(your_answer, foo);
+    });
+
+    test("plus equals also leaves original string unmodified", () {
+      var original = "Hello, ";
+      var foo = original;
+      var bar = "World";
+      foo += bar;
+      expect(your_answer, original);
+    });
+  });
+}