[jlox] Test Scanner

jlox/lox/src/test/java/xyz/ctsk/lox/ScannerTest.java

@@ -0,0 +1,56 @@
+package xyz.ctsk.lox;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static xyz.ctsk.lox.TokenType.*;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ScannerTest {
+    @Test
+    void scanTokens_allTypes() {
+        var TEST_STRING = """
+              var return print ; nil
+              * == or - { 10203
+              ( class = false / < if true
+              ) "test string" != for
+              . and } this <= ident + fun , while
+              >= else ! super >
+              """;
+
+        var expected = List.of(
+                VAR, RETURN, PRINT, SEMICOLON, NIL,
+                STAR, EQUAL_EQUAL, OR, MINUS, LEFT_BRACE, NUMBER,
+                LEFT_PAREN, CLASS, EQUAL, FALSE, SLASH, LESS, IF, TRUE,
+                RIGHT_PAREN, STRING, BANG_EQUAL, FOR,
+                DOT, AND, RIGHT_BRACE, THIS, LESS_EQUAL, IDENTIFIER, PLUS, FUN, COMMA, WHILE,
+                GREATER_EQUAL, ELSE, BANG, SUPER, GREATER, EOF
+        );
+
+        var scanner = new Scanner(TEST_STRING);
+        var tokens = scanner.scanTokens();
+        var types = tokens.stream().map(Token::type).toList();
+
+        assertEquals(types, expected);
+    }
+
+    @Test
+    void scanTokens_number() {
+        var numberToken = new Scanner("192304").scanTokens().get(0);
+        assertEquals(numberToken.type(), NUMBER);
+        assertEquals((double) numberToken.literal(), 192304.0);
+    }
+
+    @Test
+    void scanTokens_string() {
+        var testString = """
+                "this is a string"
+                """;
+        var stringToken = new Scanner(testString).scanTokens().get(0);
+
+        assertEquals(stringToken.type(), STRING);
+        assertEquals((String) stringToken.literal(), "this is a string");
+    }
+}