🚧 initiating development of a brand new YAML parser

src/net/sourceforge/plantuml/yaml/parser/YamlLine.java

@@ -0,0 +1,143 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2024, Arnaud Roques
+ *
+ * Project Info:  https://plantuml.com
+ * 
+ * If you like this project or if you find it useful, you can support us at:
+ * 
+ * https://plantuml.com/patreon (only 1$ per month!)
+ * https://plantuml.com/paypal
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.yaml.parser;
+
+import java.util.Optional;
+
+import net.sourceforge.plantuml.annotation.DuplicateCode;
+
+public class YamlLine {
+
+	private final int indent;
+	private final String key;
+	private final String value;
+	private final boolean listItem;
+
+	public static Optional<YamlLine> build(String line) {
+		int count = 0;
+		while (count < line.length() && line.charAt(count) == ' ')
+			count++;
+
+		String trimmedLine = removeYamlComment(line.substring(count).trim());
+
+		if (trimmedLine.isEmpty())
+			return Optional.empty();
+
+		final boolean listItem = trimmedLine.startsWith("- ");
+
+		if (listItem) {
+			count += 2;
+			trimmedLine = trimmedLine.substring(2);
+		}
+
+		final int colonIndex = trimmedLine.indexOf(':');
+		if (colonIndex == -1)
+			return Optional.empty();
+
+		final String rawKey = trimmedLine.substring(0, colonIndex).trim();
+		final String rawValue = trimmedLine.substring(colonIndex + 1).trim();
+
+		return Optional.of(new YamlLine(count, unquote(rawKey), unquote(rawValue), listItem));
+
+	}
+
+	private YamlLine(int indent, String key, String value, boolean listItem) {
+		this.indent = indent;
+		this.key = key;
+		this.value = value;
+		this.listItem = listItem;
+	}
+
+	private static String unquote(String str) {
+		if (str == null || str.length() < 2)
+			return str;
+
+		final char first = str.charAt(0);
+		final char last = str.charAt(str.length() - 1);
+		if ((first == '"' && last == '"') || (first == '\'' && last == '\''))
+			return str.substring(1, str.length() - 1);
+
+		return str;
+	}
+
+	public int getIndent() {
+		return indent;
+	}
+
+	@DuplicateCode(reference = "YamlLines")
+	private static String removeYamlComment(String s) {
+		if (s == null || s.isEmpty())
+			return s;
+
+		char inQuoteChar = '\0';
+
+		if (s.charAt(0) == '#')
+			return "";
+
+		for (int i = 0; i < s.length(); i++) {
+			final char c = s.charAt(i);
+
+			if (c == '\'' || c == '"')
+				if (inQuoteChar == '\0')
+					inQuoteChar = c;
+				else if (c == inQuoteChar)
+					inQuoteChar = '\0';
+
+			if (inQuoteChar == '\0' && i < s.length() - 1 && c == ' ' && s.charAt(i + 1) == '#')
+				return s.substring(0, i);
+
+		}
+
+		return s;
+	}
+
+	public String getKey() {
+		return key;
+	}
+
+	public String getValue() {
+		return value;
+	}
+
+	public boolean isListItem() {
+		return listItem;
+	}
+
+	@Override
+	public String toString() {
+		return "YamlLine(indent=" + indent + ", key=" + key + ", value=" + value + ")";
+	}
+
+}

src/net/sourceforge/plantuml/yaml/parser/YamlParser.java

@@ -0,0 +1,51 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2024, Arnaud Roques
+ *
+ * Project Info:  https://plantuml.com
+ * 
+ * If you like this project or if you find it useful, you can support us at:
+ * 
+ * https://plantuml.com/patreon (only 1$ per month!)
+ * https://plantuml.com/paypal
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.yaml.parser;
+
+import java.util.List;
+
+public class YamlParser {
+
+	public YamlParser(int indentSize) {
+	}
+
+	// In some future, we will return something
+	public void parse(List<String> lines) {
+		System.err.println(lines);
+
+	}
+
+
+}

src/net/sourceforge/plantuml/yaml/parser/YamlSyntaxException.java

@@ -0,0 +1,42 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * (C) Copyright 2009-2024, Arnaud Roques
+ *
+ * Project Info:  https://plantuml.com
+ * 
+ * If you like this project or if you find it useful, you can support us at:
+ * 
+ * https://plantuml.com/patreon (only 1$ per month!)
+ * https://plantuml.com/paypal
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ *
+ *
+ * Original Author:  Arnaud Roques
+ *
+ */
+package net.sourceforge.plantuml.yaml.parser;
+
+public class YamlSyntaxException extends RuntimeException {
+
+	public YamlSyntaxException(String message) {
+		super(message);
+	}
+}

test/net/sourceforge/plantuml/yaml/parser/YamlLineTest.java

@@ -0,0 +1,111 @@
+package net.sourceforge.plantuml.yaml.parser;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+class YamlLineTest {
+
+	@Test
+	void testSimple() {
+		YamlLine yamlLine = YamlLine.build("  name: vibrant").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testQuotedKey() {
+		YamlLine yamlLine = YamlLine.build("  \"name\": vibrant").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testQuotedValue() {
+		YamlLine yamlLine = YamlLine.build("  name: \"vibrant\"").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testQuotedKeyAndValue() {
+		YamlLine yamlLine = YamlLine.build("  \"name\": \"vibrant\"").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testKeyWithSpaces() {
+		YamlLine yamlLine = YamlLine.build("  \"full name\": \"John Doe\"").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("full name", yamlLine.getKey());
+		assertEquals("John Doe", yamlLine.getValue());
+	}
+
+	@Test
+	void testValueWithComment() {
+		YamlLine yamlLine = YamlLine.build("  name: vibrant # primary color").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("vibrant", yamlLine.getValue());
+		assertEquals("name", yamlLine.getKey());
+	}
+
+	@Test
+	void testCommentLineOnly() {
+		assertFalse(YamlLine.build("  # This is a comment").isPresent());
+	}
+
+	@Test
+	void testNoIndent() {
+		YamlLine yamlLine = YamlLine.build("name: vibrant").get();
+		assertEquals(0, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testExtraSpacesAroundColon() {
+		YamlLine yamlLine = YamlLine.build("  name  :    vibrant  ").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("vibrant", yamlLine.getValue());
+	}
+
+	@Test
+	void testMissingValue() {
+		YamlLine yamlLine = YamlLine.build("  name:").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("name", yamlLine.getKey());
+		assertEquals("", yamlLine.getValue());
+	}
+
+	@Test
+	void testSharpInString() {
+		YamlLine yamlLine = YamlLine.build("  \"full name\": \"John # Doe\"").get();
+		assertEquals(2, yamlLine.getIndent());
+		assertEquals("full name", yamlLine.getKey());
+		assertEquals("John # Doe", yamlLine.getValue());
+	}
+
+	@Test
+	void testMissingColon() {
+		assertFalse(YamlLine.build("  name vibrant").isPresent());
+	}
+
+
+	@Test
+	void testIsListItem() {
+		YamlLine yamlLine = YamlLine.build("    - primary: ffcc00").get();
+		assertEquals(6, yamlLine.getIndent());
+		assertTrue(yamlLine.isListItem());
+		assertEquals("primary", yamlLine.getKey());
+		assertEquals("ffcc00", yamlLine.getValue());
+	}
+
+}

test/net/sourceforge/plantuml/yaml/parser/YamlParserTest.java

@@ -0,0 +1,23 @@
+package net.sourceforge.plantuml.yaml.parser;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+class YamlParserTest {
+
+    @ParameterizedTest
+    @ValueSource(strings = {
+        "metadata:",
+        "  name: vibrant:",
+        "  type: \"dark\":"
+    })
+    void testSimple(String s) {
+        YamlParser parser = new YamlParser(2);
+        List<String> list = Arrays.asList(s);
+        parser.parse(list);
+    }
+}