feat(dart): add Dart language support with Dart 3 class modifiers

build.gradle.kts

@@ -185,6 +185,7 @@ dependencies {
     jacocoAggregation(project(":chapi-ast-cpp"))
     jacocoAggregation(project(":chapi-ast-protobuf"))
     jacocoAggregation(project(":chapi-ast-swift"))
+    jacocoAggregation(project(":chapi-ast-dart"))
 
     jacocoAggregation(project(":chapi-parser-toml"))
     jacocoAggregation(project(":chapi-parser-cmake"))

chapi-ast-dart/build.gradle.kts

@@ -0,0 +1,61 @@
+plugins {
+    id("antlr")
+    java
+    kotlin("jvm")
+    kotlin("plugin.serialization") version "1.9.24"
+
+    `jacoco-conventions`
+}
+
+repositories {
+    mavenCentral()
+    mavenLocal()
+}
+
+dependencies {
+    antlr("org.antlr:antlr4:4.13.2")
+
+    // project deps
+    implementation(project(":chapi-domain"))
+
+    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3")
+
+    implementation(kotlin("stdlib-jdk8"))
+    implementation(kotlin("reflect"))
+    // Kotlin reflection.
+    testImplementation(kotlin("test"))
+
+    // JUnit 5
+    testImplementation("org.junit.jupiter:junit-jupiter-api:5.10.2")
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.10.2")
+    testRuntimeOnly("org.junit.platform:junit-platform-console:1.10.2")
+
+    implementation("org.antlr:antlr4:4.13.2")
+    implementation("org.antlr:antlr4-runtime:4.13.2")
+}
+
+sourceSets.main {
+    // Append generated-src to existing source directories (don't replace src/main/java)
+    java.srcDir("${project.layout.buildDirectory.get().asFile}/generated-src")
+}
+
+tasks.generateGrammarSource {
+    maxHeapSize = "128m"
+    arguments = arguments + listOf("-package", "chapi.ast.antlr") + listOf("-visitor", "-long-messages")
+    outputDirectory = file("${project.layout.buildDirectory.get().asFile}/generated-src/chapi/ast/antlr")
+}
+
+tasks.withType<AntlrTask> {
+
+}
+
+tasks.named("compileKotlin") {
+    dependsOn(tasks.withType<AntlrTask>())
+}
+
+tasks.withType<Test> {
+    useJUnitPlatform()
+    testLogging {
+        events("passed", "skipped", "failed")
+    }
+}

chapi-ast-dart/src/main/antlr/Dart2Lexer.g4

@@ -0,0 +1,245 @@
+/* Generated Mon, Jun 13, 2022 8:11:58 AM EST
+ *
+ * Copyright (c) 2022, 2023 Ken Domino
+ * Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
+ * for details. All rights reserved. Use of this source code is governed by a
+ * BSD-style license that can be found in the LICENSE file.
+ *
+ * This grammar is generated from the CFG contained in:
+ * https://github.com/dart-lang/language/blob/70eb85cf9a6606a9da0de824a5d55fd06de1287f/specification/dartLangSpec.tex
+ *
+ * The bash script used to scrape and the refactor the grammar is here:
+ * https://github.com/kaby76/ScrapeDartSpec/blob/master/refactor.sh
+ *
+ * Note: the CFG in the Specification is in development, and is for approximately
+ * Dart version 2.15. The Specification is not up-to-date vis-a-vis the actual
+ * compiler code, located here:
+ * https://github.com/dart-lang/sdk/tree/main/pkg/_fe_analyzer_shared/lib/src/parser
+ * Some of the refactorings that are applied are to bring the code into a working
+ * Antlr4 parser. Other refactorings replace some of the rules in the Spec because
+ * the Spec is incorrect, or incomplete.
+ *
+ * This grammar has been checked against a large subset (~370 Dart files) of the Dart SDK:
+ * https://github.com/dart-lang/sdk/tree/main/sdk/lib
+ * A copy of the SDK is provided in the examples for regression testing.
+ */
+
+// $antlr-format alignTrailingComments true, columnLimit 150, maxEmptyLinesToKeep 1, reflowComments false, useTab false
+// $antlr-format allowShortRulesOnASingleLine true, allowShortBlocksOnASingleLine true, minEmptyLines 0, alignSemicolons ownLine
+// $antlr-format alignColons trailing, singleLineOverrulesHangingColon true, alignLexerCommands true, alignLabels true, alignTrailers true
+
+lexer grammar Dart2Lexer;
+
+options {
+    superClass = Dart2LexerBase;
+}
+
+// Insert here @header for C++ lexer.
+
+A           : '&';
+AA          : '&&';
+AE          : '&=';
+AT          : '@';
+C           : ',';
+CB          : ']';
+CBC         : '}';
+CIR         : '^';
+CIRE        : '^=';
+CO          : ':';
+CP          : ')';
+D           : '.';
+DD          : '..';
+DDD         : '...';
+DDDQ        : '...?';
+EE          : '==';
+EG          : '=>';
+EQ          : '=';
+GT          : '>';
+LT          : '<';
+LTE         : '<=';
+LTLT        : '<<';
+LTLTE       : '<<=';
+ME          : '-=';
+MINUS       : '-';
+MM          : '--';
+NE          : '!=';
+NOT         : '!';
+OB          : '[';
+OBC         : '{';
+OP          : '(';
+P           : '|';
+PC          : '%';
+PE          : '%=';
+PL          : '+';
+PLE         : '+=';
+PLPL        : '++';
+PO          : '#';
+POE         : '|=';
+PP          : '||';
+QU          : '?';
+QUD         : '?.';
+QUDD        : '?..';
+QUQU        : '??';
+QUQUEQ      : '??=';
+SC          : ';';
+SE          : '/=';
+SL          : '/';
+SQS         : '~/';
+SQSE        : '~/=';
+SQUIG       : '~';
+ST          : '*';
+STE         : '*=';
+ABSTRACT_   : 'abstract';
+AS_         : 'as';
+ASSERT_     : 'assert';
+ASYNC_      : 'async';
+AWAIT_      : 'await';
+BREAK_      : 'break';
+CASE_       : 'case';
+CATCH_      : 'catch';
+CLASS_      : 'class';
+CONST_      : 'const';
+CONTINUE_   : 'continue';
+COVARIANT_  : 'covariant';
+DEFAULT_    : 'default';
+DEFERRED_   : 'deferred';
+DO_         : 'do';
+DYNAMIC_    : 'dynamic';
+ELSE_       : 'else';
+ENUM_       : 'enum';
+EXPORT_     : 'export';
+EXTENDS_    : 'extends';
+EXTENSION_  : 'extension';
+EXTERNAL_   : 'external';
+FACTORY_    : 'factory';
+FALSE_      : 'false';
+FINAL_      : 'final';
+FINALLY_    : 'finally';
+FOR_        : 'for';
+FUNCTION_   : 'Function';
+GET_        : 'get';
+GTILDE_     : 'gtilde';
+HIDE_       : 'hide';
+IF_         : 'if';
+IMPLEMENTS_ : 'implements';
+IMPORT_     : 'import';
+IN_         : 'in';
+INTERFACE_  : 'interface';
+IS_         : 'is';
+LATE_       : 'late';
+LET_        : 'let';
+LIBRARY_    : 'library';
+MIXIN_      : 'mixin';
+NATIVE_     : 'native';
+NEW_        : 'new';
+NULL_       : 'null';
+OF_         : 'of';
+ON_         : 'on';
+OPERATOR_   : 'operator';
+PART_       : 'part';
+REQUIRED_   : 'required';
+RETHROW_    : 'rethrow';
+RETURN_     : 'return';
+// Dart 3 class modifiers
+SEALED_     : 'sealed';
+BASE_       : 'base';
+SET_        : 'set';
+SHOW_       : 'show';
+STATIC_     : 'static';
+SUPER_      : 'super';
+SWITCH_     : 'switch';
+SYNC_       : 'sync';
+THIS_       : 'this';
+THROW_      : 'throw';
+TRUE_       : 'true';
+TRY_        : 'try';
+TYPEDEF_    : 'typedef';
+VAR_        : 'var';
+VOID_       : 'void';
+WHILE_      : 'while';
+WITH_       : 'with';
+YIELD_      : 'yield';
+NUMBER      : DIGIT+ ( '.' DIGIT+)? EXPONENT? | '.' DIGIT+ EXPONENT?;
+HEX_NUMBER  : '0x' HEX_DIGIT+ | '0X' HEX_DIGIT+;
+SingleLineString:
+    StringDQ
+    | StringSQ
+    | 'r\'' ~('\'' | '\n' | '\r')* '\''
+    | 'r"' ~('"' | '\n' | '\r')* '"'
+;
+MultiLineString:
+    '"""' StringContentTDQ*? '"""'
+    | '\'\'\'' StringContentTSQ*? '\'\'\''
+    | 'r"""' (~'"' | '"' ~'"' | '""' ~'"')* '"""'
+    | 'r\'\'\'' (~'\'' | '\'' ~'\'' | '\'\'' ~'\'')* '\'\'\''
+;
+IDENTIFIER          : IDENTIFIER_START IDENTIFIER_PART*;
+WHITESPACE          : ( '\t' | ' ' | NEWLINE)+              -> skip;
+SINGLE_LINE_COMMENT : '//' ~[\r\n]*                         -> skip;
+MULTI_LINE_COMMENT  : '/*' ( MULTI_LINE_COMMENT | .)*? '*/' -> skip;
+fragment EXPONENT   : ( 'e' | 'E') ( '+' | '-')? DIGIT+;
+fragment HEX_DIGIT  : 'a' .. 'f' | 'A' .. 'F' | DIGIT;
+fragment StringDQ   : '"' StringContentDQ*? '"';
+fragment StringContentDQ:
+    ~('\\' | '"' | '\n' | '\r' | '$')
+    | '\\' ~('\n' | '\r')
+    | StringDQ
+    | '${' StringContentDQ*? '}'
+    | '$' { this.CheckNotOpenBrace() }?
+;
+fragment StringSQ: '\'' StringContentSQ*? '\'';
+fragment StringContentSQ:
+    ~('\\' | '\'' | '\n' | '\r' | '$')
+    | '\\' ~('\n' | '\r')
+    | StringSQ
+    | '${' StringContentSQ*? '}'
+    | '$' { this.CheckNotOpenBrace() }?
+;
+fragment StringContentTDQ : ~('\\' | '"') | '"' ~'"' | '""' ~'"';
+fragment StringContentTSQ : '\'' ~'\'' | '\'\'' ~'\'' | .;
+fragment ESCAPE_SEQUENCE:
+    '\n'
+    | '\r'
+    | '\\f'
+    | '\\b'
+    | '\t'
+    | '\\v'
+    | '\\x' HEX_DIGIT HEX_DIGIT
+    | '\\u' HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
+    | '\\u{' HEX_DIGIT_SEQUENCE '}'
+;
+fragment HEX_DIGIT_SEQUENCE : HEX_DIGIT HEX_DIGIT? HEX_DIGIT? HEX_DIGIT? HEX_DIGIT? HEX_DIGIT?;
+fragment NEWLINE            : '\n' | '\r' | '\r\n';
+fragment BUILT_IN_IDENTIFIER:
+    'abstract'
+    | 'as'
+    | 'covariant'
+    | 'deferred'
+    | 'dynamic'
+    | 'export'
+    | 'external'
+    | 'extension'
+    | 'factory'
+    | 'Function'
+    | 'get'
+    | 'implements'
+    | 'import'
+    | 'interface'
+    | 'late'
+    | 'library'
+    | 'mixin'
+    | 'operator'
+    | 'part'
+    | 'required'
+    | 'set'
+    | 'static'
+    | 'typedef'
+;
+fragment OTHER_IDENTIFIER           : 'async' | 'hide' | 'of' | 'on' | 'show' | 'sync' | 'await' | 'yield';
+fragment IDENTIFIER_NO_DOLLAR       : IDENTIFIER_START_NO_DOLLAR IDENTIFIER_PART_NO_DOLLAR*;
+fragment IDENTIFIER_START_NO_DOLLAR : LETTER | '_';
+fragment IDENTIFIER_PART_NO_DOLLAR  : IDENTIFIER_START_NO_DOLLAR | DIGIT;
+fragment IDENTIFIER_START           : IDENTIFIER_START_NO_DOLLAR | '$';
+fragment IDENTIFIER_PART            : IDENTIFIER_START | DIGIT;
+fragment LETTER                     : 'a' .. 'z' | 'A' .. 'Z';
+fragment DIGIT                      : '0' .. '9';