Dom: model JS expressions/statements in QmlDom and add qmlls (find usages, go to definition, ...) support for them

QmlJSScope supports js scopes and usages, it should be cleanly integrated in the Dom, to give access to declarations and usages in QML code. As QQmlJSScope itself is not enough to implement all the LSP-features, model JS statements and expressions in the DOM to complement its information.

For example, implementing findUsages in qmlls cannot be done only with QQmlJSScope's, as the semantic scopes contain the definitions of JS identifiers but not their usages in the code. Also, the current JS-reformatting works directly on the AST-classes used by the Parser and the DOM for JS statements/expressions might leave a door open to move the reformatting implementation inside the DOM JS classes for later...

Also implement support (or at least add tests) for

• find usages
• go to definition
• go to type definition
• completions
• rename usage
  on the newly introduced dom representations!

Mostly, all of the JS support for classes can be left out for now, assuming that most of the users are using QML objects instead.

List of statements/expressions to model in the DOM:

done

to be done

do not do

in progress

• PrimaryExpressions (https://262.ecma-international.org/7.0/#sec-primary-expression)
      * this
      * Identifier QTBUG-113208
      * Literal
            * NullLiteral
            * BooleanLiteral
            * NumericLiteral QTBUG-113208
            * StringLiteral QTBUG-113208
      * ArrayLiteral (https://codereview.qt-project.org/c/qt/qtdeclarative/+/479913)
      * ObjectLiteral (https://codereview.qt-project.org/c/qt/qtdeclarative/+/479913)
      * FunctionExpression
      * ClassExpression (not needed for now)
      * GeneratorExpression
      * RegularExpressionLiteral
      * TemplateLiteral
      * CoverParenthesizedExpressionAndArrowParameterList
  • this is being parsed as AST::FormalParameterList or
  • AST::NestedExpression for expressions inside of `()` brackets
• Left-Hand-Side expressions (https://262.ecma-international.org/7.0/#sec-left-hand-side-expressions)
  • Property Accessors
    • Bracket expressions (`id[something]`) QTBUG-113381
    • Field Member access (`id.field`)   QTBUG-113381
  • New expressions (`new Something ()`)
  • Function calls

• • • inclusive ArgumentLists, passed to the calls (https://codereview.qt-project.org/c/qt/qtdeclarative/+/479913)
  • Template Literal
  • Super property
  • Meta Property (new.target support)
• UpdateExpressions (https://262.ecma-international.org/7.0/#sec-update-expressions)
  • pre/post increment/decrements
• Unary Operators (https://262.ecma-international.org/7.0/#sec-unary-operators)
  • delete/void/typeof/+/-/~/!
• BinaryExpressions:

• • Exponentiation operator (https://262.ecma-international.org/7.0/#sec-exp-operator )
  • Multiplicative operators (https://262.ecma-international.org/7.0/#sec-multiplicative-operators )
  • Additive Operators (https://262.ecma-international.org/7.0/#sec-additive-operators )
  • Bitwise Shifts (https://262.ecma-international.org/7.0/#sec-bitwise-shift-operators )
  • Relational operators (https://262.ecma-international.org/7.0/#sec-relational-operators )
  • Equality Operators ( https://262.ecma-international.org/7.0/#sec-equality-operators )
  • Binary bitwise operators (https://262.ecma-international.org/7.0/#sec-binary-bitwise-operators )
  • Binary logical operators (https://262.ecma-international.org/7.0/#sec-binary-logical-operators )
  • Assignment Operators (https://262.ecma-international.org/7.0/#sec-assignment-operators )
  • Comma operators (https://262.ecma-international.org/7.0/#sec-comma-operator )

• • • note: this is being parsed as an "AST::Expression"!!!
• Conditional operator (https://262.ecma-international.org/7.0/#sec-conditional-operator )
• Statements and Declarations (https://262.ecma-international.org/7.0/#sec-ecmascript-language-statements-and-declarations)
      * BlockStatement QTBUG-113208
      * VariableStatement QTBUG-113328
      * EmptyStatement
      * ExpressionStatement QTBUG-113208
      * IfStatement QTBUG-113208
      * BreakableStatement https://bugreports.qt.io/browse/QTBUG-113334
            * SwitchStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/481423
            * IterationStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/480658
                 * For-loops (to be split further in foreach, for, ....)
                 * Do-while loops
                 * while loops
      * ContinueStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/522977/4
      * BreakStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/522977/4
      * ReturnStatement QTBUG-113208
      * WithStatement
      * LabelledStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/522979/5
      * ThrowStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/522572/5
      * TryStatement done in https://codereview.qt-project.org/c/qt/qtdeclarative/+/520284/5
      * DebuggerStatement
• Functions and Classes (https://262.ecma-international.org/7.0/#sec-ecmascript-language-functions-and-classes)
      * Function Definitions
      * Arrow Function Definitions
      * Method Definitions (not needed now)
      * Generator Function Definitions
      * Class Definitions   (not needed now)