Various TSX parsing errors

[mjambon]

TSX errors 2020-10-02

These are errors obtained on .tsx files from public repositories and
one of our private repositories. These are obtained by running
make stat from lang/tsx, which uses the tsx dialect of
tree-sitter-typescript.

The number indicates the number of errors encountered.

Some of these errors are not specific to the TSX grammar. See #115 for other typescript errors.

TSX elements with type parameters

5

<Element<Type> />;
        ^^^^^^

The official typescript implementation supports it.

The error node reported by the tree-sitter parser starts from the beginning of the
file, typically covering a large region, making it hard to figure out
what's wrong.

PR: tree-sitter/tree-sitter-typescript#92

Type of the form A extends B ? C : D - conditional types

4

type a = b extends c ? d : e

Also a problem with pure typescript. See issue semgrep/semgrep#1969

Nested empty/anonymous tag/element

3

<Elt>
            <>
             ^

This is an element with no name. It's a shorthand for <React.Fragment>.
Same problem exists in tree-sitter-javascript.

PR (merged): tree-sitter/tree-sitter-javascript#139

Type arguments on function call

const PolicyTree: React.FC<Props> = ({ policy }) => {
  const [nodes, setNodes] = useState<ITreeNode[]>();
                                                 ^^^

node type: ERROR
children: [
  formal_parameters
  ";"
]

Tracked at semgrep/semgrep#1992

New lines in string literals representing attributes

2

<path
  d='a
     ^
     b'
 />;

PR: tree-sitter/tree-sitter-typescript#91

Optional keys (?)

2

export type ChampsPokemonProps = { [P in keyof Pokemon]?: any } & {
                                                       ^
    showNickname?: boolean;
    showGender?: boolean;
node type: ERROR
children: [
  "?"
]

Also a problem observed for pure typescript.

Tracked at tree-sitter/tree-sitter-typescript#98

keyof typeof

2

    return `${baseURL}${isShiny}/${isFemaleSpecific}${formatSpeciesName(
        species,
    )}${getIconFormeSuffix(forme as keyof typeof Forme)}.png`;
                                                 ^^^^^
};

Also a problem observed for pure typescript. Tracked at tree-sitter/tree-sitter-typescript#99

Abstract class (?)

import AppConfig from './AppConfig';

export default abstract class AppBootstrapper {
               ^^^^^^^^
    constructor() {
        RX.App.initialize(__DEV__, __DEV__);

See semgrep/semgrep#1995.

[mjambon]

Closing this because all the issues were simplified and either fixed or reported individually.