e68cc472c6
Make error messages from the lexing and parsing stages be a bit more helpful. If
provided with the input and a position, the error will display the error
position, and the nearby input with the error position underlined (yay combining
marks). Also, standardize the errors a bit (remove doubled "Error:" strings)
Test plan:
- Make sure the errors look totally sweet (before: {F15602}, after: {F15603})
- Trigger every error (that can be triggered) in Parser, Lexer, and buildTree
using the inputs:
`a^`
`a_`
`a^x^x`
`a_x_x`
`\color f`
`\blue `
`\Huge`
`\llap`
`\text`
`\dfrac`
`\dfrac{x}`
`\d`
`\blue{`
`\color{#f`
`{\Huge{x}}`
- See that the tests still work
Auditors: alpert
30 lines
942 B
JavaScript
30 lines
942 B
JavaScript
function ParseError(message, lexer, position) {
|
|
var error = "KaTeX parse error: " + message;
|
|
|
|
if (lexer !== undefined && position !== undefined) {
|
|
// If we have the input and a position, make the error a bit fancier
|
|
// Prepend some information
|
|
error += " at position " + position + ": ";
|
|
|
|
// Get the input
|
|
var input = lexer._input;
|
|
// Insert a combining underscore at the correct position
|
|
input = input.slice(0, position) + "\u0332" +
|
|
input.slice(position);
|
|
|
|
// Extract some context from the input and add it to the error
|
|
var begin = Math.max(0, position - 15);
|
|
var end = position + 15;
|
|
error += input.slice(begin, end);
|
|
}
|
|
|
|
var self = new Error(error);
|
|
self.name = "ParseError";
|
|
self.__proto__ = ParseError.prototype;
|
|
return self;
|
|
}
|
|
|
|
ParseError.prototype.__proto__ = Error.prototype;
|
|
|
|
module.exports = ParseError;
|