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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
import { correctIndentation } from "./indentation";
import { getGrip, getFront } from "./evaluation-result";
const UNAVAILABLE_GRIP = { unavailable: true };
/*
* wrap the expression input in a try/catch so that it can be safely
* evaluated.
*
* NOTE: we add line after the expression to protect against comments.
*/
export function wrapExpression(input) {
return correctIndentation(`
try {
${input}
} catch (e) {
e
}
`);
}
function isUnavailable(value) {
return (
value &&
!!value.isError &&
(value.class === "ReferenceError" || value.class === "TypeError")
);
}
/**
*
* @param {Object} expression: Expression item as stored in state.expressions in reducers/expressions.js
* @param {String} expression.input: evaluated expression string
* @param {Object} expression.value: evaluated expression result object as returned from ScriptCommand#execute
* @param {Object} expression.value.result: expression result, might be a primitive, a grip or a front
* @param {Object} expression.value.exception: expression result error, might be a primitive, a grip or a front
* @returns {Object} an object of the following shape:
* - expressionResultGrip: A primitive or a grip
* - expressionResultFront: An object front if it exists, or undefined
*/
export function getExpressionResultGripAndFront(expression) {
const { value } = expression;
if (!value) {
return { expressionResultGrip: UNAVAILABLE_GRIP };
}
const expressionResultReturn = value.exception || value.result;
const valueGrip = getGrip(expressionResultReturn);
if (!valueGrip || isUnavailable(valueGrip)) {
return { expressionResultGrip: UNAVAILABLE_GRIP };
}
if (valueGrip.isError) {
const { name, message } = valueGrip.preview;
return { expressionResultGrip: `${name}: ${message}` };
}
return {
expressionResultGrip: valueGrip,
expressionResultFront: getFront(expressionResultReturn),
};
}