sucrase
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Super-fast alternative to Babel for when you can target modern JS runtimes
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JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = void 0;
var _base = _interopRequireDefault(require("./base"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/* eslint max-len: 0 */
/**
* Based on the comment attachment algorithm used in espree and estraverse.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
function last(stack) {
return stack[stack.length - 1];
}
class CommentsParser extends _base.default {
addComment(comment) {
if (this.filename) comment.loc.filename = this.filename;
this.state.trailingComments.push(comment);
this.state.leadingComments.push(comment);
}
processComment(node) {
if (node.type === "Program" && node.body.length > 0) return;
const stack = this.state.commentStack;
let firstChild, lastChild, trailingComments, i, j;
if (this.state.trailingComments.length > 0) {
// If the first comment in trailingComments comes after the
// current node, then we're good - all comments in the array will
// come after the node and so it's safe to add them as official
// trailingComments.
if (this.state.trailingComments[0].start >= node.end) {
trailingComments = this.state.trailingComments;
this.state.trailingComments = [];
} else {
// Otherwise, if the first comment doesn't come after the
// current node, that means we have a mix of leading and trailing
// comments in the array and that leadingComments contains the
// same items as trailingComments. Reset trailingComments to
// zero items and we'll handle this by evaluating leadingComments
// later.
this.state.trailingComments.length = 0;
}
} else {
if (stack.length > 0) {
const lastInStack = last(stack);
if (lastInStack.trailingComments && lastInStack.trailingComments[0].start >= node.end) {
trailingComments = lastInStack.trailingComments;
lastInStack.trailingComments = null;
}
}
} // Eating the stack.
if (stack.length > 0 && last(stack).start >= node.start) {
firstChild = stack.pop();
}
while (stack.length > 0 && last(stack).start >= node.start) {
lastChild = stack.pop();
}
if (!lastChild && firstChild) lastChild = firstChild; // Attach comments that follow a trailing comma on the last
// property in an object literal or a trailing comma in function arguments
// as trailing comments
if (firstChild && this.state.leadingComments.length > 0) {
const lastComment = last(this.state.leadingComments);
if (firstChild.type === "ObjectProperty") {
if (lastComment.start >= node.start) {
if (this.state.commentPreviousNode) {
for (j = 0; j < this.state.leadingComments.length; j++) {
if (this.state.leadingComments[j].end < this.state.commentPreviousNode.end) {
this.state.leadingComments.splice(j, 1);
j--;
}
}
if (this.state.leadingComments.length > 0) {
firstChild.trailingComments = this.state.leadingComments;
this.state.leadingComments = [];
}
}
}
} else if (node.type === "CallExpression" && node.arguments && node.arguments.length) {
const lastArg = last(node.arguments);
if (lastArg && lastComment.start >= lastArg.start && lastComment.end <= node.end) {
if (this.state.commentPreviousNode) {
if (this.state.leadingComments.length > 0) {
lastArg.trailingComments = this.state.leadingComments;
this.state.leadingComments = [];
}
}
}
}
}
if (lastChild) {
if (lastChild.leadingComments) {
if (lastChild !== node && lastChild.leadingComments.length > 0 && last(lastChild.leadingComments).end <= node.start) {
node.leadingComments = lastChild.leadingComments;
lastChild.leadingComments = null;
} else {
// A leading comment for an anonymous class had been stolen by its first ClassMethod,
// so this takes back the leading comment.
// See also: https://github.com/eslint/espree/issues/158
for (i = lastChild.leadingComments.length - 2; i >= 0; --i) {
if (lastChild.leadingComments[i].end <= node.start) {
node.leadingComments = lastChild.leadingComments.splice(0, i + 1);
break;
}
}
}
}
} else if (this.state.leadingComments.length > 0) {
if (last(this.state.leadingComments).end <= node.start) {
if (this.state.commentPreviousNode) {
for (j = 0; j < this.state.leadingComments.length; j++) {
if (this.state.leadingComments[j].end < this.state.commentPreviousNode.end) {
this.state.leadingComments.splice(j, 1);
j--;
}
}
}
if (this.state.leadingComments.length > 0) {
node.leadingComments = this.state.leadingComments;
this.state.leadingComments = [];
}
} else {
// https://github.com/eslint/espree/issues/2
//
// In special cases, such as return (without a value) and
// debugger, all comments will end up as leadingComments and
// will otherwise be eliminated. This step runs when the
// commentStack is empty and there are comments left
// in leadingComments.
//
// This loop figures out the stopping point between the actual
// leading and trailing comments by finding the location of the
// first comment that comes after the given node.
for (i = 0; i < this.state.leadingComments.length; i++) {
if (this.state.leadingComments[i].end > node.start) {
break;
}
} // Split the array based on the location of the first comment
// that comes after the node. Keep in mind that this could
// result in an empty array, and if so, the array must be
// deleted.
const leadingComments = this.state.leadingComments.slice(0, i);
node.leadingComments = leadingComments.length === 0 ? null : leadingComments; // Similarly, trailing comments are attached later. The variable
// must be reset to null if there are no trailing comments.
trailingComments = this.state.leadingComments.slice(i);
if (trailingComments.length === 0) {
trailingComments = null;
}
}
}
this.state.commentPreviousNode = node;
if (trailingComments) {
if (trailingComments.length && trailingComments[0].start >= node.start && last(trailingComments).end <= node.end) {
node.innerComments = trailingComments;
} else {
node.trailingComments = trailingComments;
}
}
stack.push(node);
}
}
exports.default = CommentsParser;