svelte
Version:
Cybernetically enhanced web apps
452 lines (434 loc) • 14.6 kB
JavaScript
/** @import { ValidatedCompileOptions } from '#compiler' */
/** @import { Processed } from '../preprocess/public.js' */
/** @import { SourceMap } from 'magic-string' */
/** @import { Source } from '../preprocess/private.js' */
/** @import { DecodedSourceMap, SourceMapSegment, RawSourceMap } from '@ampproject/remapping' */
import remapping from '@ampproject/remapping';
import { push_array } from './push_array.js';
/**
* @param {string} s
*/
function last_line_length(s) {
return s.length - s.lastIndexOf('\n') - 1;
}
// mutate map in-place
/**
* @param {DecodedSourceMap} map
* @param {{ line: number; column: number; }} offset
* @param {number} source_index
*/
export function sourcemap_add_offset(map, offset, source_index) {
if (map.mappings.length == 0) return;
for (let line = 0; line < map.mappings.length; line++) {
const segment_list = map.mappings[line];
for (let segment = 0; segment < segment_list.length; segment++) {
const seg = segment_list[segment];
// shift only segments that belong to component source file
if (seg[1] === source_index) {
// also ensures that seg.length >= 4
// shift column if it points at the first line
if (seg[2] === 0) {
/** @type {any} */ (seg[3]) += offset.column;
}
// shift line
/** @type {any} */ (seg[2]) += offset.line;
}
}
}
}
/**
* @template T
* @param {T[]} this_table
* @param {T[]} other_table
* @returns {[T[], number[], boolean, boolean]}
*/
function merge_tables(this_table, other_table) {
const new_table = this_table.slice();
const idx_map = [];
other_table = other_table || [];
let val_changed = false;
for (const [other_idx, other_val] of other_table.entries()) {
const this_idx = this_table.indexOf(other_val);
if (this_idx >= 0) {
idx_map[other_idx] = this_idx;
} else {
const new_idx = new_table.length;
new_table[new_idx] = other_val;
idx_map[other_idx] = new_idx;
val_changed = true;
}
}
let idx_changed = val_changed;
if (val_changed) {
if (idx_map.find((val, idx) => val != idx) === undefined) {
// idx_map is identity map [0, 1, 2, 3, 4, ....]
idx_changed = false;
}
}
return [new_table, idx_map, val_changed, idx_changed];
}
const regex_line_token = /([^\w\s]|\s+)/g;
/** */
export class MappedCode {
/**
* @type {string}
*/
string = /** @type {any} */ (undefined);
/**
* @type {DecodedSourceMap}
*/
map = /** @type {any} */ (undefined);
/**
* @param {string} string
* @param {DecodedSourceMap | null} map
*/
constructor(string = '', map = null) {
this.string = string;
if (map) {
this.map = map;
} else {
this.map = {
version: 3,
mappings: [],
sources: [],
names: []
};
}
}
/**
* concat in-place (mutable), return this (chainable)
* will also mutate the `other` object
* @param {MappedCode} other
* @returns {MappedCode}
*/
concat(other) {
// noop: if one is empty, return the other
if (other.string == '') return this;
if (this.string == '') {
this.string = other.string;
this.map = other.map;
return this;
}
// compute last line length before mutating
const column_offset = last_line_length(this.string);
this.string += other.string;
const m1 = this.map;
const m2 = other.map;
if (m2.mappings.length == 0) return this;
// combine sources and names
const [sources, new_source_idx, sources_changed, sources_idx_changed] = merge_tables(
m1.sources,
m2.sources
);
const [names, new_name_idx, names_changed, names_idx_changed] = merge_tables(
m1.names,
m2.names
);
if (sources_changed) m1.sources = sources;
if (names_changed) m1.names = names;
// unswitched loops are faster
if (sources_idx_changed && names_idx_changed) {
for (let line = 0; line < m2.mappings.length; line++) {
const segment_list = m2.mappings[line];
for (let segment = 0; segment < segment_list.length; segment++) {
const seg = segment_list[segment];
// @ts-ignore
if (seg[1] >= 0) seg[1] = new_source_idx[seg[1]];
// @ts-ignore
if (seg[4] >= 0) seg[4] = new_name_idx[seg[4]];
}
}
} else if (sources_idx_changed) {
for (let line = 0; line < m2.mappings.length; line++) {
const segment_list = m2.mappings[line];
for (let segment = 0; segment < segment_list.length; segment++) {
const seg = segment_list[segment];
// @ts-ignore
if (seg[1] >= 0) seg[1] = new_source_idx[seg[1]];
}
}
} else if (names_idx_changed) {
for (let line = 0; line < m2.mappings.length; line++) {
const segment_list = m2.mappings[line];
for (let segment = 0; segment < segment_list.length; segment++) {
const seg = segment_list[segment];
// @ts-ignore
if (seg[4] >= 0) seg[4] = new_name_idx[seg[4]];
}
}
}
// combine the mappings
// combine
// 1. last line of first map
// 2. first line of second map
// columns of 2 must be shifted
if (m2.mappings.length > 0 && column_offset > 0) {
const first_line = m2.mappings[0];
for (let i = 0; i < first_line.length; i++) {
first_line[i][0] += column_offset;
}
}
// combine last line + first line
push_array(
m1.mappings[m1.mappings.length - 1],
/** @type {SourceMapSegment[]} */ (m2.mappings.shift())
);
// append other lines
push_array(m1.mappings, m2.mappings);
return this;
}
/**
* @static
* @param {string} string
* @param {DecodedSourceMap} [map]
* @returns {MappedCode}
*/
static from_processed(string, map) {
const line_count = string.split('\n').length;
if (map) {
// ensure that count of source map mappings lines
// is equal to count of generated code lines
// (some tools may produce less)
const missing_lines = line_count - map.mappings.length;
for (let i = 0; i < missing_lines; i++) {
map.mappings.push([]);
}
return new MappedCode(string, map);
}
if (string == '') return new MappedCode();
map = { version: 3, names: [], sources: [], mappings: [] };
// add empty SourceMapSegment[] for every line
for (let i = 0; i < line_count; i++) map.mappings.push([]);
return new MappedCode(string, map);
}
/**
* @static
* @param {Source} opts
* @returns {MappedCode}
*/
static from_source({ source, file_basename, get_location }) {
/**
* @type {{ line: number; column: number; }}
*/
let offset = get_location(0);
if (!offset) offset = { line: 0, column: 0 };
/**
* @type {DecodedSourceMap}
*/
const map = { version: 3, names: [], sources: [file_basename], mappings: [] };
if (source == '') return new MappedCode(source, map);
// we create a high resolution identity map here,
// we know that it will eventually be merged with svelte's map,
// at which stage the resolution will decrease.
const line_list = source.split('\n');
for (let line = 0; line < line_list.length; line++) {
map.mappings.push([]);
const token_list = line_list[line].split(regex_line_token);
for (let token = 0, column = 0; token < token_list.length; token++) {
if (token_list[token] == '') continue;
map.mappings[line].push([column, 0, offset.line + line, column]);
column += token_list[token].length;
}
}
// shift columns in first line
const segment_list = map.mappings[0];
for (let segment = 0; segment < segment_list.length; segment++) {
// @ts-ignore
segment_list[segment][3] += offset.column;
}
return new MappedCode(source, map);
}
}
// browser vs node.js
const b64enc =
typeof window !== 'undefined' && typeof btoa === 'function'
? /** @param {string} str */ (str) => btoa(unescape(encodeURIComponent(str)))
: /** @param {string} str */ (str) => Buffer.from(str).toString('base64');
const b64dec =
typeof window !== 'undefined' && typeof atob === 'function'
? atob
: /** @param {any} a */ (a) => Buffer.from(a, 'base64').toString();
/**
* @param {string} filename Basename of the input file
* @param {Array<DecodedSourceMap | RawSourceMap>} sourcemap_list
*/
export function combine_sourcemaps(filename, sourcemap_list) {
if (sourcemap_list.length == 0) return null;
let map_idx = 1;
const map =
sourcemap_list.slice(0, -1).find((m) => m.sources.length !== 1) === undefined
? remapping(
// use array interface
// only the oldest sourcemap can have multiple sources
sourcemap_list,
() => null,
true // skip optional field `sourcesContent`
)
: remapping(
// use loader interface
sourcemap_list[0], // last map
(sourcefile) => {
// TODO the equality check assumes that the preprocessor map has the input file as a relative path in sources,
// e.g. when the input file is `src/foo/bar.svelte`, then sources is expected to contain just `bar.svelte`.
// Therefore filename also needs to be the basename of the path. This feels brittle, investigate how we can
// harden this (without breaking other tooling that assumes this behavior).
if (sourcefile === filename && sourcemap_list[map_idx]) {
return sourcemap_list[map_idx++]; // idx 1, 2, ...
// bundle file = branch node
} else {
return null; // source file = leaf node
}
},
true
);
if (!map.file) delete map.file; // skip optional field `file`
// When source maps are combined and the leading map is empty, sources is not set.
// Add the filename to the empty array in this case.
// Further improvements to remapping may help address this as well https://github.com/ampproject/remapping/issues/116
if (!map.sources.length) map.sources = [filename];
return map;
}
/**
* @param {string} filename
* @param {SourceMap} svelte_map
* @param {string | DecodedSourceMap | RawSourceMap} preprocessor_map_input
* @returns {SourceMap}
*/
function apply_preprocessor_sourcemap(filename, svelte_map, preprocessor_map_input) {
if (!svelte_map || !preprocessor_map_input) return svelte_map;
const preprocessor_map =
typeof preprocessor_map_input === 'string'
? JSON.parse(preprocessor_map_input)
: preprocessor_map_input;
const result_map = combine_sourcemaps(filename, [svelte_map, preprocessor_map]);
// Svelte expects a SourceMap which includes toUrl and toString. Instead of wrapping our output in a class,
// we just tack on the extra properties.
Object.defineProperties(result_map, {
toString: {
enumerable: false,
value: function toString() {
return JSON.stringify(this);
}
},
toUrl: {
enumerable: false,
value: function toUrl() {
return 'data:application/json;charset=utf-8;base64,' + b64enc(this.toString());
}
}
});
return /** @type {any} */ (result_map);
}
const regex_data_uri = /data:(?:application|text)\/json;(?:charset[:=]\S+?;)?base64,(\S*)/;
// parse attached sourcemap in processed.code
/**
* @param {Processed} processed
* @param {'script' | 'style'} tag_name
* @returns {void}
*/
export function parse_attached_sourcemap(processed, tag_name) {
const r_in = '[#@]\\s*sourceMappingURL\\s*=\\s*(\\S*)';
const regex =
tag_name == 'script'
? new RegExp('(?://' + r_in + ')|(?:/\\*' + r_in + '\\s*\\*/)$')
: new RegExp('/\\*' + r_in + '\\s*\\*/$');
/**
* @param {any} message
*/
function log_warning(message) {
// code_start: help to find preprocessor
const code_start =
processed.code.length < 100 ? processed.code : processed.code.slice(0, 100) + ' [...]';
// eslint-disable-next-line no-console
console.warn(`warning: ${message}. processed.code = ${JSON.stringify(code_start)}`);
}
processed.code = processed.code.replace(regex, (_, match1, match2) => {
const map_url = tag_name == 'script' ? match1 || match2 : match1;
const map_data = (map_url.match(regex_data_uri) || [])[1];
if (map_data) {
// sourceMappingURL is data URL
if (processed.map) {
log_warning(
'Not implemented. ' +
'Found sourcemap in both processed.code and processed.map. ' +
'Please update your preprocessor to return only one sourcemap.'
);
// ignore attached sourcemap
return '';
}
processed.map = b64dec(map_data); // use attached sourcemap
return ''; // remove from processed.code
}
// sourceMappingURL is path or URL
if (!processed.map) {
log_warning(
`Found sourcemap path ${JSON.stringify(
map_url
)} in processed.code, but no sourcemap data. ` +
'Please update your preprocessor to return sourcemap data directly.'
);
}
// ignore sourcemap path
return ''; // remove from processed.code
});
}
/**
* @param {{ code: string, map: SourceMap}} result
* @param {ValidatedCompileOptions} options
* @param {string} source_name
*/
export function merge_with_preprocessor_map(result, options, source_name) {
if (options.sourcemap) {
const file_basename = get_basename(options.filename);
// The preprocessor map is expected to contain `sources: [basename_of_filename]`, but our own
// map may contain a different file name. Patch our map beforehand to align sources so merging
// with the preprocessor map works correctly.
result.map.sources = [file_basename];
result.map = apply_preprocessor_sourcemap(
file_basename,
result.map,
/** @type {any} */ (options.sourcemap)
);
// After applying the preprocessor map, we need to do the inverse and make the sources
// relative to the input file again in case the output code is in a different directory.
if (file_basename !== source_name) {
result.map.sources = result.map.sources.map(
/** @param {string} source */ (source) => get_relative_path(source_name, source)
);
}
}
}
/**
* @param {string} from
* @param {string} to
*/
function get_relative_path(from, to) {
// Don't use node's utils here to ensure the compiler is usable in a browser environment
const from_parts = from.split(/[/\\]/);
const to_parts = to.split(/[/\\]/);
from_parts.pop(); // get dirname
while (from_parts[0] === to_parts[0]) {
from_parts.shift();
to_parts.shift();
}
if (from_parts.length) {
let i = from_parts.length;
while (i--) from_parts[i] = '..';
}
return from_parts.concat(to_parts).join('/');
}
/**
* Like node's `basename`, but doesn't use it to ensure the compiler is usable in a browser environment
* @param {string} filename
*/
export function get_basename(filename) {
return /** @type {string} */ (filename.split(/[/\\]/).pop());
}
/**
* @param {string} filename
* @param {string | undefined} output_filename
* @param {string} fallback
*/
export function get_source_name(filename, output_filename, fallback) {
return output_filename ? get_relative_path(output_filename, filename) : get_basename(filename);
}