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- var assert = require("assert");
- var sourceMap = require("source-map");
- var normalizeOptions = require("./options").normalize;
- var secretKey = require("private").makeUniqueKey();
- var types = require("./types");
- var isString = types.builtInTypes.string;
- var comparePos = require("./util").comparePos;
- var Mapping = require("./mapping");
-
- // Goals:
- // 1. Minimize new string creation.
- // 2. Keep (de)identation O(lines) time.
- // 3. Permit negative indentations.
- // 4. Enforce immutability.
- // 5. No newline characters.
-
- function getSecret(lines) {
- return lines[secretKey];
- }
-
- function Lines(infos, sourceFileName) {
- assert.ok(this instanceof Lines);
- assert.ok(infos.length > 0);
-
- if (sourceFileName) {
- isString.assert(sourceFileName);
- } else {
- sourceFileName = null;
- }
-
- Object.defineProperty(this, secretKey, {
- value: {
- infos: infos,
- mappings: [],
- name: sourceFileName,
- cachedSourceMap: null
- }
- });
-
- if (sourceFileName) {
- getSecret(this).mappings.push(new Mapping(this, {
- start: this.firstPos(),
- end: this.lastPos()
- }));
- }
- }
-
- // Exposed for instanceof checks. The fromString function should be used
- // to create new Lines objects.
- exports.Lines = Lines;
- var Lp = Lines.prototype;
-
- // These properties used to be assigned to each new object in the Lines
- // constructor, but we can more efficiently stuff them into the secret and
- // let these lazy accessors compute their values on-the-fly.
- Object.defineProperties(Lp, {
- length: {
- get: function() {
- return getSecret(this).infos.length;
- }
- },
-
- name: {
- get: function() {
- return getSecret(this).name;
- }
- }
- });
-
- function copyLineInfo(info) {
- return {
- line: info.line,
- indent: info.indent,
- locked: info.locked,
- sliceStart: info.sliceStart,
- sliceEnd: info.sliceEnd
- };
- }
-
- var fromStringCache = {};
- var hasOwn = fromStringCache.hasOwnProperty;
- var maxCacheKeyLen = 10;
-
- function countSpaces(spaces, tabWidth) {
- var count = 0;
- var len = spaces.length;
-
- for (var i = 0; i < len; ++i) {
- switch (spaces.charCodeAt(i)) {
- case 9: // '\t'
- assert.strictEqual(typeof tabWidth, "number");
- assert.ok(tabWidth > 0);
-
- var next = Math.ceil(count / tabWidth) * tabWidth;
- if (next === count) {
- count += tabWidth;
- } else {
- count = next;
- }
-
- break;
-
- case 11: // '\v'
- case 12: // '\f'
- case 13: // '\r'
- case 0xfeff: // zero-width non-breaking space
- // These characters contribute nothing to indentation.
- break;
-
- case 32: // ' '
- default: // Treat all other whitespace like ' '.
- count += 1;
- break;
- }
- }
-
- return count;
- }
- exports.countSpaces = countSpaces;
-
- var leadingSpaceExp = /^\s*/;
-
- // As specified here: http://www.ecma-international.org/ecma-262/6.0/#sec-line-terminators
- var lineTerminatorSeqExp =
- /\u000D\u000A|\u000D(?!\u000A)|\u000A|\u2028|\u2029/;
-
- /**
- * @param {Object} options - Options object that configures printing.
- */
- function fromString(string, options) {
- if (string instanceof Lines)
- return string;
-
- string += "";
-
- var tabWidth = options && options.tabWidth;
- var tabless = string.indexOf("\t") < 0;
- var locked = !! (options && options.locked);
- var cacheable = !options && tabless && (string.length <= maxCacheKeyLen);
-
- assert.ok(tabWidth || tabless, "No tab width specified but encountered tabs in string\n" + string);
-
- if (cacheable && hasOwn.call(fromStringCache, string))
- return fromStringCache[string];
-
- var lines = new Lines(string.split(lineTerminatorSeqExp).map(function(line) {
- var spaces = leadingSpaceExp.exec(line)[0];
- return {
- line: line,
- indent: countSpaces(spaces, tabWidth),
- // Boolean indicating whether this line can be reindented.
- locked: locked,
- sliceStart: spaces.length,
- sliceEnd: line.length
- };
- }), normalizeOptions(options).sourceFileName);
-
- if (cacheable)
- fromStringCache[string] = lines;
-
- return lines;
- }
- exports.fromString = fromString;
-
- function isOnlyWhitespace(string) {
- return !/\S/.test(string);
- }
-
- Lp.toString = function(options) {
- return this.sliceString(this.firstPos(), this.lastPos(), options);
- };
-
- Lp.getSourceMap = function(sourceMapName, sourceRoot) {
- if (!sourceMapName) {
- // Although we could make up a name or generate an anonymous
- // source map, instead we assume that any consumer who does not
- // provide a name does not actually want a source map.
- return null;
- }
-
- var targetLines = this;
-
- function updateJSON(json) {
- json = json || {};
-
- isString.assert(sourceMapName);
- json.file = sourceMapName;
-
- if (sourceRoot) {
- isString.assert(sourceRoot);
- json.sourceRoot = sourceRoot;
- }
-
- return json;
- }
-
- var secret = getSecret(targetLines);
- if (secret.cachedSourceMap) {
- // Since Lines objects are immutable, we can reuse any source map
- // that was previously generated. Nevertheless, we return a new
- // JSON object here to protect the cached source map from outside
- // modification.
- return updateJSON(secret.cachedSourceMap.toJSON());
- }
-
- var smg = new sourceMap.SourceMapGenerator(updateJSON());
- var sourcesToContents = {};
-
- secret.mappings.forEach(function(mapping) {
- var sourceCursor = mapping.sourceLines.skipSpaces(
- mapping.sourceLoc.start
- ) || mapping.sourceLines.lastPos();
-
- var targetCursor = targetLines.skipSpaces(
- mapping.targetLoc.start
- ) || targetLines.lastPos();
-
- while (comparePos(sourceCursor, mapping.sourceLoc.end) < 0 &&
- comparePos(targetCursor, mapping.targetLoc.end) < 0) {
-
- var sourceChar = mapping.sourceLines.charAt(sourceCursor);
- var targetChar = targetLines.charAt(targetCursor);
- assert.strictEqual(sourceChar, targetChar);
-
- var sourceName = mapping.sourceLines.name;
-
- // Add mappings one character at a time for maximum resolution.
- smg.addMapping({
- source: sourceName,
- original: { line: sourceCursor.line,
- column: sourceCursor.column },
- generated: { line: targetCursor.line,
- column: targetCursor.column }
- });
-
- if (!hasOwn.call(sourcesToContents, sourceName)) {
- var sourceContent = mapping.sourceLines.toString();
- smg.setSourceContent(sourceName, sourceContent);
- sourcesToContents[sourceName] = sourceContent;
- }
-
- targetLines.nextPos(targetCursor, true);
- mapping.sourceLines.nextPos(sourceCursor, true);
- }
- });
-
- secret.cachedSourceMap = smg;
-
- return smg.toJSON();
- };
-
- Lp.bootstrapCharAt = function(pos) {
- assert.strictEqual(typeof pos, "object");
- assert.strictEqual(typeof pos.line, "number");
- assert.strictEqual(typeof pos.column, "number");
-
- var line = pos.line,
- column = pos.column,
- strings = this.toString().split(lineTerminatorSeqExp),
- string = strings[line - 1];
-
- if (typeof string === "undefined")
- return "";
-
- if (column === string.length &&
- line < strings.length)
- return "\n";
-
- if (column >= string.length)
- return "";
-
- return string.charAt(column);
- };
-
- Lp.charAt = function(pos) {
- assert.strictEqual(typeof pos, "object");
- assert.strictEqual(typeof pos.line, "number");
- assert.strictEqual(typeof pos.column, "number");
-
- var line = pos.line,
- column = pos.column,
- secret = getSecret(this),
- infos = secret.infos,
- info = infos[line - 1],
- c = column;
-
- if (typeof info === "undefined" || c < 0)
- return "";
-
- var indent = this.getIndentAt(line);
- if (c < indent)
- return " ";
-
- c += info.sliceStart - indent;
-
- if (c === info.sliceEnd &&
- line < this.length)
- return "\n";
-
- if (c >= info.sliceEnd)
- return "";
-
- return info.line.charAt(c);
- };
-
- Lp.stripMargin = function(width, skipFirstLine) {
- if (width === 0)
- return this;
-
- assert.ok(width > 0, "negative margin: " + width);
-
- if (skipFirstLine && this.length === 1)
- return this;
-
- var secret = getSecret(this);
-
- var lines = new Lines(secret.infos.map(function(info, i) {
- if (info.line && (i > 0 || !skipFirstLine)) {
- info = copyLineInfo(info);
- info.indent = Math.max(0, info.indent - width);
- }
- return info;
- }));
-
- if (secret.mappings.length > 0) {
- var newMappings = getSecret(lines).mappings;
- assert.strictEqual(newMappings.length, 0);
- secret.mappings.forEach(function(mapping) {
- newMappings.push(mapping.indent(width, skipFirstLine, true));
- });
- }
-
- return lines;
- };
-
- Lp.indent = function(by) {
- if (by === 0)
- return this;
-
- var secret = getSecret(this);
-
- var lines = new Lines(secret.infos.map(function(info) {
- if (info.line && ! info.locked) {
- info = copyLineInfo(info);
- info.indent += by;
- }
- return info
- }));
-
- if (secret.mappings.length > 0) {
- var newMappings = getSecret(lines).mappings;
- assert.strictEqual(newMappings.length, 0);
- secret.mappings.forEach(function(mapping) {
- newMappings.push(mapping.indent(by));
- });
- }
-
- return lines;
- };
-
- Lp.indentTail = function(by) {
- if (by === 0)
- return this;
-
- if (this.length < 2)
- return this;
-
- var secret = getSecret(this);
-
- var lines = new Lines(secret.infos.map(function(info, i) {
- if (i > 0 && info.line && ! info.locked) {
- info = copyLineInfo(info);
- info.indent += by;
- }
-
- return info;
- }));
-
- if (secret.mappings.length > 0) {
- var newMappings = getSecret(lines).mappings;
- assert.strictEqual(newMappings.length, 0);
- secret.mappings.forEach(function(mapping) {
- newMappings.push(mapping.indent(by, true));
- });
- }
-
- return lines;
- };
-
- Lp.lockIndentTail = function () {
- if (this.length < 2) {
- return this;
- }
-
- var infos = getSecret(this).infos;
-
- return new Lines(infos.map(function (info, i) {
- info = copyLineInfo(info);
- info.locked = i > 0;
- return info;
- }));
- };
-
- Lp.getIndentAt = function(line) {
- assert.ok(line >= 1, "no line " + line + " (line numbers start from 1)");
- var secret = getSecret(this),
- info = secret.infos[line - 1];
- return Math.max(info.indent, 0);
- };
-
- Lp.guessTabWidth = function() {
- var secret = getSecret(this);
- if (hasOwn.call(secret, "cachedTabWidth")) {
- return secret.cachedTabWidth;
- }
-
- var counts = []; // Sparse array.
- var lastIndent = 0;
-
- for (var line = 1, last = this.length; line <= last; ++line) {
- var info = secret.infos[line - 1];
- var sliced = info.line.slice(info.sliceStart, info.sliceEnd);
-
- // Whitespace-only lines don't tell us much about the likely tab
- // width of this code.
- if (isOnlyWhitespace(sliced)) {
- continue;
- }
-
- var diff = Math.abs(info.indent - lastIndent);
- counts[diff] = ~~counts[diff] + 1;
- lastIndent = info.indent;
- }
-
- var maxCount = -1;
- var result = 2;
-
- for (var tabWidth = 1;
- tabWidth < counts.length;
- tabWidth += 1) {
- if (hasOwn.call(counts, tabWidth) &&
- counts[tabWidth] > maxCount) {
- maxCount = counts[tabWidth];
- result = tabWidth;
- }
- }
-
- return secret.cachedTabWidth = result;
- };
-
- Lp.isOnlyWhitespace = function() {
- return isOnlyWhitespace(this.toString());
- };
-
- Lp.isPrecededOnlyByWhitespace = function(pos) {
- var secret = getSecret(this);
- var info = secret.infos[pos.line - 1];
- var indent = Math.max(info.indent, 0);
-
- var diff = pos.column - indent;
- if (diff <= 0) {
- // If pos.column does not exceed the indentation amount, then
- // there must be only whitespace before it.
- return true;
- }
-
- var start = info.sliceStart;
- var end = Math.min(start + diff, info.sliceEnd);
- var prefix = info.line.slice(start, end);
-
- return isOnlyWhitespace(prefix);
- };
-
- Lp.getLineLength = function(line) {
- var secret = getSecret(this),
- info = secret.infos[line - 1];
- return this.getIndentAt(line) + info.sliceEnd - info.sliceStart;
- };
-
- Lp.nextPos = function(pos, skipSpaces) {
- var l = Math.max(pos.line, 0),
- c = Math.max(pos.column, 0);
-
- if (c < this.getLineLength(l)) {
- pos.column += 1;
-
- return skipSpaces
- ? !!this.skipSpaces(pos, false, true)
- : true;
- }
-
- if (l < this.length) {
- pos.line += 1;
- pos.column = 0;
-
- return skipSpaces
- ? !!this.skipSpaces(pos, false, true)
- : true;
- }
-
- return false;
- };
-
- Lp.prevPos = function(pos, skipSpaces) {
- var l = pos.line,
- c = pos.column;
-
- if (c < 1) {
- l -= 1;
-
- if (l < 1)
- return false;
-
- c = this.getLineLength(l);
-
- } else {
- c = Math.min(c - 1, this.getLineLength(l));
- }
-
- pos.line = l;
- pos.column = c;
-
- return skipSpaces
- ? !!this.skipSpaces(pos, true, true)
- : true;
- };
-
- Lp.firstPos = function() {
- // Trivial, but provided for completeness.
- return { line: 1, column: 0 };
- };
-
- Lp.lastPos = function() {
- return {
- line: this.length,
- column: this.getLineLength(this.length)
- };
- };
-
- Lp.skipSpaces = function(pos, backward, modifyInPlace) {
- if (pos) {
- pos = modifyInPlace ? pos : {
- line: pos.line,
- column: pos.column
- };
- } else if (backward) {
- pos = this.lastPos();
- } else {
- pos = this.firstPos();
- }
-
- if (backward) {
- while (this.prevPos(pos)) {
- if (!isOnlyWhitespace(this.charAt(pos)) &&
- this.nextPos(pos)) {
- return pos;
- }
- }
-
- return null;
-
- } else {
- while (isOnlyWhitespace(this.charAt(pos))) {
- if (!this.nextPos(pos)) {
- return null;
- }
- }
-
- return pos;
- }
- };
-
- Lp.trimLeft = function() {
- var pos = this.skipSpaces(this.firstPos(), false, true);
- return pos ? this.slice(pos) : emptyLines;
- };
-
- Lp.trimRight = function() {
- var pos = this.skipSpaces(this.lastPos(), true, true);
- return pos ? this.slice(this.firstPos(), pos) : emptyLines;
- };
-
- Lp.trim = function() {
- var start = this.skipSpaces(this.firstPos(), false, true);
- if (start === null)
- return emptyLines;
-
- var end = this.skipSpaces(this.lastPos(), true, true);
- assert.notStrictEqual(end, null);
-
- return this.slice(start, end);
- };
-
- Lp.eachPos = function(callback, startPos, skipSpaces) {
- var pos = this.firstPos();
-
- if (startPos) {
- pos.line = startPos.line,
- pos.column = startPos.column
- }
-
- if (skipSpaces && !this.skipSpaces(pos, false, true)) {
- return; // Encountered nothing but spaces.
- }
-
- do callback.call(this, pos);
- while (this.nextPos(pos, skipSpaces));
- };
-
- Lp.bootstrapSlice = function(start, end) {
- var strings = this.toString().split(
- lineTerminatorSeqExp
- ).slice(
- start.line - 1,
- end.line
- );
-
- strings.push(strings.pop().slice(0, end.column));
- strings[0] = strings[0].slice(start.column);
-
- return fromString(strings.join("\n"));
- };
-
- Lp.slice = function(start, end) {
- if (!end) {
- if (!start) {
- // The client seems to want a copy of this Lines object, but
- // Lines objects are immutable, so it's perfectly adequate to
- // return the same object.
- return this;
- }
-
- // Slice to the end if no end position was provided.
- end = this.lastPos();
- }
-
- var secret = getSecret(this);
- var sliced = secret.infos.slice(start.line - 1, end.line);
-
- if (start.line === end.line) {
- sliced[0] = sliceInfo(sliced[0], start.column, end.column);
- } else {
- assert.ok(start.line < end.line);
- sliced[0] = sliceInfo(sliced[0], start.column);
- sliced.push(sliceInfo(sliced.pop(), 0, end.column));
- }
-
- var lines = new Lines(sliced);
-
- if (secret.mappings.length > 0) {
- var newMappings = getSecret(lines).mappings;
- assert.strictEqual(newMappings.length, 0);
- secret.mappings.forEach(function(mapping) {
- var sliced = mapping.slice(this, start, end);
- if (sliced) {
- newMappings.push(sliced);
- }
- }, this);
- }
-
- return lines;
- };
-
- function sliceInfo(info, startCol, endCol) {
- var sliceStart = info.sliceStart;
- var sliceEnd = info.sliceEnd;
- var indent = Math.max(info.indent, 0);
- var lineLength = indent + sliceEnd - sliceStart;
-
- if (typeof endCol === "undefined") {
- endCol = lineLength;
- }
-
- startCol = Math.max(startCol, 0);
- endCol = Math.min(endCol, lineLength);
- endCol = Math.max(endCol, startCol);
-
- if (endCol < indent) {
- indent = endCol;
- sliceEnd = sliceStart;
- } else {
- sliceEnd -= lineLength - endCol;
- }
-
- lineLength = endCol;
- lineLength -= startCol;
-
- if (startCol < indent) {
- indent -= startCol;
- } else {
- startCol -= indent;
- indent = 0;
- sliceStart += startCol;
- }
-
- assert.ok(indent >= 0);
- assert.ok(sliceStart <= sliceEnd);
- assert.strictEqual(lineLength, indent + sliceEnd - sliceStart);
-
- if (info.indent === indent &&
- info.sliceStart === sliceStart &&
- info.sliceEnd === sliceEnd) {
- return info;
- }
-
- return {
- line: info.line,
- indent: indent,
- // A destructive slice always unlocks indentation.
- locked: false,
- sliceStart: sliceStart,
- sliceEnd: sliceEnd
- };
- }
-
- Lp.bootstrapSliceString = function(start, end, options) {
- return this.slice(start, end).toString(options);
- };
-
- Lp.sliceString = function(start, end, options) {
- if (!end) {
- if (!start) {
- // The client seems to want a copy of this Lines object, but
- // Lines objects are immutable, so it's perfectly adequate to
- // return the same object.
- return this;
- }
-
- // Slice to the end if no end position was provided.
- end = this.lastPos();
- }
-
- options = normalizeOptions(options);
-
- var infos = getSecret(this).infos;
- var parts = [];
- var tabWidth = options.tabWidth;
-
- for (var line = start.line; line <= end.line; ++line) {
- var info = infos[line - 1];
-
- if (line === start.line) {
- if (line === end.line) {
- info = sliceInfo(info, start.column, end.column);
- } else {
- info = sliceInfo(info, start.column);
- }
- } else if (line === end.line) {
- info = sliceInfo(info, 0, end.column);
- }
-
- var indent = Math.max(info.indent, 0);
-
- var before = info.line.slice(0, info.sliceStart);
- if (options.reuseWhitespace &&
- isOnlyWhitespace(before) &&
- countSpaces(before, options.tabWidth) === indent) {
- // Reuse original spaces if the indentation is correct.
- parts.push(info.line.slice(0, info.sliceEnd));
- continue;
- }
-
- var tabs = 0;
- var spaces = indent;
-
- if (options.useTabs) {
- tabs = Math.floor(indent / tabWidth);
- spaces -= tabs * tabWidth;
- }
-
- var result = "";
-
- if (tabs > 0) {
- result += new Array(tabs + 1).join("\t");
- }
-
- if (spaces > 0) {
- result += new Array(spaces + 1).join(" ");
- }
-
- result += info.line.slice(info.sliceStart, info.sliceEnd);
-
- parts.push(result);
- }
-
- return parts.join(options.lineTerminator);
- };
-
- Lp.isEmpty = function() {
- return this.length < 2 && this.getLineLength(1) < 1;
- };
-
- Lp.join = function(elements) {
- var separator = this;
- var separatorSecret = getSecret(separator);
- var infos = [];
- var mappings = [];
- var prevInfo;
-
- function appendSecret(secret) {
- if (secret === null)
- return;
-
- if (prevInfo) {
- var info = secret.infos[0];
- var indent = new Array(info.indent + 1).join(" ");
- var prevLine = infos.length;
- var prevColumn = Math.max(prevInfo.indent, 0) +
- prevInfo.sliceEnd - prevInfo.sliceStart;
-
- prevInfo.line = prevInfo.line.slice(
- 0, prevInfo.sliceEnd) + indent + info.line.slice(
- info.sliceStart, info.sliceEnd);
-
- // If any part of a line is indentation-locked, the whole line
- // will be indentation-locked.
- prevInfo.locked = prevInfo.locked || info.locked;
-
- prevInfo.sliceEnd = prevInfo.line.length;
-
- if (secret.mappings.length > 0) {
- secret.mappings.forEach(function(mapping) {
- mappings.push(mapping.add(prevLine, prevColumn));
- });
- }
-
- } else if (secret.mappings.length > 0) {
- mappings.push.apply(mappings, secret.mappings);
- }
-
- secret.infos.forEach(function(info, i) {
- if (!prevInfo || i > 0) {
- prevInfo = copyLineInfo(info);
- infos.push(prevInfo);
- }
- });
- }
-
- function appendWithSeparator(secret, i) {
- if (i > 0)
- appendSecret(separatorSecret);
- appendSecret(secret);
- }
-
- elements.map(function(elem) {
- var lines = fromString(elem);
- if (lines.isEmpty())
- return null;
- return getSecret(lines);
- }).forEach(separator.isEmpty()
- ? appendSecret
- : appendWithSeparator);
-
- if (infos.length < 1)
- return emptyLines;
-
- var lines = new Lines(infos);
-
- getSecret(lines).mappings = mappings;
-
- return lines;
- };
-
- exports.concat = function(elements) {
- return emptyLines.join(elements);
- };
-
- Lp.concat = function(other) {
- var args = arguments,
- list = [this];
- list.push.apply(list, args);
- assert.strictEqual(list.length, args.length + 1);
- return emptyLines.join(list);
- };
-
- // The emptyLines object needs to be created all the way down here so that
- // Lines.prototype will be fully populated.
- var emptyLines = fromString("");
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