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6abff73 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 | // Copyright (c) Microsoft Corporation. All rights reserved. Licensed under the MIT license.
// See LICENSE in the project root for license information.
/**
* Efficiently references a range of text from a string buffer.
*/
export class TextRange {
constructor(buffer, pos, end) {
this.buffer = buffer;
this.pos = pos;
this.end = end;
this._validateBounds();
}
/**
* Constructs a TextRange that corresponds to an entire string object.
*/
static fromString(buffer) {
return new TextRange(buffer, 0, buffer.length);
}
/**
* Constructs a TextRange that corresponds to an entire string object.
*/
static fromStringRange(buffer, pos, end) {
return new TextRange(buffer, pos, end);
}
/**
* Returns the length of the text range.
* @remarks
* This value is calculated as the `end` property minus the `pos` property.
*/
get length() {
return this.end - this.pos;
}
/**
* Constructs a TextRange that corresponds to a different range of an existing buffer.
*/
getNewRange(pos, end) {
return new TextRange(this.buffer, pos, end);
}
/**
* Returns true if the length of the range is zero. Note that the object reference may not
* be equal to `TextRange.empty`, and the buffer may be different.
*/
isEmpty() {
return this.pos === this.end;
}
/**
* Returns the range from the associated string buffer.
*/
toString() {
return this.buffer.substring(this.pos, this.end);
}
/**
* Returns a debugging dump of the range, indicated via custom delimiters.
* @remarks
* For example if the delimiters are "[" and "]", and the range is 3..5 inside "1234567",
* then the output would be "12[345]67".
*/
getDebugDump(posDelimiter, endDelimiter) {
return (this.buffer.substring(0, this.pos) +
posDelimiter +
this.buffer.substring(this.pos, this.end) +
endDelimiter +
this.buffer.substring(this.end));
}
/**
* Calculates the line and column number for the specified offset into the buffer.
*
* @remarks
* This is a potentially expensive operation.
*
* @param index - an integer offset
* @param buffer - the buffer
*/
getLocation(index) {
if (index < 0 || index > this.buffer.length) {
// No match
return { line: 0, column: 0 };
}
// TODO: Consider caching or optimizing this somehow
let line = 1;
let column = 1;
let currentIndex = 0;
while (currentIndex < index) {
const current = this.buffer[currentIndex];
++currentIndex;
if (current === '\r') {
// CR
// Ignore '\r' and assume it will always have an accompanying '\n'
continue;
}
if (current === '\n') {
// LF
++line;
column = 1;
}
else {
// NOTE: For consistency with the TypeScript compiler, a tab character is assumed
// to advance by one column
++column;
}
}
return { line, column };
}
_validateBounds() {
if (this.pos < 0) {
throw new Error('TextRange.pos cannot be negative');
}
if (this.end < 0) {
throw new Error('TextRange.end cannot be negative');
}
if (this.end < this.pos) {
throw new Error('TextRange.end cannot be smaller than TextRange.pos');
}
if (this.pos > this.buffer.length) {
throw new Error('TextRange.pos cannot exceed the associated text buffer length');
}
if (this.end > this.buffer.length) {
throw new Error('TextRange.end cannot exceed the associated text buffer length');
}
}
}
/**
* Used to represent an empty or unknown range.
*/
TextRange.empty = new TextRange('', 0, 0);
//# sourceMappingURL=TextRange.js.map |