1 files changed, 116 insertions, 0 deletions
diff --git a/node_modules/webpack-sources/lib/helpers/readMappings.js b/node_modules/webpack-sources/lib/helpers/readMappings.js
new file mode 100644
index 00000000..31cb48d2
--- /dev/null
+++ b/node_modules/webpack-sources/lib/helpers/readMappings.js
@@ -0,0 +1,116 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+
+"use strict";
+
+const ALPHABET =
+	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+const CONTINUATION_BIT = 0x20;
+const END_SEGMENT_BIT = 0x40;
+const NEXT_LINE = END_SEGMENT_BIT | 0x01;
+const INVALID = END_SEGMENT_BIT | 0x02;
+const DATA_MASK = 0x1f;
+
+const ccToValue = new Uint8Array("z".charCodeAt(0) + 1);
+{
+	ccToValue.fill(INVALID);
+	for (let i = 0; i < ALPHABET.length; i++) {
+		ccToValue[ALPHABET.charCodeAt(i)] = i;
+	}
+	ccToValue[",".charCodeAt(0)] = END_SEGMENT_BIT;
+	ccToValue[";".charCodeAt(0)] = NEXT_LINE;
+}
+const ccMax = ccToValue.length - 1;
+
+/**
+ * @param {string} mappings the mappings string
+ * @param {function(number, number, number, number, number, number): void} onMapping called for each mapping
+ * @returns {void}
+ */
+const readMappings = (mappings, onMapping) => {
+	// generatedColumn, [sourceIndex, originalLine, orignalColumn, [nameIndex]]
+	const currentData = new Uint32Array([0, 0, 1, 0, 0]);
+	let currentDataPos = 0;
+	// currentValue will include a sign bit at bit 0
+	let currentValue = 0;
+	let currentValuePos = 0;
+	let generatedLine = 1;
+	let generatedColumn = -1;
+	for (let i = 0; i < mappings.length; i++) {
+		const cc = mappings.charCodeAt(i);
+		if (cc > ccMax) continue;
+		const value = ccToValue[cc];
+		if ((value & END_SEGMENT_BIT) !== 0) {
+			// End current segment
+			if (currentData[0] > generatedColumn) {
+				if (currentDataPos === 1) {
+					onMapping(generatedLine, currentData[0], -1, -1, -1, -1);
+				} else if (currentDataPos === 4) {
+					onMapping(
+						generatedLine,
+						currentData[0],
+						currentData[1],
+						currentData[2],
+						currentData[3],
+						-1
+					);
+				} else if (currentDataPos === 5) {
+					onMapping(
+						generatedLine,
+						currentData[0],
+						currentData[1],
+						currentData[2],
+						currentData[3],
+						currentData[4]
+					);
+				}
+				generatedColumn = currentData[0];
+			}
+			currentDataPos = 0;
+			if (value === NEXT_LINE) {
+				// Start new line
+				generatedLine++;
+				currentData[0] = 0;
+				generatedColumn = -1;
+			}
+		} else if ((value & CONTINUATION_BIT) === 0) {
+			// last sextet
+			currentValue |= value << currentValuePos;
+			const finalValue =
+				currentValue & 1 ? -(currentValue >> 1) : currentValue >> 1;
+			currentData[currentDataPos++] += finalValue;
+			currentValuePos = 0;
+			currentValue = 0;
+		} else {
+			currentValue |= (value & DATA_MASK) << currentValuePos;
+			currentValuePos += 5;
+		}
+	}
+	// End current segment
+	if (currentDataPos === 1) {
+		onMapping(generatedLine, currentData[0], -1, -1, -1, -1);
+	} else if (currentDataPos === 4) {
+		onMapping(
+			generatedLine,
+			currentData[0],
+			currentData[1],
+			currentData[2],
+			currentData[3],
+			-1
+		);
+	} else if (currentDataPos === 5) {
+		onMapping(
+			generatedLine,
+			currentData[0],
+			currentData[1],
+			currentData[2],
+			currentData[3],
+			currentData[4]
+		);
+	}
+};
+
+module.exports = readMappings;