Re-write of search addon (squashed)

Author: AnouarTouati

addons/addon-search/src/BufferToStringDataTransformers.ts

@@ -0,0 +1,99 @@
+import { Terminal } from '@xterm/xterm';
+export type LineCacheEntry = [
+  /**
+   * The string representation of a line (as opposed to the buffer cell representation).
+   */
+  lineAsString: string,
+  /**
+   * The offsets where each line starts when the entry describes a wrapped line.
+   */
+  lineOffsets: number[]
+];
+export function stringLengthToBufferSize(terminal: Terminal,row: number, offset: number): number {
+  const line = terminal!.buffer.active.getLine(row);
+  if (!line) {
+    return 0;
+  }
+  for (let i = 0; i < offset; i++) {
+    const cell = line.getCell(i);
+    if (!cell) {
+      break;
+    }
+    // Adjust the searchIndex to normalize emoji into single chars
+    const char = cell.getChars();
+    if (char.length > 1) {
+      offset -= char.length - 1;
+    }
+    // Adjust the searchIndex for empty characters following wide unicode
+    // chars (eg. CJK)
+    const nextCell = line.getCell(i + 1);
+    if (nextCell && nextCell.getWidth() === 0) {
+      offset++;
+    }
+  }
+  return offset;
+}
+
+
+export function bufferColsToStringOffset(terminal: Terminal,startRow: number, cols: number): number {
+  let lineIndex = startRow;
+  let offset = 0;
+  let line = terminal.buffer.active.getLine(lineIndex);
+  while (cols > 0 && line) {
+    for (let i = 0; i < cols && i < terminal.cols; i++) {
+      const cell = line.getCell(i);
+      if (!cell) {
+        break;
+      }
+      if (cell.getWidth()) {
+        // Treat null characters as whitespace to align with the translateToString API
+        offset += cell.getCode() === 0 ? 1 : cell.getChars().length;
+      }
+    }
+    lineIndex++;
+    line = terminal.buffer.active.getLine(lineIndex);
+    if (line && !line.isWrapped) {
+      break;
+    }
+    cols -= terminal.cols;
+  }
+  return offset;
+}
+
+
+/**
+ * Translates a buffer line to a string, including subsequent lines if they are wraps.
+ * Wide characters will count as two columns in the resulting string. This
+ * function is useful for getting the actual text underneath the raw selection
+ * position.
+ * @param lineIndex The index of the line being translated.
+ * @param trimRight Whether to trim whitespace to the right.
+ */
+export function translateBufferLineToStringWithWrap(terminal: Terminal,lineIndex: number, trimRight: boolean): LineCacheEntry {
+  const strings = [];
+  const lineOffsets = [0];
+  let line = terminal.buffer.active.getLine(lineIndex);
+  while (line) {
+    const nextLine = terminal.buffer.active.getLine(lineIndex + 1);
+    const lineWrapsToNext = nextLine ? nextLine.isWrapped : false;
+    let string = line.translateToString(!lineWrapsToNext && trimRight);
+    if (lineWrapsToNext && nextLine) {
+      const lastCell = line.getCell(line.length - 1);
+      const lastCellIsNull = lastCell && lastCell.getCode() === 0 && lastCell.getWidth() === 1;
+      // a wide character wrapped to the next line
+      if (lastCellIsNull && nextLine.getCell(0)?.getWidth() === 2) {
+        string = string.slice(0, -1);
+      }
+    }
+    strings.push(string);
+    if (lineWrapsToNext) {
+      lineOffsets.push(lineOffsets[lineOffsets.length - 1] + string.length);
+    } else {
+      break;
+    }
+    lineIndex++;
+    line = nextLine;
+  }
+  return [strings.join(''), lineOffsets];
+}
+