Move BufferReflow to core

2019-05-17 23:37:44 -07:00
parent 610c4c9726
commit 88c1ff6f11
3 changed files with 36 additions and 36 deletions
@@ -0,0 +1,92 @@
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+import { assert } from 'chai';
+import { BufferLine, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE } from './BufferLine';
+import { reflowSmallerGetNewLineLengths } from './BufferReflow';
+
+describe('BufferReflow', () => {
+  describe('reflowSmallerGetNewLineLengths', () => {
+    it('should return correct line lengths for a small line with wide characters', () => {
+      const line = new BufferLine(4);
+      line.set(0, [0, '汉', 2, '汉'.charCodeAt(0)]);
+      line.set(1, [0, '', 0, 0]);
+      line.set(2, [0, '语', 2, '语'.charCodeAt(0)]);
+      line.set(3, [0, '', 0, 0]);
+      assert.equal(line.translateToString(true), '汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 4, 3), [2, 2], 'line: 汉, 语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 4, 2), [2, 2], 'line: 汉, 语');
+    });
+    it('should return correct line lengths for a large line with wide characters', () => {
+      const line = new BufferLine(12);
+      for (let i = 0; i < 12; i += 4) {
+        line.set(i, [0, '汉', 2, '汉'.charCodeAt(0)]);
+        line.set(i + 2, [0, '语', 2, '语'.charCodeAt(0)]);
+      }
+      for (let i = 1; i < 12; i += 2) {
+        line.set(i, [0, '', 0, 0]);
+        line.set(i, [0, '', 0, 0]);
+      }
+      assert.equal(line.translateToString(), '汉语汉语汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 11), [10, 2], 'line: 汉语汉语汉, 语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 10), [10, 2], 'line: 汉语汉语汉, 语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 9), [8, 4], 'line: 汉语汉语, 汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 8), [8, 4], 'line: 汉语汉语, 汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 7), [6, 6], 'line: 汉语汉, 语汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 6), [6, 6], 'line: 汉语汉, 语汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 5), [4, 4, 4], 'line: 汉语, 汉语, 汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 4), [4, 4, 4], 'line: 汉语, 汉语, 汉语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 3), [2, 2, 2, 2, 2, 2], 'line: 汉, 语, 汉, 语, 汉, 语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 12, 2), [2, 2, 2, 2, 2, 2], 'line: 汉, 语, 汉, 语, 汉, 语');
+    });
+    it('should return correct line lengths for a string with wide and single characters', () => {
+      const line = new BufferLine(6);
+      line.set(0, [0, 'a', 1, 'a'.charCodeAt(0)]);
+      line.set(1, [0, '汉', 2, '汉'.charCodeAt(0)]);
+      line.set(2, [0, '', 0, 0]);
+      line.set(3, [0, '语', 2, '语'.charCodeAt(0)]);
+      line.set(4, [0, '', 0, 0]);
+      line.set(5, [0, 'b', 1, 'b'.charCodeAt(0)]);
+      assert.equal(line.translateToString(), 'a汉语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 6, 5), [5, 1], 'line: a汉语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 6, 4), [3, 3], 'line: a汉, 语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 6, 3), [3, 3], 'line: a汉, 语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 6, 2), [1, 2, 2, 1], 'line: a, 汉, 语, b');
+    });
+    it('should return correct line lengths for a wrapped line with wide and single characters', () => {
+      const line1 = new BufferLine(6);
+      line1.set(0, [0, 'a', 1, 'a'.charCodeAt(0)]);
+      line1.set(1, [0, '汉', 2, '汉'.charCodeAt(0)]);
+      line1.set(2, [0, '', 0, 0]);
+      line1.set(3, [0, '语', 2, '语'.charCodeAt(0)]);
+      line1.set(4, [0, '', 0, 0]);
+      line1.set(5, [0, 'b', 1, 'b'.charCodeAt(0)]);
+      const line2 = new BufferLine(6, undefined, true);
+      line2.set(0, [0, 'a', 1, 'a'.charCodeAt(0)]);
+      line2.set(1, [0, '汉', 2, '汉'.charCodeAt(0)]);
+      line2.set(2, [0, '', 0, 0]);
+      line2.set(3, [0, '语', 2, '语'.charCodeAt(0)]);
+      line2.set(4, [0, '', 0, 0]);
+      line2.set(5, [0, 'b', 1, 'b'.charCodeAt(0)]);
+      assert.equal(line1.translateToString(), 'a汉语b');
+      assert.equal(line2.translateToString(), 'a汉语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line1, line2], 6, 5), [5, 4, 3], 'lines: a汉语, ba汉, 语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line1, line2], 6, 4), [3, 4, 4, 1], 'lines: a汉, 语ba, 汉语, b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line1, line2], 6, 3), [3, 3, 3, 3], 'lines: a汉, 语b, a汉, 语b');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line1, line2], 6, 2), [1, 2, 2, 2, 2, 2, 1], 'lines: a, 汉, 语, ba, 汉, 语, b');
+    });
+    it('should work on lines ending in null space', () => {
+      const line = new BufferLine(5);
+      line.set(0, [0, '汉', 2, '汉'.charCodeAt(0)]);
+      line.set(1, [0, '', 0, 0]);
+      line.set(2, [0, '语', 2, '语'.charCodeAt(0)]);
+      line.set(3, [0, '', 0, 0]);
+      line.set(4, [0, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]);
+      assert.equal(line.translateToString(true), '汉语');
+      assert.equal(line.translateToString(false), '汉语 ');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 4, 3), [2, 2], 'line: 汉, 语');
+      assert.deepEqual(reflowSmallerGetNewLineLengths([line], 4, 2), [2, 2], 'line: 汉, 语');
+    });
+  });
+});
@@ -0,0 +1,220 @@
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { BufferLine } from './BufferLine';
+import { CircularList } from '../../common/CircularList';
+import { IBufferLine, ICellData } from '../Types';
+
+export interface INewLayoutResult {
+  layout: number[];
+  countRemoved: number;
+}
+
+/**
+ * Evaluates and returns indexes to be removed after a reflow larger occurs. Lines will be removed
+ * when a wrapped line unwraps.
+ * @param lines The buffer lines.
+ * @param newCols The columns after resize.
+ */
+export function reflowLargerGetLinesToRemove(lines: CircularList<IBufferLine>, oldCols: number, newCols: number, bufferAbsoluteY: number, nullCell: ICellData): number[] {
+  // Gather all BufferLines that need to be removed from the Buffer here so that they can be
+  // batched up and only committed once
+  const toRemove: number[] = [];
+
+  for (let y = 0; y < lines.length - 1; y++) {
+    // Check if this row is wrapped
+    let i = y;
+    let nextLine = lines.get(++i) as BufferLine;
+    if (!nextLine.isWrapped) {
+      continue;
+    }
+
+    // Check how many lines it's wrapped for
+    const wrappedLines: BufferLine[] = [lines.get(y) as BufferLine];
+    while (i < lines.length && nextLine.isWrapped) {
+      wrappedLines.push(nextLine);
+      nextLine = lines.get(++i) as BufferLine;
+    }
+
+    // If these lines contain the cursor don't touch them, the program will handle fixing up wrapped
+    // lines with the cursor
+    if (bufferAbsoluteY >= y && bufferAbsoluteY < i) {
+      y += wrappedLines.length - 1;
+      continue;
+    }
+
+    // Copy buffer data to new locations
+    let destLineIndex = 0;
+    let destCol = getWrappedLineTrimmedLength(wrappedLines, destLineIndex, oldCols);
+    let srcLineIndex = 1;
+    let srcCol = 0;
+    while (srcLineIndex < wrappedLines.length) {
+      const srcTrimmedTineLength = getWrappedLineTrimmedLength(wrappedLines, srcLineIndex, oldCols);
+      const srcRemainingCells = srcTrimmedTineLength - srcCol;
+      const destRemainingCells = newCols - destCol;
+      const cellsToCopy = Math.min(srcRemainingCells, destRemainingCells);
+
+      wrappedLines[destLineIndex].copyCellsFrom(wrappedLines[srcLineIndex], srcCol, destCol, cellsToCopy, false);
+
+      destCol += cellsToCopy;
+      if (destCol === newCols) {
+        destLineIndex++;
+        destCol = 0;
+      }
+      srcCol += cellsToCopy;
+      if (srcCol === srcTrimmedTineLength) {
+        srcLineIndex++;
+        srcCol = 0;
+      }
+
+      // Make sure the last cell isn't wide, if it is copy it to the current dest
+      if (destCol === 0 && destLineIndex !== 0) {
+        if (wrappedLines[destLineIndex - 1].getWidth(newCols - 1) === 2) {
+          wrappedLines[destLineIndex].copyCellsFrom(wrappedLines[destLineIndex - 1], newCols - 1, destCol++, 1, false);
+          // Null out the end of the last row
+          wrappedLines[destLineIndex - 1].setCell(newCols - 1, nullCell);
+        }
+      }
+    }
+
+    // Clear out remaining cells or fragments could remain;
+    wrappedLines[destLineIndex].replaceCells(destCol, newCols, nullCell);
+
+    // Work backwards and remove any rows at the end that only contain null cells
+    let countToRemove = 0;
+    for (let i = wrappedLines.length - 1; i > 0; i--) {
+      if (i > destLineIndex || wrappedLines[i].getTrimmedLength() === 0) {
+        countToRemove++;
+      } else {
+        break;
+      }
+    }
+
+    if (countToRemove > 0) {
+      toRemove.push(y + wrappedLines.length - countToRemove); // index
+      toRemove.push(countToRemove);
+    }
+
+    y += wrappedLines.length - 1;
+  }
+  return toRemove;
+}
+
+/**
+ * Creates and return the new layout for lines given an array of indexes to be removed.
+ * @param lines The buffer lines.
+ * @param toRemove The indexes to remove.
+ */
+export function reflowLargerCreateNewLayout(lines: CircularList<IBufferLine>, toRemove: number[]): INewLayoutResult {
+  const layout: number[] = [];
+  // First iterate through the list and get the actual indexes to use for rows
+  let nextToRemoveIndex = 0;
+  let nextToRemoveStart = toRemove[nextToRemoveIndex];
+  let countRemovedSoFar = 0;
+  for (let i = 0; i < lines.length; i++) {
+    if (nextToRemoveStart === i) {
+      const countToRemove = toRemove[++nextToRemoveIndex];
+
+      // Tell markers that there was a deletion
+      lines.onDeleteEmitter.fire({
+        index: i - countRemovedSoFar,
+        amount: countToRemove
+      });
+
+      i += countToRemove - 1;
+      countRemovedSoFar += countToRemove;
+      nextToRemoveStart = toRemove[++nextToRemoveIndex];
+    } else {
+      layout.push(i);
+    }
+  }
+  return {
+    layout,
+    countRemoved: countRemovedSoFar
+  };
+}
+
+/**
+ * Applies a new layout to the buffer. This essentially does the same as many splice calls but it's
+ * done all at once in a single iteration through the list since splice is very expensive.
+ * @param lines The buffer lines.
+ * @param newLayout The new layout to apply.
+ */
+export function reflowLargerApplyNewLayout(lines: CircularList<IBufferLine>, newLayout: number[]): void {
+  // Record original lines so they don't get overridden when we rearrange the list
+  const newLayoutLines: BufferLine[] = [];
+  for (let i = 0; i < newLayout.length; i++) {
+    newLayoutLines.push(lines.get(newLayout[i]) as BufferLine);
+  }
+
+  // Rearrange the list
+  for (let i = 0; i < newLayoutLines.length; i++) {
+    lines.set(i, newLayoutLines[i]);
+  }
+  lines.length = newLayout.length;
+}
+
+/**
+ * Gets the new line lengths for a given wrapped line. The purpose of this function it to pre-
+ * compute the wrapping points since wide characters may need to be wrapped onto the following line.
+ * This function will return an array of numbers of where each line wraps to, the resulting array
+ * will only contain the values `newCols` (when the line does not end with a wide character) and
+ * `newCols - 1` (when the line does end with a wide character), except for the last value which
+ * will contain the remaining items to fill the line.
+ *
+ * Calling this with a `newCols` value of `1` will lock up.
+ *
+ * @param wrappedLines The wrapped lines to evaluate.
+ * @param oldCols The columns before resize.
+ * @param newCols The columns after resize.
+ */
+export function reflowSmallerGetNewLineLengths(wrappedLines: BufferLine[], oldCols: number, newCols: number): number[] {
+  const newLineLengths: number[] = [];
+  const cellsNeeded = wrappedLines.map((l, i) => getWrappedLineTrimmedLength(wrappedLines, i, oldCols)).reduce((p, c) => p + c);
+
+  // Use srcCol and srcLine to find the new wrapping point, use that to get the cellsAvailable and
+  // linesNeeded
+  let srcCol = 0;
+  let srcLine = 0;
+  let cellsAvailable = 0;
+  while (cellsAvailable < cellsNeeded) {
+    if (cellsNeeded - cellsAvailable < newCols) {
+      // Add the final line and exit the loop
+      newLineLengths.push(cellsNeeded - cellsAvailable);
+      break;
+    }
+    srcCol += newCols;
+    const oldTrimmedLength = getWrappedLineTrimmedLength(wrappedLines, srcLine, oldCols);
+    if (srcCol > oldTrimmedLength) {
+      srcCol -= oldTrimmedLength;
+      srcLine++;
+    }
+    const endsWithWide = wrappedLines[srcLine].getWidth(srcCol - 1) === 2;
+    if (endsWithWide) {
+      srcCol--;
+    }
+    const lineLength = endsWithWide ? newCols - 1 : newCols;
+    newLineLengths.push(lineLength);
+    cellsAvailable += lineLength;
+  }
+
+  return newLineLengths;
+}
+
+export function getWrappedLineTrimmedLength(lines: BufferLine[], i: number, cols: number): number {
+  // If this is the last row in the wrapped line, get the actual trimmed length
+  if (i === lines.length - 1) {
+    return lines[i].getTrimmedLength();
+  }
+  // Detect whether the following line starts with a wide character and the end of the current line
+  // is null, if so then we can be pretty sure the null character should be excluded from the line
+  // length]
+  const endsInNull = !(lines[i].hasContent(cols - 1)) && lines[i].getWidth(cols - 1) === 1;
+  const followingLineStartsWithWide = lines[i + 1].getWidth(0) === 2;
+  if (endsInNull && followingLineStartsWithWide) {
+    return cols - 1;
+  }
+  return cols;
+}