fix(terminal): 修正宽字符拖选边界

package.json

@@ -36,7 +36,7 @@
     "fmt:rust:check": "cargo fmt --manifest-path src-tauri/Cargo.toml -- --check",
     "i18n:check": "prettier --check src/i18n/locales/*.json",
     "i18n:fix": "prettier --write src/i18n/locales/*.json",
-    "postinstall": "node scripts/patch-xterm-webgl-clear-model.cjs"
+    "postinstall": "node scripts/patch-xterm-webgl-clear-model.cjs && node scripts/patch-xterm-wide-char-selection.cjs"
   },
   "dependencies": {
     "@codemirror/autocomplete": "^6.20.3",

scripts/patch-xterm-wide-char-selection.cjs

@@ -0,0 +1,214 @@
+#!/usr/bin/env node
+/* global process, console */
+/**
+ * Fix @xterm/xterm drag-selection boundaries for width-2 characters.
+ *
+ * xterm's selection coordinates use a half-cell offset. When that lands on the
+ * continuation cell of a width-2 character, SelectionService currently always
+ * advances to the character's right boundary. This makes the effective boundary
+ * occur around one quarter of the rendered glyph instead of at its visual center.
+ *
+ * Fix: only for normal mouse selection, use the same relative pointer coordinate
+ * helper and rendered cell width that xterm already uses. A continuation-cell hit
+ * snaps left before the wide character on its visual left half and right after it
+ * on its visual right half. Other selection modes retain xterm's existing logic.
+ *
+ * This script is intended for:
+ *   @xterm/xterm@6.1.0-beta.288
+ *
+ * It is idempotent and fails fast when the installed package or minified bundle
+ * no longer matches the expected version, so dependency upgrades cannot silently
+ * reintroduce the issue.
+ */
+
+"use strict";
+
+const fs = require("node:fs");
+const path = require("node:path");
+
+const PACKAGE_NAME = "@xterm/xterm";
+const EXPECTED_VERSION = "6.1.0-beta.288";
+const MARKER = "/*nyaterm:wide-char-selection-midpoint*/";
+const STATE = "_nyatermWideCharMidpointSelection";
+
+const PACKAGE_DIR = path.resolve(
+  process.cwd(),
+  "node_modules",
+  "@xterm",
+  "xterm",
+);
+const PACKAGE_JSON = path.join(PACKAGE_DIR, "package.json");
+
+const TARGETS = [
+  {
+    file: path.join(PACKAGE_DIR, "lib", "xterm.mjs"),
+    // @xterm/xterm@6.1.0-beta.288 ESM bundle
+    replacements: [
+      {
+        label: "normal selection drag state",
+        original:
+          "e.preventDefault(),this._dragScrollAmount=0,this._enabled&&e.shiftKey?this._handleIncrementalClick(e)",
+        patched: `e.preventDefault(),this._dragScrollAmount=0,${MARKER}this.${STATE}=this._enabled&&!e.shiftKey&&!e.altKey&&!e.ctrlKey&&!e.metaKey&&e.detail===1,this._enabled&&e.shiftKey?this._handleIncrementalClick(e)`,
+      },
+      {
+        label: "normal selection start",
+        original:
+          "r&&r.length!==this._model.selectionStart[0]&&r.hasWidth(this._model.selectionStart[0])===0&&this._model.selectionStart[0]++",
+        patched: `r&&r.length!==this._model.selectionStart[0]&&r.hasWidth(this._model.selectionStart[0])===0&&(this.${STATE}?this._model.selectionStart[0]+=qt(this._coreBrowserService.window,e,this._screenElement)[0]<=this._model.selectionStart[0]*this._renderService.dimensions.css.cell.width?-1:1:this._model.selectionStart[0]++)`,
+      },
+      {
+        label: "normal selection end",
+        original:
+          "s&&s.hasWidth(this._model.selectionEnd[0])===0&&this._model.selectionEnd[0]<this._bufferService.cols&&this._model.selectionEnd[0]++",
+        patched: `s&&s.hasWidth(this._model.selectionEnd[0])===0&&this._model.selectionEnd[0]<this._bufferService.cols&&(this.${STATE}?this._model.selectionEnd[0]+=qt(this._coreBrowserService.window,e,this._screenElement)[0]<=this._model.selectionEnd[0]*this._renderService.dimensions.css.cell.width?-1:1:this._model.selectionEnd[0]++)`,
+      },
+    ],
+  },
+  {
+    file: path.join(PACKAGE_DIR, "lib", "xterm.js"),
+    // @xterm/xterm@6.1.0-beta.288 CJS bundle
+    replacements: [
+      {
+        label: "normal selection drag state",
+        original:
+          "e.preventDefault(),this._dragScrollAmount=0,this._enabled&&e.shiftKey?this._handleIncrementalClick(e)",
+        patched: `e.preventDefault(),this._dragScrollAmount=0,${MARKER}this.${STATE}=this._enabled&&!e.shiftKey&&!e.altKey&&!e.ctrlKey&&!e.metaKey&&1===e.detail,this._enabled&&e.shiftKey?this._handleIncrementalClick(e)`,
+      },
+      {
+        label: "normal selection start",
+        original:
+          "i&&i.length!==this._model.selectionStart[0]&&0===i.hasWidth(this._model.selectionStart[0])&&this._model.selectionStart[0]++",
+        patched: `i&&i.length!==this._model.selectionStart[0]&&0===i.hasWidth(this._model.selectionStart[0])&&(this.${STATE}?this._model.selectionStart[0]+=(0,l.getCoordsRelativeToElement)(this._coreBrowserService.window,e,this._screenElement)[0]<=this._model.selectionStart[0]*this._renderService.dimensions.css.cell.width?-1:1:this._model.selectionStart[0]++)`,
+      },
+      {
+        label: "normal selection end",
+        original:
+          "const i=this._bufferService.buffer;if(this._model.selectionEnd[1]<i.lines.length){const e=i.lines.get(this._model.selectionEnd[1]);e&&0===e.hasWidth(this._model.selectionEnd[0])&&this._model.selectionEnd[0]<this._bufferService.cols&&this._model.selectionEnd[0]++}",
+        patched: `const i=this._bufferService.buffer;if(this._model.selectionEnd[1]<i.lines.length){const s=i.lines.get(this._model.selectionEnd[1]);s&&0===s.hasWidth(this._model.selectionEnd[0])&&this._model.selectionEnd[0]<this._bufferService.cols&&(this.${STATE}?this._model.selectionEnd[0]+=(0,l.getCoordsRelativeToElement)(this._coreBrowserService.window,e,this._screenElement)[0]<=this._model.selectionEnd[0]*this._renderService.dimensions.css.cell.width?-1:1:this._model.selectionEnd[0]++)}`,
+      },
+    ],
+  },
+];
+
+function fail(message) {
+  throw new Error(`[patch-xterm-wide-char-selection] ${message}`);
+}
+
+function countOccurrences(source, needle) {
+  return source.split(needle).length - 1;
+}
+
+function writeFileAtomically(filename, content) {
+  const temporary = `${filename}.nyaterm-patch-${process.pid}.tmp`;
+  fs.writeFileSync(temporary, content, "utf8");
+  fs.renameSync(temporary, filename);
+}
+
+function verifyPatchedSource(source, relative, replacements) {
+  const markerCount = countOccurrences(source, MARKER);
+  if (markerCount !== 1) {
+    fail(
+      `expected exactly one patch marker in ${relative}, found ${markerCount}`,
+    );
+  }
+
+  for (const replacement of replacements) {
+    const originalCount = countOccurrences(source, replacement.original);
+    const patchedCount = countOccurrences(source, replacement.patched);
+    if (originalCount !== 0 || patchedCount !== 1) {
+      fail(
+        `patch verification failed for ${replacement.label} in ${relative}: ` +
+          `original=${originalCount} patched=${patchedCount}`,
+      );
+    }
+  }
+}
+
+if (!fs.existsSync(PACKAGE_JSON)) {
+  fail(`${PACKAGE_NAME} is not installed: ${PACKAGE_JSON}`);
+}
+
+let packageJson;
+try {
+  packageJson = JSON.parse(fs.readFileSync(PACKAGE_JSON, "utf8"));
+} catch (error) {
+  fail(
+    `cannot read ${PACKAGE_JSON}: ${
+      error instanceof Error ? error.message : String(error)
+    }`,
+  );
+}
+
+if (packageJson.version !== EXPECTED_VERSION) {
+  fail(
+    `unsupported ${PACKAGE_NAME} version ${JSON.stringify(packageJson.version)}; ` +
+      `expected ${EXPECTED_VERSION}. Review and refresh this patch before upgrading.`,
+  );
+}
+
+let patched = 0;
+let already = 0;
+
+for (const { file, replacements } of TARGETS) {
+  const relative = path.relative(process.cwd(), file);
+
+  if (!fs.existsSync(file)) {
+    fail(`runtime bundle not found: ${relative}`);
+  }
+
+  let source;
+  try {
+    source = fs.readFileSync(file, "utf8");
+  } catch (error) {
+    fail(
+      `cannot read ${relative}: ${
+        error instanceof Error ? error.message : String(error)
+      }`,
+    );
+  }
+
+  if (source.includes(MARKER)) {
+    verifyPatchedSource(source, relative, replacements);
+    already += 1;
+    continue;
+  }
+
+  for (const replacement of replacements) {
+    const occurrences = countOccurrences(source, replacement.original);
+    if (occurrences !== 1) {
+      fail(
+        `expected exactly one ${replacement.label} fragment in ${relative}, ` +
+          `found ${occurrences}. The minified xterm bundle may have changed.`,
+      );
+    }
+    if (source.includes(replacement.patched)) {
+      fail(`unexpected partial patch for ${replacement.label} in ${relative}`);
+    }
+  }
+
+  let patchedSource = source;
+  for (const replacement of replacements) {
+    patchedSource = patchedSource.replace(
+      replacement.original,
+      replacement.patched,
+    );
+  }
+  verifyPatchedSource(patchedSource, relative, replacements);
+
+  try {
+    writeFileAtomically(file, patchedSource);
+  } catch (error) {
+    fail(
+      `cannot write ${relative}: ${
+        error instanceof Error ? error.message : String(error)
+      }`,
+    );
+  }
+
+  patched += 1;
+}
+
+console.log(
+  `[patch-xterm-wide-char-selection] midpoint snapping: ` +
+    `patched=${patched} already=${already} total=${TARGETS.length}`,
+);

src/test/xtermWideCharSelectionPatch.test.ts

@@ -0,0 +1,62 @@
+import fs from "node:fs";
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+
+const packageDir = path.resolve(
+  process.cwd(),
+  "node_modules",
+  "@xterm",
+  "xterm",
+  "lib",
+);
+
+const cases = [
+  {
+    name: "ESM",
+    file: "xterm.mjs",
+    state:
+      "this._nyatermWideCharMidpointSelection=this._enabled&&!e.shiftKey&&!e.altKey&&!e.ctrlKey&&!e.metaKey&&e.detail===1",
+    startFallback: ":this._model.selectionStart[0]++)",
+    endFallback: ":this._model.selectionEnd[0]++)",
+  },
+  {
+    name: "CJS",
+    file: "xterm.js",
+    state:
+      "this._nyatermWideCharMidpointSelection=this._enabled&&!e.shiftKey&&!e.altKey&&!e.ctrlKey&&!e.metaKey&&1===e.detail",
+    startFallback: ":this._model.selectionStart[0]++)",
+    endFallback: ":this._model.selectionEnd[0]++)",
+  },
+] as const;
+
+describe("xterm wide-character selection patch", () => {
+  it.each(cases)(
+    "$name keeps Shift/modified selection on xterm's original wide-cell behavior",
+    ({ file, state, startFallback, endFallback }) => {
+      const source = fs.readFileSync(path.join(packageDir, file), "utf8");
+      const stateName = "_nyatermWideCharMidpointSelection";
+
+      expect(source).toContain("/*nyaterm:wide-char-selection-midpoint*/");
+      expect(source).toContain(state);
+      expect(source.split(stateName)).toHaveLength(4);
+
+      const startUse = source.indexOf(
+        `this.${stateName}?this._model.selectionStart[0]+=`,
+      );
+      const endUse = source.indexOf(
+        `this.${stateName}?this._model.selectionEnd[0]+=`,
+      );
+      expect(startUse).toBeGreaterThan(-1);
+      expect(endUse).toBeGreaterThan(startUse);
+      expect(source.slice(startUse, startUse + 500)).toContain(startFallback);
+      expect(source.slice(endUse, endUse + 500)).toContain(endFallback);
+
+      // The decision is captured once on mousedown. Mousemove must not switch
+      // algorithms based on the modifier state of later events.
+      expect(source).not.toContain("_activeSelectionMode===0&&!e.shiftKey?");
+      expect(source).not.toContain(
+        "0===this._activeSelectionMode&&!e.shiftKey?",
+      );
+    },
+  );
+});