Speed up cold diffs and wrapped text measurement (#4676)

* perf(app): optimize wrapped measurements and checkpoint native layout experiment Compute full grapheme geometry only for final wrap fragments. Preserve shaped-text search behavior while bounding additive wrap probes. Keep the Android background layout experiment isolated from the normal diff renderer; native renderer integration and iOS bindings remain unfinished. * perf(server): reduce cold diff generation work Keep active diff reads owned across invalidation and wait for the initial watcher inventory before cold generation. Batch patch and blob reads while preserving per-file size isolation, bounded output, and daemon responsiveness. Avoid constructing fallback tokens when full-file highlighting already covers both sides. * test(server): exercise oversized highlighted diff rejection The single-line fixture now bypasses highlighting under the long-line guard, so it no longer reaches the structured payload limit. Use short dense lines to keep testing oversized rejection and continued socket usability. * fix(server): queue fresh diffs for forced reads A forced request following a repository mutation must not reuse an older active build. Invalidate that result and coalesce waiting callers onto one subsequent build. Give the cache a named object input and completed-value type. * test(server): share deferred diff loader setup * test(server): name completed diff cache setup * refactor(server): use aliases for new diff imports * fix(server): keep shipped diff imports resolvable by Node The TypeScript build preserves path aliases without a runtime resolver. Restore relative imports for shipped code and declarations, and correct the server import guideline that prompted the regression.
2026-10-26 03:03:04 +00:00 · 2026-09-11 08:07:01 +02:00
parent 16d932651c
commit 33a52d0ae7
32 changed files with 1409 additions and 186 deletions
@@ -71,6 +71,78 @@ function input(overrides: Partial<BuildDiffDocumentModelInput> = {}): BuildDiffD
 }

 describe("diff document model", () => {
+  it("preserves shaped wrap breaks when joining makes a longer prefix narrower", () => {
+    const measure = (text: string) => {
+      if (text === "لا") return 30;
+      if (text === "لام") return 15;
+      return text.length * 10;
+    };
+    const fragments = measureFragments({
+      text: "لام",
+      availableWidth: 20,
+      wrapLines: true,
+      lineHeight: 18,
+      measureText: { measure, measureWidth: (graphemes) => measure(graphemes.join("")) },
+    });
+    expect(fragments.map((fragment) => fragment.text)).toEqual(["ل", "ام"]);
+    expect(fragments.map((fragment) => fragment.width)).toEqual([10, 20]);
+  });
+
+  it("does not search wrap boundaries when the remaining text already fits", () => {
+    let widthQueries = 0;
+    const fragments = measureFragments({
+      text: "const answer = value + 1;",
+      availableWidth: 300,
+      wrapLines: true,
+      lineHeight: 18,
+      measureText: {
+        measure: measurer.measure,
+        measureWidth(graphemes) {
+          widthQueries++;
+          return graphemes.length * 10;
+        },
+      },
+    });
+    expect(fragments).toHaveLength(1);
+    expect(fragments[0]?.width).toBe(250);
+    expect(widthQueries).toBe(1);
+  });
+
+  it("builds character geometry only for displayed wrapped fragments", () => {
+    let advancedGraphemes = 0;
+    const measureWidth = (graphemes: readonly string[]) => graphemes.length * 10;
+    const measureText = {
+      // Whole-string widths need not match the chunked advance contract.
+      measure: () => 999,
+      measureWidth,
+      measureAdvances(graphemes: readonly string[]) {
+        advancedGraphemes += graphemes.length;
+        return graphemes.map((_, index) => (index + 1) * 10);
+      },
+    };
+    const text = "const next = (value) => value + 1;".repeat(4);
+    const fragments = measureFragments({
+      text,
+      availableWidth: 80,
+      wrapLines: true,
+      lineHeight: 18,
+      measureText,
+    });
+
+    expect(fragments.map((fragment) => fragment.text).join("")).toBe(text);
+    expect(fragments.every((fragment) => fragment.width <= 80)).toBe(true);
+    expect(fragments).toEqual(
+      measureFragments({
+        text,
+        availableWidth: 80,
+        wrapLines: true,
+        lineHeight: 18,
+        measureText: { measure: measurer.measure },
+      }),
+    );
+    expect(advancedGraphemes).toBe(text.length);
+  });
+
  it("materializes only visible rows of a large file while preserving full horizontal extent", () => {
    const source = file("large.ts");
    source.hunks[0]!.lines = Array.from({ length: 1000 }, (_, index) => ({