fix(cli/unstable): clamp ratio (#6690)

Co-authored-by: Yoshiya Hinosawa <[email protected]>

Author: timreichen

cli/unstable_progress_bar.ts

@@ -121,6 +121,10 @@ function defaultFormatter(x: ProgressBarFormatter) {
   return `[${x.styledTime}] [${x.progressBar}] [${x.styledData()}]`;
 }
 
+function clamp(value: number, min: number, max: number) {
+  return Math.min(Math.max(value, min), max);
+}
+
 /**
  * `ProgressBar` is a customisable class that reports updates to a
  * {@link WritableStream} on a 1s interval. Progress is communicated by using
@@ -265,7 +269,8 @@ export class ProgressBar {
   #createFormatterObject() {
     const time = Date.now() - this.#startTime;
 
-    const size = this.value / this.max * this.#barLength | 0;
+    const ratio = clamp(this.value / this.max, 0, 1);
+    const size = Math.trunc(ratio * this.#barLength);
     const fillChars = this.#fillChar.repeat(size);
     const emptyChars = this.#emptyChar.repeat(this.#barLength - size);
 

cli/unstable_progress_bar_test.ts

@@ -139,3 +139,60 @@ Deno.test("ProgressBar() does not leak resources when immediately stopped", asyn
   const progressBar = new ProgressBar({ max: 10 });
   await progressBar.stop();
 });
+
+Deno.test("ProgressBar() handles value < 0", async () => {
+  using _fakeTime = new FakeTime();
+  const { readable, writable } = new TransformStream();
+  const bar = new ProgressBar({ writable, max: 2 ** 10, value: -1 });
+  bar.stop().then(() => writable.close());
+
+  const expected = [
+    "\r\x1b[K[00:00] [--------------------------------------------------] [-0.00/1.00 KiB]",
+    "\r\x1b[K[00:00] [--------------------------------------------------] [-0.00/1.00 KiB]",
+    "\n",
+  ];
+
+  const actual: string[] = [];
+  for await (const buffer of readable) {
+    actual.push(decoder.decode(buffer));
+  }
+  assertEquals(actual, expected);
+});
+
+Deno.test("ProgressBar() handles max < 0", async () => {
+  using _fakeTime = new FakeTime();
+  const { readable, writable } = new TransformStream();
+  const bar = new ProgressBar({ writable, max: -1 });
+  bar.stop().then(() => writable.close());
+
+  const expected = [
+    "\r\x1b[K[00:00] [--------------------------------------------------] [0.00/-0.00 KiB]",
+    "\r\x1b[K[00:00] [--------------------------------------------------] [0.00/-0.00 KiB]",
+    "\n",
+  ];
+
+  const actual: string[] = [];
+  for await (const buffer of readable) {
+    actual.push(decoder.decode(buffer));
+  }
+  assertEquals(actual, expected);
+});
+
+Deno.test("ProgressBar() handles value > max", async () => {
+  using _fakeTime = new FakeTime();
+  const { readable, writable } = new TransformStream();
+  const bar = new ProgressBar({ writable, max: 2 ** 10, value: 2 ** 10 + 1 });
+  bar.stop().then(() => writable.close());
+
+  const expected = [
+    "\r\x1b[K[00:00] [##################################################] [1.00/1.00 KiB]",
+    "\r\x1b[K[00:00] [##################################################] [1.00/1.00 KiB]",
+    "\n",
+  ];
+
+  const actual: string[] = [];
+  for await (const buffer of readable) {
+    actual.push(decoder.decode(buffer));
+  }
+  assertEquals(actual, expected);
+});