1 files changed, 37 insertions, 0 deletions
diff --git a/web/frontend/official-climb-profile-logic.test.ts b/web/frontend/official-climb-profile-logic.test.ts
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+++ b/web/frontend/official-climb-profile-logic.test.ts
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+import test from "node:test";
+import assert from "node:assert/strict";
+import { displayStepForLength, profileBandForSlope, officialProfileSections } from "./official-climb-profile-logic.ts";
+
+test("selects a display step that keeps long profiles readable", () => {
+  assert.equal(displayStepForLength(2_400), 100);
+  assert.equal(displayStepForLength(4_500), 200);
+  assert.equal(displayStepForLength(7_000), 500);
+  assert.equal(displayStepForLength(20_000), 1000);
+});
+
+test("assigns each slope to its color band", () => {
+  assert.equal(profileBandForSlope(-0.1), "downhill");
+  assert.equal(profileBandForSlope(2.9), "0-3");
+  assert.equal(profileBandForSlope(3), "3-6");
+  assert.equal(profileBandForSlope(6), "6-9");
+  assert.equal(profileBandForSlope(9), "9-12");
+  assert.equal(profileBandForSlope(12), "12-plus");
+});
+
+test("interpolates profile sections at the selected step", () => {
+  const points = [
+    { distanceKm: 0, elevationM: 100 },
+    { distanceKm: 0.12, elevationM: 106 },
+    { distanceKm: 0.2, elevationM: 114 },
+    { distanceKm: 0.25, elevationM: 120 },
+  ];
+  const sections = officialProfileSections(points, 0, 3, 100);
+
+  assert.equal(sections.length, 3);
+  assert.equal(sections[0].startDistanceKm, 0);
+  assert.equal(sections[0].endDistanceKm, 0.1);
+  assert.equal(sections[0].startElevation, 100);
+  assert.equal(sections[0].endElevation, 105);
+  assert.equal(sections[2].endDistanceKm, 0.25);
+  assert.equal(sections[2].endElevation, 120);
+});