From 21e19a90f4a3b3989a1485614e381976d93281c1 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 17 Jul 2024 21:23:29 +0530
Subject: [PATCH] Add test for multiple function handling

---
 kitty/animation.c      | 13 ++++++++-----
 kitty_tests/options.py |  6 ++++--
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/kitty/animation.c b/kitty/animation.c
index f90775b80..303534954 100644
--- a/kitty/animation.c
+++ b/kitty/animation.c
@@ -179,7 +179,7 @@ apply_easing_curve(const Animation *a, double val, monotonic_t duration) {
     if (!a->count) return val;
     size_t idx = MIN((size_t)(val * a->count), a->count - 1);
     animation_function *f = a->functions + idx;
-    double interval_size = 1. / a->count, interval_start = val - idx * interval_size;
+    double interval_size = 1. / a->count, interval_start = idx * interval_size;
     val = (val - interval_start) / interval_size;
     double ans = f->curve(&f->params, val, duration);
     return f->y_at_start + unit_value(ans) * f->y_size;
@@ -282,11 +282,14 @@ test_cursor_blink_easing_function(PyObject *self UNUSED, PyObject *args) {
         PyErr_SetString(PyExc_RuntimeError, "must set a cursor blink animation on the global options object first");
         return NULL;
     }
-    double t, duration_s = 0.5;
-    if (!PyArg_ParseTuple(args, "d|d", &t, &duration_s)) return NULL;
+    double t, duration_s = 0.5; int only_single = 1;
+    if (!PyArg_ParseTuple(args, "d|pd", &t, &only_single, &duration_s)) return NULL;
     monotonic_t duration = s_double_to_monotonic_t(duration_s);
-    animation_function f = a->functions[0];
-    return PyFloat_FromDouble(f.curve(f.params, t, duration));
+    if (only_single) {
+        animation_function f = a->functions[0];
+        return PyFloat_FromDouble(f.curve(f.params, t, duration));
+    }
+    return PyFloat_FromDouble(apply_easing_curve(a, t, duration));
 }
 
 static PyMethodDef module_methods[] = {
diff --git a/kitty_tests/options.py b/kitty_tests/options.py
index 43a5bd206..2193515a0 100644
--- a/kitty_tests/options.py
+++ b/kitty_tests/options.py
@@ -157,14 +157,16 @@ class TestConfParsing(BaseTest):
         cb('linear(0, 0.25 25% 75%, 1)', first=EasingFunction('linear', linear_x=(0.0, 0.25, 0.75, 1.0), linear_y=(0, 0.25, 0.25, 1.0)))
 
         # test that easing functions give expected values
-        def ef(spec, tests, duration=0.5, accuracy=0):
+        def ef(spec, tests, only_single=True, duration=0.5, accuracy=0):
             cfv = p('cursor_blink_interval ' + spec).cursor_blink_interval
             self.set_options({'cursor_blink_interval': cfv})
             for t, expected in tests.items():
-                actual = test_cursor_blink_easing_function(t, duration)
+                actual = test_cursor_blink_easing_function(t, only_single, duration)
                 if abs(actual - expected) > accuracy:
                     self.ae(expected, actual, f'Failed for {spec=} with {t=}: {expected} != {actual}')
 
+        ef('linear', {0:1, 0.25: 0.5, 0.5: 0, 0.75: 0.5, 1: 1}, only_single=False)
+
         ef('linear(0, 0.25 25% 75%, 1)', {0: 0, 0.25: 0.25, 0.3: 0.25, 0.75: 0.25, 1:1})
         linear_vals = {0: 0, 1: 1, 0.1234: 0.1234, 0.6453: 0.6453}
         for spec in ('linear', 'linear(0, 1)', 'cubic-bezier(0, 0, 1, 1)', 'cubic-bezier(0.2, 0.2, 0.7, 0.7)'):