From 25dcc2cabf7a40c5c10c33ade563d0fb0df9fa21 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Piotr=20B=C5=82a=C5=BCejewicz=20=28Peter=20Blazejewicz=29?=
 <peterblazejewicz@users.noreply.github.com>
Date: Mon, 13 Jan 2020 18:20:54 +0100
Subject: [PATCH] feat(chart.js): add 'sampleSize'. Closes #40775 (#41525)

Thanks!
---
 types/chart.js/chart.js-tests.ts | 4 +++-
 types/chart.js/index.d.ts        | 7 +++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/types/chart.js/chart.js-tests.ts b/types/chart.js/chart.js-tests.ts
index 6d38b51fd9..d4cb0b189e 100644
--- a/types/chart.js/chart.js-tests.ts
+++ b/types/chart.js/chart.js-tests.ts
@@ -68,6 +68,7 @@ const chart: Chart = new Chart(ctx, {
                 {
                     ticks: {
                         callback: Math.floor,
+                        sampleSize: 10,
                     },
                     gridLines: {
                         display: false,
@@ -266,7 +267,8 @@ const linearScaleChart: Chart = new Chart(ctx, {
                 distribution: 'series',
                 ticks: {
                     source: 'data',
-                    autoSkip: true
+                    autoSkip: true,
+                    sampleSize: 1,
                 }
             }],
             yAxes: [{
diff --git a/types/chart.js/index.d.ts b/types/chart.js/index.d.ts
index 1c1396ae03..5793bfbf1e 100644
--- a/types/chart.js/index.d.ts
+++ b/types/chart.js/index.d.ts
@@ -563,6 +563,13 @@ declare namespace Chart {
         mirror?: boolean;
         padding?: number;
         reverse?: boolean;
+        /**
+         * The number of ticks to examine when deciding how many labels will fit.
+         * Setting a smaller value will be faster, but may be less accurate
+         * when there is large variability in label length.
+         * Deault: `ticks.length`
+         */
+        sampleSize?: number;
         showLabelBackdrop?: boolean;
         source?: 'auto' | 'data' | 'labels';
         stepSize?: number;