Refactor conditional check and update draftlog

Author: camdecoster

draftlogs/7507_fix.md

@@ -1 +1 @@
-Fix `histogram` autobin size for single-point traces in `overlay` mode on data updates via `Plotly.react` [[#7507](https://github.com/plotly/plotly.js/pull/7507)]
+Fix `histogram` autobin size for single-point traces in `overlay` mode on data updates via `Plotly.react` [[#7507](https://github.com/plotly/plotly.js/pull/7507)], with thanks to @Lexachoc for the contribution!

src/traces/histogram/calc.js

@@ -328,10 +328,9 @@ function calcAllAutoBins(gd, trace, pa, mainData, _overlayEdgeCase) {
         // Edge case: single-valued histogram overlaying others
         // Use them all together to calculate the bin size for the single-valued one
         // Don't re-calculate bin width if user manually specified it
-        // Check if bingroup or bin size is defined
         if(isOverlay && !Registry.traceIs(trace, '2dMap') && newBinSpec._dataSpan === 0 &&
         pa.type !== 'category' && pa.type !== 'multicategory' &&
-        trace.bingroup === '' && trace._input?.[binAttr]?.size === undefined) {
+        trace.bingroup === '' && !trace._input[binAttr]?.size) {
             // Several single-valued histograms! Stop infinite recursion,
             // just return an extra flag that tells handleSingleValueOverlays
             // to sort out this trace too