fix strikethrough position for line_height != 1.0

docs/changelog.md

@@ -88,6 +88,7 @@ As features stabilize some brief notes about them will accumulate here.
 * Charselect and repl recency/history were not persisted across restarts. #4047 ?4019
 * macOS: system font fallback didn't always find a workable fallback font. #4099 #849
 * F13-F24 keys are now supported. Thanks to @ovidiu-ionescu! #3937
+* Strikethrough position was not centered when setting `line_height` #4196
 
 #### Updated
 * Bundled harfbuzz to 8.1.1

test-data/underlines.sh

@@ -1,6 +1,7 @@
 #!/bin/sh
 
 printf "\x1b[58:2::255:0:0m\x1b[4:1msingle\x1b[4:2mdouble\x1b[4:3mcurly\x1b[4:4mdotted\x1b[4:5mdashed\x1b[0m\n"
+printf "\x1b[9mStRiKeThRoUgH\x1b[0m\n"
 echo
 printf "\x1b[58:2::0:255:0m\x1b[53moverline\x1b[0m\n"
 

wezterm-gui/src/utilsprites.rs

@@ -111,7 +111,10 @@ impl RenderMetrics {
         let descender_plus_two =
             (2 * underline_height + descender_row).min(cell_height as isize - underline_height);
         let strike_row = match &config.strikethrough_position {
-            None => descender_row / 2,
+            None => {
+                ((cell_height as f64 + (metrics.descender.get() - underline_position)) / 2.)
+                    as isize
+            }
             Some(d) => d
                 .evaluate_as_pixels(DimensionContext {
                     dpi: fonts.get_dpi() as f32,