fonts: allow setting assume_emoji_presentation per font

This allows the user to specify what happens if they have an emoji
font that doesn't match our built-in heuristics.

config/src/font.rs

@@ -353,6 +353,8 @@ pub struct FontAttributes {
     pub freetype_load_flags: Option<FreeTypeLoadFlags>,
     #[dynamic(default)]
     pub scale: Option<NotNan<f64>>,
+    #[dynamic(default)]
+    pub assume_emoji_presentation: Option<bool>,
 }
 impl_lua_conversion_dynamic!(FontAttributes);
 
@@ -380,6 +382,7 @@ impl FontAttributes {
             freetype_render_target: None,
             freetype_load_flags: None,
             scale: None,
+            assume_emoji_presentation: None,
         }
     }
 
@@ -396,6 +399,7 @@ impl FontAttributes {
             freetype_render_target: None,
             freetype_load_flags: None,
             scale: None,
+            assume_emoji_presentation: None,
         }
     }
 }
@@ -414,6 +418,7 @@ impl Default for FontAttributes {
             freetype_render_target: None,
             freetype_load_flags: None,
             scale: None,
+            assume_emoji_presentation: None,
         }
     }
 }

config/src/lua.rs

@@ -327,6 +327,8 @@ struct LuaFontAttributes {
     pub freetype_load_flags: Option<String>,
     #[dynamic(default)]
     pub scale: Option<NotNan<f64>>,
+    #[dynamic(default)]
+    pub assume_emoji_presentation: Option<bool>,
 }
 impl<'lua> FromLua<'lua> for LuaFontAttributes {
     fn from_lua(value: Value<'lua>, _lua: &'lua Lua) -> Result<Self, mlua::Error> {
@@ -415,6 +417,7 @@ fn font<'lua>(
                 None => None,
             },
             scale: attrs.scale,
+            assume_emoji_presentation: attrs.assume_emoji_presentation,
         }));
 
     Ok(text_style)
@@ -465,6 +468,7 @@ fn font_with_fallback<'lua>(
                     None => None,
                 },
                 scale: attrs.scale,
+                assume_emoji_presentation: attrs.assume_emoji_presentation,
             }));
     }
 

docs/changelog.md

@@ -20,6 +20,7 @@ As features stabilize some brief notes about them will accumulate here.
 * [window:get_selection_escapes_for_pane](config/lua/window/get_selection_escapes_for_pane.md) method for getting the current selection including escape sequences. [#2223](https://github.com/wez/wezterm/issues/2223)
 * New [wezterm.gui](config/lua/wezterm.gui/index.md) module and [mux_window:gui_window](config/lua/mux-window/gui_window.md) method.
 * You may now use [wezterm.format](config/lua/wezterm/format.md) (or otherwise use strings with escape sequences) in the labels of the [Launcher Menu](config/launch.md#the-launcher-menu).
+* You may now specify `assume_emoji_presentation = true` (or `false`) in [wezterm.font()](config/lua/wezterm/font.md) and [wezterm.font_with_fallback()](config/lua/wezterm/font_with_fallback.md)
 
 #### Fixed
 * [ActivateKeyTable](config/lua/keyassignment/ActivateKeyTable.md)'s `replace_current` field was not actually optional. Made it optional. [#2179](https://github.com/wez/wezterm/issues/2179)

docs/config/lua/wezterm/font.md

@@ -93,6 +93,7 @@ The following options can be specified in the same way:
 * [freetype_load_target](../config/freetype_load_target.md)
 * [freetype_render_target](../config/freetype_render_target.md)
 * [freetype_load_flags](../config/freetype_load_flags.md)
+* `assume_emoji_presentation = true` or `assume_emoji_presentation = false` to control whether a font is considered to have emoji (rather than text) presentation glyphs for emoji. (*Since: nightly builds only)
 
 *Since: 20220319-142410-0fcdea07*
 

docs/config/lua/wezterm/font_with_fallback.md

@@ -65,6 +65,7 @@ The following options can be specified in the same way:
 * [freetype_load_target](../config/freetype_load_target.md)
 * [freetype_render_target](../config/freetype_render_target.md)
 * [freetype_load_flags](../config/freetype_load_flags.md)
+* `assume_emoji_presentation = true` or `assume_emoji_presentation = false` to control whether a font is considered to have emoji (rather than text) presentation glyphs for emoji. (*Since: nightly builds only)
 
 ## Dealing with different fallback font heights
 

wezterm-font/src/locator/core_text.rs

@@ -198,6 +198,7 @@ fn build_fallback_list_impl() -> anyhow::Result<Vec<ParsedFont>> {
         freetype_render_target: None,
         freetype_load_flags: None,
         scale: None,
+        assume_emoji_presentation: None,
     };
     if let Ok(descriptors) = descriptor_from_attr(&symbols) {
         for descriptor in descriptors.iter() {

wezterm-font/src/locator/gdi.rs

@@ -328,6 +328,7 @@ impl FontLocator for GdiFontLocator {
                         freetype_render_target: None,
                         freetype_load_flags: None,
                         scale: None,
+                        assume_emoji_presentation: None,
                     };
 
                     if !resolved.contains(&attr) {

wezterm-font/src/parser.rs

@@ -666,6 +666,11 @@ impl ParsedFont {
             && attr.weight < self.weight
             && self.weight >= FontWeight::REGULAR;
 
+        match attr.assume_emoji_presentation {
+            Some(assume) => {
+                self.assume_emoji_presentation = assume;
+            }
+            None => {
                 // If they explicitly list an emoji font, assume that they
                 // want it to be used for emoji presentation.
                 // We match on "moji" rather than "emoji" as there are
@@ -677,6 +682,8 @@ impl ParsedFont {
                 {
                     self.assume_emoji_presentation = true;
                 }
+            }
+        }
 
         self
     }

wezterm-font/src/shaper/harfbuzz.rs

@@ -702,6 +702,7 @@ mod test {
                     freetype_render_target: None,
                     harfbuzz_features: None,
                     scale: None,
+                    assume_emoji_presentation: None,
                 },
                 14,
             )