Fix `override_text_color` priority (#7439)

The override_text_color is now used when rendering text from a String or
&str. This is consistent with the RichText variant and makes the option
behave as advertised, taking precedence over WidgetVisuals and
overriding the color for all text unless explicitly changed for a single
widget (via RichText or LayoutJob).

* Closes <https://github.com/emilk/egui/issues/7367>
* [x] I have followed the instructions in the PR template

---------

Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>

crates/egui/src/widget_text.rs

@@ -746,13 +746,17 @@ impl WidgetText {
     ) -> Arc<Galley> {
         match self {
             Self::Text(text) => {
+                let color = style
+                    .visuals
+                    .override_text_color
+                    .unwrap_or(crate::Color32::PLACEHOLDER);
                 let mut layout_job = LayoutJob::simple_format(
                     text,
                     TextFormat {
                         // We want the style overrides to take precedence over the fallback font
                         font_id: FontSelection::default()
                             .resolve_with_fallback(style, fallback_font),
-                        color: crate::Color32::PLACEHOLDER,
+                        color,
                         valign: default_valign,
                         ..Default::default()
                     },

crates/egui_kittest/tests/regression_tests.rs

@@ -157,3 +157,33 @@ pub fn slider_should_move_with_fixed_decimals() {
     let actual_slider = harness.get_by_role(accesskit::Role::SpinButton);
     assert_eq!(actual_slider.value(), Some("1.00".to_owned()));
 }
+
+#[test]
+pub fn override_text_color_affects_interactive_widgets() {
+    use egui::{Color32, RichText};
+
+    let mut harness = Harness::new_ui(|ui| {
+        _ = ui.button("normal");
+        _ = ui.checkbox(&mut true, "normal");
+        _ = ui.radio(true, "normal");
+        ui.visuals_mut().widgets.inactive.fg_stroke.color = Color32::RED;
+        _ = ui.button("red");
+        _ = ui.checkbox(&mut true, "red");
+        _ = ui.radio(true, "red");
+        // override_text_color takes precedence over `WidgetVisuals`, as it docstring claims
+        ui.visuals_mut().override_text_color = Some(Color32::GREEN);
+        _ = ui.button("green");
+        _ = ui.checkbox(&mut true, "green");
+        _ = ui.radio(true, "green");
+        // Setting the color explicitly with `RichText` overrides style
+        _ = ui.button(RichText::new("blue").color(Color32::BLUE));
+        _ = ui.checkbox(&mut true, RichText::new("blue").color(Color32::BLUE));
+        _ = ui.radio(true, RichText::new("blue").color(Color32::BLUE));
+    });
+
+    #[cfg(all(feature = "wgpu", feature = "snapshot"))]
+    let mut results = SnapshotResults::new();
+
+    #[cfg(all(feature = "wgpu", feature = "snapshot"))]
+    results.add(harness.try_snapshot("override_text_color_interactive"));
+}

crates/egui_kittest/tests/snapshots/override_text_color_interactive.png

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:60540cb1b5b71f100b2ea367a939cb9d93a91e56ff1f14ebfc988bbe79d69ac7
+size 19719