[core] Add possibility of overriding paint properties inside format expression #14062

* [core] Add format override expression and formatted section to evaluation context

* [core] Add textColor to TaggedString's formatted section

* [core] Add FormatSectionOverrides and introduce overridable properties

* [core] Populate symbol layer paint properties for text sections

* [core] Add benchmark for style that uses text-color override

* [core] Add unit test for FormatOverrideExpression

* [core] Add unit test for FormatSectionOverrides

1 files changed, 11 insertions, 4 deletions

diff --git a/src/mbgl/style/layers/symbol_layer_impl.cpp b/src/mbgl/style/layers/symbol_layer_impl.cpp
index 3dd1da1136..e35e7b0b9f 100644
--- a/src/mbgl/style/layers/symbol_layer_impl.cpp
+++ b/src/mbgl/style/layers/symbol_layer_impl.cpp
@@ -1,17 +1,24 @@
 #include <mbgl/style/layers/symbol_layer_impl.hpp>
-
 #include <mbgl/util/logging.hpp>
 
 namespace mbgl {
 namespace style {
 
+bool SymbolLayer::Impl::hasFormatSectionOverrides() const {
+    if (!hasFormatSectionOverrides_) {
+        hasFormatSectionOverrides_ = SymbolLayerPaintPropertyOverrides::hasOverrides(layout.get<TextField>());
+    }
+    return *hasFormatSectionOverrides_;
+}
+
 bool SymbolLayer::Impl::hasLayoutDifference(const Layer::Impl& other) const {
     assert(other.getTypeInfo() == getTypeInfo());
     const auto& impl = static_cast<const style::SymbolLayer::Impl&>(other);
     return filter     != impl.filter ||
            visibility != impl.visibility ||
            layout     != impl.layout ||
-           paint.hasDataDrivenPropertyDifference(impl.paint);
+           paint.hasDataDrivenPropertyDifference(impl.paint) ||
+           (hasFormatSectionOverrides() && SymbolLayerPaintPropertyOverrides::hasPaintPropertyDifference(paint, impl.paint));
 }
 
 void SymbolLayer::Impl::populateFontStack(std::set<FontStack>& fontStack) const {
@@ -20,10 +27,10 @@ void SymbolLayer::Impl::populateFontStack(std::set<FontStack>& fontStack) const
     }
 
     layout.get<TextFont>().match(
-        [&] (Undefined) {
+        [&fontStack] (Undefined) {
             fontStack.insert({"Open Sans Regular", "Arial Unicode MS Regular"});
         },
-        [&] (const FontStack& constant) {
+        [&fontStack] (const FontStack& constant) {
             fontStack.insert(constant);
         },
         [&] (const auto& function) {