[core] Add unit test for TaggedString

test/text/tagged_string.test.cpp

@@ -4,6 +4,7 @@
 #include <mbgl/text/tagged_string.hpp>
 
 using namespace mbgl;
+using namespace std::literals;
 
 TEST(TaggedString, Trim) {
     TaggedString basic(u" \t\ntrim that and not this  \n\t", SectionOptions(1.0f, {}));
@@ -25,3 +26,19 @@ TEST(TaggedString, Trim) {
     noTrim.trim();
     EXPECT_EQ(noTrim.rawText(), u"no trim!");
 }
+
+TEST(TaggedString, MultipleSections) {
+    TaggedString oneSection(u"One section", SectionOptions(1.0f, {}));
+    EXPECT_FALSE(oneSection.hasMultipleUniqueSections());
+
+    TaggedString twoSections;
+    twoSections.addSection(u"first section", 1.5f, {});
+    twoSections.addSection(u"second section", 0.5f, {});
+    EXPECT_FALSE(twoSections.hasMultipleUniqueSections());
+
+    TaggedString multipleSections(u"", SectionOptions(1.0f, {}));
+    multipleSections.addSection(u"title", 1.5f, {"DIN Offc Pro Bold"s, "Arial Unicode MS Bold"s}, "header"s);
+    multipleSections.addSection(u"content", 1.5f, {"DIN Offc Pro Italic"s, "Arial Unicode MS Regular"s}, "footer"s);
+
+    EXPECT_TRUE(multipleSections.hasMultipleUniqueSections());
+}