handle CSS declarations with multiple selectors

Author: swhitty

DOM/Sources/Parser.XML.Scanner.swift

@@ -55,7 +55,14 @@ package extension XMLParser {
         package mutating func scanStringIfPossible(_ token: String) -> Bool {
             return (try? self.scanString(token)) == true
         }
-        
+
+        @discardableResult
+        package mutating func nextScanString(_ token: String) -> Bool {
+            scanner.currentIndex = currentIndex
+            defer { scanner.currentIndex  = currentIndex }
+            return scanStringIfPossible(token)
+        }
+
         package mutating func scanString(matchingAny tokens: Set<String>) throws -> String {
             scanner.currentIndex = currentIndex
             guard let match = tokens.first(where: { scanner.scanString($0) != nil }) else {

DOM/Tests/Parser.XML.StyleSheetTests.swift

@@ -110,4 +110,43 @@ final class ParserXMLStyleSheetTests: XCTestCase {
         XCTAssertEqual(sheet[.class("b")]?.fill, .color(.keyword(.blue)))
         XCTAssertEqual(sheet[.element("rect")]?.fill, .color(.keyword(.pink)))
     }
+
+    func testMergesSelectors() throws {
+        let entries = try XMLParser.parseEntries(
+            """
+            .a {
+               fill: red;
+            }
+            .a {
+               stroke: blue;
+            }
+            .a {
+               fill: purple;
+            }
+            """
+        )
+
+        XCTAssertEqual(
+            entries,
+            [.class("a"): ["fill": "purple", "stroke": "blue"]]
+        )
+    }
+
+    func testMutlipleSelectors() throws {
+        let entries = try XMLParser.parseEntries(
+            """
+            .a, .b {
+               fill: red;
+            }
+            """
+        )
+
+        XCTAssertEqual(
+            entries,
+            [
+                .class("a"): ["fill": "red"],
+                .class("b"): ["fill": "red"]
+            ]
+        )
+    }
 }

Examples/Sources/GalleryView.swift

@@ -52,7 +52,8 @@ struct GalleryView: View {
             "yawning.svg",
             "thats-no-moon.svg",
             "alert.svg",
-            "effigy.svg"
+            "effigy.svg",
+            "stylesheet-multiple.svg"
         ].compactMap {
             SVG(named: $0, in: .samples)
         }