Disallow comma in selector by default

build.gradle.kts

@@ -4,7 +4,7 @@ plugins {
 }
 
 group = "nl.astraeus"
-version = "0.4.20"
+version = "0.4.21"
 
 repositories {
     maven { setUrl("https://dl.bintray.com/kotlin/kotlin-eap") }

src/commonMain/kotlin/nl/astraeus/css/style/Style.kt

@@ -75,7 +75,8 @@ abstract class CssGenerator {
     namespace: String = "",
     indent: String = "",
     minified: Boolean = false,
-    warnOnRedeclaration: Boolean = true
+    warnOnRedeclaration: Boolean = true,
+    allowCommaInSelector: Boolean = false
   ): String {
     val builder = StringBuilder()
 
@@ -96,6 +97,10 @@ abstract class CssGenerator {
       css.append(finalStyle.generatePropertyCss("  $indent"))
 
       if (css.isNotBlank()) {
+        check (allowCommaInSelector || !name.contains(',')) {
+          "Comma is not allowed in selector (option is set in generateCss call)"
+        }
+
         builder.append("\n$namespace$name".trim())
 
         //builder.append("  $indent")
@@ -144,7 +149,11 @@ abstract class CssGenerator {
         builder.append("}\n\n")
       }
 
-      builder.append(finalStyle.generateCss("$namespace$name".trim(), indent))
+      builder.append(finalStyle.generateCss(
+        "$namespace$name".trim(),
+        indent,
+        allowCommaInSelector = allowCommaInSelector
+      ))
     }
 
     if (this is ConditionalStyle) {
@@ -161,7 +170,11 @@ abstract class CssGenerator {
 
             css(mediaStyle)
 
-            builder.append(mediaStyle.generateCss("", "  $indent"))
+            builder.append(mediaStyle.generateCss(
+              "",
+              "  $indent",
+              allowCommaInSelector = allowCommaInSelector
+            ))
           }
 
           builder.append(indent)
@@ -182,7 +195,11 @@ abstract class CssGenerator {
 
             css(mediaStyle)
 
-            builder.append(mediaStyle.generateCss("", "  $indent"))
+            builder.append(mediaStyle.generateCss(
+              "",
+              "  $indent",
+              allowCommaInSelector = allowCommaInSelector
+            ))
           }
 
           builder.append(indent)

src/commonTest/kotlin/nl/astraeus/css/TestCssBuilder.kt

@@ -12,6 +12,7 @@ import nl.astraeus.css.style.attrEquals
 import nl.astraeus.css.style.cls
 import nl.astraeus.css.style.id
 import kotlin.test.Test
+import kotlin.test.assertTrue
 
 class TestCssBuilder {
 
@@ -174,4 +175,38 @@ class TestCssBuilder {
 
     println(css.generateCss())
   }
+
+
+  @Test
+  fun testOrWithComma() {
+    val css = style {
+      select("h1") {
+        color(Color.blue)
+
+        select("table") {
+          color(Color.red)
+
+          select("th, td") {
+            color(Color.green)
+          }
+        }
+      }
+    }
+
+    var excepted = false
+    try {
+      println(css.generateCss())
+    } catch(e: Exception) {
+      excepted = true
+      assertTrue {
+        e is IllegalStateException
+      }
+      assertTrue {
+        e.message?.contains("Comma is not allowed in selector") ?: false
+      }
+    }
+    assertTrue {
+      excepted
+    }
+  }
 }