Merge pull request #303 from Kotlin/escaping-backslash-html

[Bug fix] "SyntaxError: Invalid hexadecimal escape sequence" for rendering DataFrames with "\" in content

Author: Jolanrensen

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/io/html.kt

@@ -261,7 +261,7 @@ internal fun String.escapeHTML(): String {
     val str = this
     return buildString {
         for (c in str) {
-            if (c.code > 127 || c == '"' || c == '\'' || c == '<' || c == '>' || c == '&') {
+            if (c.code > 127 || c == '"' || c == '\'' || c == '<' || c == '>' || c == '&' || c == '\\') {
                 append("&#")
                 append(c.code)
                 append(';')

core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/rendering/RenderingTests.kt

@@ -56,6 +56,13 @@ class RenderingTests {
         html shouldContain "<Air France>"
     }
 
+    @Test
+    fun unicodeEscapeSequencesAreEscaped() {
+        val df = dataFrameOf("content")("""Hello\nfrom \x and \y""")
+        val html = df.toHTML().toString()
+        html shouldContain "Hello\nfrom \x and \y"
+    }
+
     @Test
     fun `long text is trimmed without escaping`() {
         val df = dataFrameOf("text")("asdfkjasdlkjfhasljkddasdasdasdasdasdasdhf")