IssueTracker

I'm trying to write and test a ResourceXmlDetector to check for cases where textAppearance styles contain style items which will be ignored using AGP 3.1.0-beta4 and Lint 26.1.0-beta4.

I expected the following test to fail:

  @Test
  fun failLint() {
    lint()
        .files(
            xml(
                "res/values/styles.xml",
                """
                |<?xml version="1.0" encoding="utf-8"?>
                |<resources>
                |  <style name="TextAppearance">
                |    <item name="android:lineSpacingMultiplier">1.33</item>
                |  </style>
                |</resources>
                |/>
                """.trimMargin()
            ),
            xml(
                "res/layout/layout.xml",
                """
                |<?xml version="1.0" encoding="utf-8"?>
                |<TextView
                |   android:textAppearance="@style/TextAppearance"
                |/>
                """.trimMargin()
            )
        )
        .issues(ISSUE_STYLE_ITEM)
        .run()
        .expectClean()
  }

but it instead succeeded.  

Attaching a debugger and digging into org.apache.xerces.internal.parsers.XML11Configuration#parse(boolean), I entered a catch block and introspected the exception to find: "::::4:3:-1:The prefix "android" for attribute "android:textAppearance" associated with an element type "TextView" is not bound." -- a helpful debugging message.

Unfortunately, this exception is swallowed and ignored in LintCliXmlParser.parseXml(CharSequence, File) returning null.  Its caller LintDriver#checkResourceFolder uses this null XmlContext as a sign to stop processing the current xml file and continue on to the next XmlFile in the iterated set (line 1679).  

Instead, I would have expected the XML processing to fail, bubbling up to my test and resulting in a failure.