Fixes #4934. Enforces Wikimedia character blocklisting on media titles. (#4955)

app/src/test/kotlin/fr/free/nrw/commons/upload/UploadMediaDetailInputFilterTest.kt

@@ -0,0 +1,128 @@
+package fr.free.nrw.commons.upload
+
+import android.text.SpannableStringBuilder
+import fr.free.nrw.commons.TestCommonsApplication
+import org.junit.Assert
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import org.robolectric.annotation.LooperMode
+
+@RunWith(RobolectricTestRunner::class)
+@Config(sdk = [21], application = TestCommonsApplication::class)
+@LooperMode(LooperMode.Mode.PAUSED)
+class UploadMediaDetailInputFilterTest {
+
+    @Test
+    fun testFilterGeneric() {
+        val filter = UploadMediaDetailInputFilter()
+        val filters = arrayOf(filter)
+        val destination = SpannableStringBuilder("")
+        destination.filters = filters
+
+        val test: CharSequence = "test"
+        val expected = "test"
+        destination.insert(0, test)
+        Assert.assertEquals(destination.toString(), expected)
+    }
+
+    @Test
+    fun testFilterUnusualSpaces() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        //All unusual space characters
+        val tests = intArrayOf(0x00A0, 0x1680, 0x180E, 0x2000, 0x2005, 0x200B, 0x2028, 0x2029, 0x202F, 0x205F, 0x3000)
+        for (test: Int in tests) {
+            builder.insert(0, String(Character.toChars(test)))
+            Assert.assertEquals(builder.toString(), "")
+            builder.clear()
+        }
+    }
+
+    @Test
+    fun testFilterBiDiOverrides() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        //Sample of BiDI override characters
+        val tests = intArrayOf(0x202A, 0x202B, 0x202C, 0x202D, 0x202E)
+        for (test: Int in tests) {
+            builder.insert(0, String(Character.toChars(test)))
+            Assert.assertEquals(builder.toString(), "")
+            builder.clear()
+        }
+    }
+
+    @Test
+    fun testFilterControlCharacters() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        //Sample of control characters
+        val tests = intArrayOf(0x00, 0x08, 0x10, 0x18, 0x1F, 0x7F)
+        for (test: Int in tests) {
+            builder.insert(0, String(Character.toChars(test)))
+            Assert.assertEquals(builder.toString(), "")
+            builder.clear()
+        }
+    }
+
+    @Test
+    fun testFilterByteOrderMark() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        builder.insert(0, String(Character.toChars(0xFEFF)))
+        Assert.assertEquals(builder.toString(), "")
+        builder.clear()
+    }
+
+    @Test
+    fun testFilterSoftHyphen() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        builder.insert(0, String(Character.toChars(0x00AD)))
+        Assert.assertEquals(builder.toString(), "")
+        builder.clear()
+    }
+
+    @Test
+    fun testFilterSpecials() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        //Sample of surrogate and special characters
+        val tests = intArrayOf(0xE000, 0xE63F, 0xEC7E, 0xF2BD, 0xF8FF, 0xFFF0, 0xFFF4, 0xFFFC, 0xFFFF)
+        for (test: Int in tests) {
+            builder.insert(0, String(Character.toChars(test)))
+            Assert.assertEquals(builder.toString(), "")
+            builder.clear()
+        }
+    }
+
+    @Test
+    fun testFilterNonBasicPlane() {
+        val builder = SpannableStringBuilder("")
+        builder.filters = arrayOf(UploadMediaDetailInputFilter())
+
+        //Sample of characters over 5 hex places not in the Han set
+        val testsExclude = intArrayOf(0x1FFFF, 0x44444, 0xFFFFF)
+        for (test: Int in testsExclude) {
+            builder.insert(0, String(Character.toChars(test)))
+            Assert.assertEquals(builder.toString(), "")
+            builder.clear()
+        }
+
+        //Sample of characters over 5 hex places in the Han set
+        val testsInclude = intArrayOf(0x20000, 0x2B740, 0x2F800)
+        val expected = SpannableStringBuilder("")
+        for (test: Int in testsInclude) {
+            builder.insert(0, String(Character.toChars(test)))
+            expected.insert(0, String(Character.toChars(test)))
+        }
+        Assert.assertEquals(builder.toString(), expected.toString())
+    }
+}