Expose ICUs u_hasBinaryProperty (#1029)

This is needed to detect emojis in Compose Multiplatform.

Also, it looks like the native implementations of
`String.intCodePoints()` were broken. I fixed them by copying the
relevant code from Compose.

skiko/src/commonMain/kotlin/org/jetbrains/skia/CodePoint.kt

+package org.jetbrains.skia
+
+// TODO Remove once it's available in common stdlib https://youtrack.jetbrains.com/issue/KT-23251
+internal typealias CodePoint = Int
+
+/**
+ * The minimum value of a supplementary code point, `\u0x10000`.
+ */
+private const val MIN_SUPPLEMENTARY_CODE_POINT: Int = 0x10000
+
+/**
+ * Converts a surrogate pair to a unicode code point.
+ */
+internal fun toCodePoint(high: Char, low: Char): CodePoint =
+    (((high - Char.MIN_HIGH_SURROGATE) shl 10) or (low - Char.MIN_LOW_SURROGATE)) + MIN_SUPPLEMENTARY_CODE_POINT
+
+internal fun Int.charCount(): Int = if (this >= MIN_SUPPLEMENTARY_CODE_POINT) 2 else 1
+
+internal val CharSequence.codePoints
+    get() = codePointsAt(0)
+
+internal fun CharSequence.codePointsAt(index: Int) = sequence {
+    var current = index
+    while (current < length) {
+        val codePoint = codePointAt(current)
+        yield(codePoint)
+        current += codePoint.charCount()
+    }
+}
+
+internal val CharSequence.codePointsAsIntArray: IntArray
+    get() = codePoints.toList().toIntArray()
+
+/**
+ * Returns the character (Unicode code point) at the specified index.
+ */
+internal fun CharSequence.codePointAt(index: Int): CodePoint {
+    val high = this[index]
+    if (high.isHighSurrogate() && index + 1 < this.length) {
+        val low = this[index + 1]
+        if (low.isLowSurrogate()) {
+            return toCodePoint(high, low)
+        }
+    }
+    return high.code
+}

skiko/src/commonMain/kotlin/org/jetbrains/skia/Expects.kt

@@ -2,8 +2,6 @@ package org.jetbrains.skia
 
 internal expect fun <R> commonSynchronized(lock: Any, block: () -> R)
 
-internal expect fun String.intCodePoints(): IntArray
-
 internal expect fun defaultLanguageTag(): String
 
 expect class Pattern {

skiko/src/commonMain/kotlin/org/jetbrains/skia/Font.kt

@@ -336,7 +336,7 @@ class Font : Managed {
      * @return  the corresponding glyph ids for each character.
      */
     fun getStringGlyphs(s: String): ShortArray {
-        return getUTF32Glyphs(s.intCodePoints())
+        return getUTF32Glyphs(s.codePointsAsIntArray)
     }
 
     /**

skiko/src/commonMain/kotlin/org/jetbrains/skia/Typeface.kt

@@ -169,7 +169,7 @@ class Typeface internal constructor(ptr: NativePointer) : RefCnt(ptr) {
      * @return  the corresponding glyph ids for each character.
      */
     fun getStringGlyphs(s: String): ShortArray {
-        return getUTF32Glyphs(s.intCodePoints())
+        return getUTF32Glyphs(s.codePointsAsIntArray)
     }
 
     /**

skiko/src/commonMain/kotlin/org/jetbrains/skia/icu/Unicode.kt

 package org.jetbrains.skia.icu
 
-import org.jetbrains.skia.ExternalSymbolName
-import org.jetbrains.skia.ModuleImport
+import org.jetbrains.skia.*
 import org.jetbrains.skia.impl.Library.Companion.staticLoad
+import org.jetbrains.skia.impl.Stats
 
 /**
  * CharDirection represents Bidi_Class Unicode character property.
@@ -11,6 +11,7 @@ import org.jetbrains.skia.impl.Library.Companion.staticLoad
  * See https://unicode-org.github.io/icu-docs/apidoc/dev/icu4c/uchar_8h.html
  * See https://www.unicode.org/reports/tr9/
  */
+@Suppress("MemberVisibilityCanBePrivate", "unused", "SpellCheckingInspection")
 object CharDirection {
     init {
         staticLoad()
@@ -44,9 +45,151 @@ object CharDirection {
      * Returns the bidirectional category value for the code point.
      * Same as java.lang.Character.getDirectionality()
      */
-    fun of(codePoint: Int): Int = charDirection(codePoint)
+    fun of(codePoint: Int): Int {
+        Stats.onNativeCall()
+        return _nCharDirection(codePoint)
+    }
 }
 
-@ExternalSymbolName("org_jetbrains_skia_icu_Unicode_charDirection")
-@ModuleImport("./skiko.mjs", "org_jetbrains_skia_icu_Unicode_charDirection")
-private external fun charDirection(codePoint: Int): Int
+/**
+ * Bundles functions to inspect Unicode character properties.
+ */
+@Suppress("MemberVisibilityCanBePrivate", "unused", "SpellCheckingInspection")
+object CharProperties {
+    init {
+        staticLoad()
+    }
+
+    const val ALPHABETIC = 0
+    const val BINARY_START = ALPHABETIC
+    const val ASCII_HEX_DIGIT = 1
+    const val BIDI_CONTROL = 2
+    const val BIDI_MIRRORED = 3
+    const val DASH = 4
+    const val DEFAULT_IGNORABLE_CODE_POINT = 5
+    const val DEPRECATED = 6
+    const val DIACRITIC = 7
+    const val EXTENDER = 8
+    const val FULL_COMPOSITION_EXCLUSION = 9
+    const val GRAPHEME_BASE = 10
+    const val GRAPHEME_EXTEND = 11
+    const val GRAPHEME_LINK = 12
+    const val HEX_DIGIT = 13
+    const val HYPHEN = 14
+    const val ID_CONTINUE = 15
+    const val ID_START = 16
+    const val IDEOGRAPHIC = 17
+    const val IDS_BINARY_OPERATOR = 18
+    const val IDS_TRINARY_OPERATOR = 19
+    const val JOIN_CONTROL = 20
+    const val LOGICAL_ORDER_EXCEPTION = 21
+    const val LOWERCASE = 22
+    const val MATH = 23
+    const val NONCHARACTER_CODE_POINT = 24
+    const val QUOTATION_MARK = 25
+    const val RADICAL = 26
+    const val SOFT_DOTTED = 27
+    const val TERMINAL_PUNCTUATION = 28
+    const val UNIFIED_IDEOGRAPH = 29
+    const val UPPERCASE = 30
+    const val WHITE_SPACE = 31
+    const val XID_CONTINUE = 32
+    const val XID_START = 33
+    const val CASE_SENSITIVE = 34
+    const val S_TERM = 35
+    const val VARIATION_SELECTOR = 36
+    const val NFD_INERT = 37
+    const val NFKD_INERT = 38
+    const val NFC_INERT = 39
+    const val NFKC_INERT = 40
+    const val SEGMENT_STARTER = 41
+    const val PATTERN_SYNTAX = 42
+    const val PATTERN_WHITE_SPACE = 43
+    const val POSIX_ALNUM = 44
+    const val POSIX_BLANK = 45
+    const val POSIX_GRAPH = 46
+    const val POSIX_PRINT = 47
+    const val POSIX_XDIGIT = 48
+    const val CASED = 49
+    const val CASE_IGNORABLE = 50
+    const val CHANGES_WHEN_LOWERCASED = 51
+    const val CHANGES_WHEN_UPPERCASED = 52
+    const val CHANGES_WHEN_TITLECASED = 53
+    const val CHANGES_WHEN_CASEFOLDED = 54
+    const val CHANGES_WHEN_CASEMAPPED = 55
+    const val CHANGES_WHEN_NFKC_CASEFOLDED = 56
+    const val EMOJI = 57
+    const val EMOJI_PRESENTATION = 58
+    const val EMOJI_MODIFIER = 59
+    const val EMOJI_MODIFIER_BASE = 60
+    const val EMOJI_COMPONENT = 61
+    const val REGIONAL_INDICATOR = 62
+    const val PREPENDED_CONCATENATION_MARK = 63
+    const val EXTENDED_PICTOGRAPHIC = 64
+    const val BIDI_CLASS = 0x1000
+    const val INT_START = BIDI_CLASS
+    const val BLOCK = 0x1001
+    const val CANONICAL_COMBINING_CLASS = 0x1002
+    const val DECOMPOSITION_TYPE = 0x1003
+    const val EAST_ASIAN_WIDTH = 0x1004
+    const val GENERAL_CATEGORY = 0x1005
+    const val JOINING_GROUP = 0x1006
+    const val JOINING_TYPE = 0x1007
+    const val LINE_BREAK = 0x1008
+    const val NUMERIC_TYPE = 0x1009
+    const val SCRIPT = 0x100A
+    const val HANGUL_SYLLABLE_TYPE = 0x100B
+    const val NFD_QUICK_CHECK = 0x100C
+    const val NFKD_QUICK_CHECK = 0x100D
+    const val NFC_QUICK_CHECK = 0x100E
+    const val NFKC_QUICK_CHECK = 0x100F
+    const val LEAD_CANONICAL_COMBINING_CLASS = 0x1010
+    const val TRAIL_CANONICAL_COMBINING_CLASS = 0x1011
+    const val GRAPHEME_CLUSTER_BREAK = 0x1012
+    const val SENTENCE_BREAK = 0x1013
+    const val WORD_BREAK = 0x1014
+    const val BIDI_PAIRED_BRACKET_TYPE = 0x1015
+    const val INDIC_POSITIONAL_CATEGORY = 0x1016
+    const val INDIC_SYLLABIC_CATEGORY = 0x1017
+    const val VERTICAL_ORIENTATION = 0x1018
+    const val GENERAL_CATEGORY_MASK = 0x2000
+    const val MASK_START = GENERAL_CATEGORY_MASK
+    const val NUMERIC_VALUE = 0x3000
+    const val DOUBLE_START = NUMERIC_VALUE
+    const val AGE = 0x4000
+    const val STRING_START = AGE
+    const val BIDI_MIRRORING_GLYPH = 0x4001
+    const val CASE_FOLDING = 0x4002
+    const val LOWERCASE_MAPPING = 0x4004
+    const val NAME = 0x4005
+    const val SIMPLE_CASE_FOLDING = 0x4006
+    const val SIMPLE_LOWERCASE_MAPPING = 0x4007
+    const val SIMPLE_TITLECASE_MAPPING = 0x4008
+    const val SIMPLE_UPPERCASE_MAPPING = 0x4009
+    const val TITLECASE_MAPPING = 0x400A
+    const val UPPERCASE_MAPPING = 0x400C
+    const val BIDI_PAIRED_BRACKET = 0x400D
+    const val SCRIPT_EXTENSIONS = 0x7000
+    const val OTHER_PROPERTY_START = SCRIPT_EXTENSIONS
+    const val INVALID_CODE   = -1
+
+    /**
+     * Returns whether the given codepoint has the given binary property.
+     *
+     * @param codePoint The codepoint.
+     * @param property A binary property; one of the constants defined in [CharProperties].
+     */
+    fun codePointHasBinaryProperty(codePoint: Int, property: Int): Boolean {
+        Stats.onNativeCall()
+        return _nCodePointHasBinaryProperty(codePoint, property)
+    }
+}
+
+@ExternalSymbolName("org_jetbrains_skia_icu_Unicode__1nCharDirection")
+@ModuleImport("./skiko.mjs", "org_jetbrains_skia_icu_Unicode__1nCharDirection")
+private external fun _nCharDirection(codePoint: Int): Int
+
+@ExternalSymbolName("org_jetbrains_skia_icu_Unicode__1nCodePointHasBinaryProperty")
+@ModuleImport("./skiko.mjs", "org_jetbrains_skia_icu_Unicode__1nCodePointHasBinaryProperty")
+private external fun _nCodePointHasBinaryProperty(codePoint: Int, property: Int): Boolean
+

skiko/src/commonTest/kotlin/org/jetbrains/skia/icu/UnicodeTest.kt

 package org.jetbrains.skia.icu
 
+import org.jetbrains.skia.codePoints
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
 
 class UnicodeTest {
-
     @Test
     fun directionality() {
         assertEquals(CharDirection.EUROPEAN_NUMBER, CharDirection.of('0'.code)) // Number
@@ -12,4 +14,20 @@ class UnicodeTest {
         assertEquals(CharDirection.RIGHT_TO_LEFT, CharDirection.of('א'.code)) // Hebrew
         assertEquals(CharDirection.RIGHT_TO_LEFT_ARABIC, CharDirection.of('؈'.code)) // Arabic
     }
+
+    @Test
+    fun binaryProperties() {
+        fun String.firstCodePointHasProperty(property: Int): Boolean {
+            val codePoint = this.codePoints.first()
+            println(codePoint.toString(16))
+            return CharProperties.codePointHasBinaryProperty(codePoint, property)
+        }
+
+        assertTrue("⌚".firstCodePointHasProperty(CharProperties.EMOJI))
+        assertTrue("✅".firstCodePointHasProperty(CharProperties.EMOJI_PRESENTATION))
+        assertTrue("♥️".firstCodePointHasProperty(CharProperties.EXTENDED_PICTOGRAPHIC))
+        assertTrue("🇮🇱".firstCodePointHasProperty(CharProperties.EMOJI))  // flag
+
+        assertFalse("x".firstCodePointHasProperty(CharProperties.EMOJI))
+    }
 }
\ No newline at end of file

skiko/src/jsWasmMain/kotlin/org/jetbrains/skia/Actuals.js.kt

@@ -6,8 +6,6 @@ internal actual fun <R> commonSynchronized(lock: Any, block: () -> R) {
     block()
 }
 
-actual fun String.intCodePoints(): IntArray = IntArray(this.length) { this[it].code }
-
 actual class Pattern constructor(regex: String) {
     private val _regex = Regex(regex)
 

skiko/src/jvmMain/cpp/common/icu/Unicode.cc

 #include <jni.h>
 #include "third_party/externals/icu/source/common/unicode/uchar.h"
 
-extern "C" JNIEXPORT jint JNICALL Java_org_jetbrains_skia_icu_UnicodeKt_charDirection
+extern "C" JNIEXPORT jint JNICALL Java_org_jetbrains_skia_icu_UnicodeKt__1nCharDirection
   (JNIEnv* env, jclass jclass, jint codePoint) {
     return u_charDirection(codePoint);
 }
+
+extern "C" JNIEXPORT jboolean JNICALL Java_org_jetbrains_skia_icu_UnicodeKt__1nCodePointHasBinaryProperty
+    (JNIEnv* env, jclass jclass, jint codePoint, jint property) {
+   return u_hasBinaryProperty(codePoint, (UProperty)property);
+}
\ No newline at end of file

skiko/src/jvmMain/kotlin/org/jetbrains/skia/Actuals.jvm.kt

@@ -6,8 +6,6 @@ internal actual fun <R> commonSynchronized(lock: Any, block: () -> R) {
     synchronized(lock, block)
 }
 
-internal actual fun String.intCodePoints(): IntArray = this.codePoints().toArray()
-
 actual typealias Pattern = java.util.regex.Pattern
 
 actual typealias Matcher = java.util.regex.Matcher

skiko/src/nativeJsMain/cpp/icu/Unicode.cc

 #include "common.h"
 #include "third_party/externals/icu/source/common/unicode/uchar.h"
 
-SKIKO_EXPORT KInt org_jetbrains_skia_icu_Unicode_charDirection(KInt codePoint) {
+SKIKO_EXPORT KInt org_jetbrains_skia_icu_Unicode__1nCharDirection(KInt codePoint) {
     return u_charDirection(codePoint);
 }
+
+SKIKO_EXPORT KBoolean org_jetbrains_skia_icu_Unicode__1nCodePointHasBinaryProperty(KInt codePoint, KInt property) {
+    return u_hasBinaryProperty(codePoint, (UProperty)property);
+}

skiko/src/nativeMain/kotlin/org/jetbrains/skia/Actuals.native.kt

@@ -9,8 +9,6 @@ internal actual fun <R> commonSynchronized(lock: Any, block: () -> R) {
     block()
 }
 
-internal actual fun String.intCodePoints(): IntArray = IntArray(this.length) { this[it].code }
-
 actual class Pattern constructor(regex: String) {
     private val _regex = Regex(regex)