Bug 1647377 - Provide basic line-breaking support for Tibetan on Android by treating TSHEG like a hyphen. r=m_kato

Differential Revision: https://phabricator.services.mozilla.com/D81441

intl/lwbrk/LineBreaker.cpp

@@ -367,10 +367,18 @@ static inline bool IS_NONBREAKABLE_SPACE(char16_t u) {
 }
 
 static inline bool IS_HYPHEN(char16_t u) {
-  return (u == U_HYPHEN || u == 0x058A ||  // ARMENIAN HYPHEN
-          u == 0x2010 ||                   // HYPHEN
+  return (u == U_HYPHEN || u == 0x2010 ||  // HYPHEN
           u == 0x2012 ||                   // FIGURE DASH
-          u == 0x2013);                    // EN DASH
+          u == 0x2013 ||                   // EN DASH
+#if ANDROID
+          /* Bug 1647377: On Android, we don't have a "platform" backend
+           * that supports Tibetan (nsRuleBreaker.cpp only knows about
+           * Thai), so instead we just treat the TSHEG like a hyphen to
+           * provide basic line-breaking possibilities.
+           */
+          u == 0x0F0B ||  // TIBETAN MARK INTERSYLLABIC TSHEG
+#endif
+          u == 0x058A);  // ARMENIAN HYPHEN
 }
 
 static int8_t GetClass(uint32_t u, LineBreaker::Strictness aLevel,
@@ -618,8 +626,10 @@ static int8_t GetClass(uint32_t u, LineBreaker::Strictness aLevel,
         return GETCLASSFROMTABLE(gLBClass00, uint16_t(U_HYPHEN));
       }
     } else if (0x0F00 == h) {
-      if (0x08 == l || 0x0C == l || 0x12 == l) {
-        return CLASS_NON_BREAKABLE;
+      // Tibetan chars with class = BA
+      if (0x34 == l || 0x7f == l || 0x85 == l || 0xbe == l || 0xbf == l ||
+          0xd2 == l) {
+        return CLASS_BREAKABLE;
       }
     } else if (0x1800 == h) {
       if (0x0E == l) {

intl/lwbrk/LineBreaker.h

@@ -72,8 +72,14 @@ static inline bool NS_IsSpace(char16_t u) {
 }
 
 static inline bool NS_NeedsPlatformNativeHandling(char16_t aChar) {
-  return (0x0e01 <= aChar && aChar <= 0x0fff) ||  // Thai, Lao, Tibetan
-         (0x1780 <= aChar && aChar <= 0x17ff);    // Khmer
+  return
+#if ANDROID  // Bug 1647377: no "platform native" support for Tibetan;
+             // better to just use our class-based breaker.
+      (0x0e01 <= aChar && aChar <= 0x0eff) ||  // Thai, Lao
+#else
+      (0x0e01 <= aChar && aChar <= 0x0fff) ||  // Thai, Lao, Tibetan
+#endif
+      (0x1780 <= aChar && aChar <= 0x17ff);  // Khmer
 }
 
 }  // namespace intl

testing/web-platform/meta/css/css-text/i18n/css3-text-line-break-baspglwj-082.html.ini

@@ -1,13 +1,20 @@
 [css3-text-line-break-baspglwj-082.html]
   [white-space:pre-wrap]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:pre-line]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:break-spaces]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:normal]
-    expected: FAIL
-
+    expected:
+      if os == "android": PASS
+      FAIL

testing/web-platform/meta/css/css-text/i18n/css3-text-line-break-baspglwj-126.html.ini

@@ -1,13 +1,21 @@
 [css3-text-line-break-baspglwj-126.html]
   [white-space:pre-wrap]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:pre-line]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:break-spaces]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:normal]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 

testing/web-platform/meta/css/css-text/i18n/css3-text-line-break-baspglwj-127.html.ini

@@ -1,13 +1,21 @@
 [css3-text-line-break-baspglwj-127.html]
   [white-space:pre-wrap]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:pre-line]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:break-spaces]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:normal]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 

testing/web-platform/meta/css/css-text/i18n/css3-text-line-break-baspglwj-128.html.ini

@@ -1,13 +1,21 @@
 [css3-text-line-break-baspglwj-128.html]
   [white-space:pre-wrap]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:pre-line]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:break-spaces]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 
   [white-space:normal]
-    expected: FAIL
+    expected:
+      if os == "android": PASS
+      FAIL
 

testing/web-platform/meta/css/css-text/word-break/word-break-normal-bo-000.html.ini

@@ -2,4 +2,3 @@
   expected:
     if (os == "win") and (processor == "x86_64"): FAIL
     if (os == "win") and (processor == "aarch64"): FAIL
-    if os == "android": FAIL