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1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "minikin/GraphemeBreak.h"
18 
19 #include <vector>
20 
21 #include <gtest/gtest.h>
22 
23 #include "UnicodeUtils.h"
24 
25 namespace minikin {
26 
IsBreak(const char * src)27 bool IsBreak(const char* src) {
28     const size_t BUF_SIZE = 256;
29     uint16_t buf[BUF_SIZE];
30     size_t offset;
31     size_t size;
32     ParseUnicode(buf, BUF_SIZE, src, &size, &offset);
33     return GraphemeBreak::isGraphemeBreak(nullptr, buf, 0, size, offset);
34 }
35 
IsBreakWithAdvances(const float * advances,const char * src)36 bool IsBreakWithAdvances(const float* advances, const char* src) {
37     const size_t BUF_SIZE = 256;
38     uint16_t buf[BUF_SIZE];
39     size_t offset;
40     size_t size;
41     ParseUnicode(buf, BUF_SIZE, src, &size, &offset);
42     return GraphemeBreak::isGraphemeBreak(advances, buf, 0, size, offset);
43 }
44 
TEST(GraphemeBreak,utf16)45 TEST(GraphemeBreak, utf16) {
46     EXPECT_FALSE(IsBreak("U+D83C | U+DC31"));  // emoji, U+1F431
47 
48     // tests for invalid UTF-16
49     EXPECT_TRUE(IsBreak("U+D800 | U+D800"));  // two leading surrogates
50     EXPECT_TRUE(IsBreak("U+DC00 | U+DC00"));  // two trailing surrogates
51     EXPECT_TRUE(IsBreak("'a' | U+D800"));     // lonely leading surrogate
52     EXPECT_TRUE(IsBreak("U+DC00 | 'a'"));     // lonely trailing surrogate
53     EXPECT_TRUE(IsBreak("U+D800 | 'a'"));     // leading surrogate followed by non-surrogate
54     EXPECT_TRUE(IsBreak("'a' | U+DC00"));     // non-surrogate followed by trailing surrogate
55 }
56 
TEST(GraphemeBreak,rules)57 TEST(GraphemeBreak, rules) {
58     // Rule GB1, sot ÷; Rule GB2, ÷ eot
59     EXPECT_TRUE(IsBreak("| 'a'"));
60     EXPECT_TRUE(IsBreak("'a' |"));
61 
62     // Rule GB3, CR x LF
63     EXPECT_FALSE(IsBreak("U+000D | U+000A"));  // CR x LF
64 
65     // Rule GB4, (Control | CR | LF) ÷
66     EXPECT_TRUE(IsBreak("'a' | U+2028"));  // Line separator
67     EXPECT_TRUE(IsBreak("'a' | U+000D"));  // LF
68     EXPECT_TRUE(IsBreak("'a' | U+000A"));  // CR
69 
70     // Rule GB5, ÷ (Control | CR | LF)
71     EXPECT_TRUE(IsBreak("U+2028 | 'a'"));  // Line separator
72     EXPECT_TRUE(IsBreak("U+000D | 'a'"));  // LF
73     EXPECT_TRUE(IsBreak("U+000A | 'a'"));  // CR
74 
75     // Rule GB6, L x ( L | V | LV | LVT )
76     EXPECT_FALSE(IsBreak("U+1100 | U+1100"));  // L x L
77     EXPECT_FALSE(IsBreak("U+1100 | U+1161"));  // L x V
78     EXPECT_FALSE(IsBreak("U+1100 | U+AC00"));  // L x LV
79     EXPECT_FALSE(IsBreak("U+1100 | U+AC01"));  // L x LVT
80 
81     // Rule GB7, ( LV | V ) x ( V | T )
82     EXPECT_FALSE(IsBreak("U+AC00 | U+1161"));  // LV x V
83     EXPECT_FALSE(IsBreak("U+1161 | U+1161"));  // V x V
84     EXPECT_FALSE(IsBreak("U+AC00 | U+11A8"));  // LV x T
85     EXPECT_FALSE(IsBreak("U+1161 | U+11A8"));  // V x T
86 
87     // Rule GB8, ( LVT | T ) x T
88     EXPECT_FALSE(IsBreak("U+AC01 | U+11A8"));  // LVT x T
89     EXPECT_FALSE(IsBreak("U+11A8 | U+11A8"));  // T x T
90 
91     // Other hangul pairs not counted above _are_ breaks (GB10)
92     EXPECT_TRUE(IsBreak("U+AC00 | U+1100"));  // LV x L
93     EXPECT_TRUE(IsBreak("U+AC01 | U+1100"));  // LVT x L
94     EXPECT_TRUE(IsBreak("U+11A8 | U+1100"));  // T x L
95     EXPECT_TRUE(IsBreak("U+11A8 | U+AC00"));  // T x LV
96     EXPECT_TRUE(IsBreak("U+11A8 | U+AC01"));  // T x LVT
97 
98     // Rule GB12 and Rule GB13, Regional_Indicator x Regional_Indicator
99     EXPECT_FALSE(IsBreak("U+1F1FA | U+1F1F8"));
100     EXPECT_TRUE(IsBreak("U+1F1FA U+1F1F8 | U+1F1FA U+1F1F8"));   // Regional indicator pair (flag)
101     EXPECT_FALSE(IsBreak("U+1F1FA | U+1F1F8 U+1F1FA U+1F1F8"));  // Regional indicator pair (flag)
102     EXPECT_FALSE(IsBreak("U+1F1FA U+1F1F8 U+1F1FA | U+1F1F8"));  // Regional indicator pair (flag)
103 
104     EXPECT_TRUE(IsBreak("U+1F1FA U+1F1F8 | U+1F1FA"));   // Regional indicator pair (flag)
105     EXPECT_FALSE(IsBreak("U+1F1FA | U+1F1F8 U+1F1FA"));  // Regional indicator pair (flag)
106     // Same case as the two above, knowing that the first two characters ligate, which is what
107     // would typically happen.
108     const float firstPairLigated[] = {1.0, 0.0, 0.0, 0.0, 1.0, 0.0};  // Two entries per codepoint
109     EXPECT_TRUE(IsBreakWithAdvances(firstPairLigated, "U+1F1FA U+1F1F8 | U+1F1FA"));
110     EXPECT_FALSE(IsBreakWithAdvances(firstPairLigated, "U+1F1FA | U+1F1F8 U+1F1FA"));
111     // Repeat the tests, But now the font doesn't have a ligature for the first two characters,
112     // while it does have a ligature for the last two. This could happen for fonts that do not
113     // support some (potentially encoded later than they were developed) flags.
114     const float secondPairLigated[] = {1.0, 0.0, 1.0, 0.0, 0.0, 0.0};
115     EXPECT_FALSE(IsBreakWithAdvances(secondPairLigated, "U+1F1FA U+1F1F8 | U+1F1FA"));
116     EXPECT_TRUE(IsBreakWithAdvances(secondPairLigated, "U+1F1FA | U+1F1F8 U+1F1FA"));
117 
118     EXPECT_TRUE(IsBreak("'a' U+1F1FA U+1F1F8 | U+1F1FA"));   // Regional indicator pair (flag)
119     EXPECT_FALSE(IsBreak("'a' U+1F1FA | U+1F1F8 U+1F1FA"));  // Regional indicator pair (flag)
120 
121     EXPECT_TRUE(
122             IsBreak("'a' U+1F1FA U+1F1F8 | U+1F1FA U+1F1F8"));  // Regional indicator pair (flag)
123     EXPECT_FALSE(
124             IsBreak("'a' U+1F1FA | U+1F1F8 U+1F1FA U+1F1F8"));  // Regional indicator pair (flag)
125     EXPECT_FALSE(
126             IsBreak("'a' U+1F1FA U+1F1F8 U+1F1FA | U+1F1F8"));  // Regional indicator pair (flag)
127 
128     // Rule GB9, x (Extend | ZWJ)
129     EXPECT_FALSE(IsBreak("'a' | U+0301"));  // combining accent
130     EXPECT_FALSE(IsBreak("'a' | U+200D"));  // ZWJ
131     // Rule GB9a, x SpacingMark
132     EXPECT_FALSE(IsBreak("U+0915 | U+093E"));  // KA, AA (spacing mark)
133     // Rule GB9b, Prepend x
134     // see tailoring test for prepend, as current ICU doesn't have any characters in the class
135 
136     // Rule GB999, Any ÷ Any
137     EXPECT_TRUE(IsBreak("'a' | 'b'"));
138     EXPECT_TRUE(IsBreak("'f' | 'i'"));              // probable ligature
139     EXPECT_TRUE(IsBreak("U+0644 | U+0627"));        // probable ligature, lam + alef
140     EXPECT_TRUE(IsBreak("U+4E00 | U+4E00"));        // CJK ideographs
141     EXPECT_TRUE(IsBreak("'a' | U+1F1FA U+1F1F8"));  // Regional indicator pair (flag)
142     EXPECT_TRUE(IsBreak("U+1F1FA U+1F1F8 | 'a'"));  // Regional indicator pair (flag)
143 
144     // Extended rule for emoji tag sequence.
145     EXPECT_TRUE(IsBreak("'a' | U+1F3F4 'a'"));
146     EXPECT_TRUE(IsBreak("'a' U+1F3F4 | 'a'"));
147 
148     // Immediate tag_term after tag_base.
149     EXPECT_TRUE(IsBreak("'a' | U+1F3F4 U+E007F 'a'"));
150     EXPECT_FALSE(IsBreak("U+1F3F4 | U+E007F"));
151     EXPECT_TRUE(IsBreak("'a' U+1F3F4 U+E007F | 'a'"));
152 
153     // Flag sequence
154     // U+1F3F4 U+E0067 U+E0062 U+E0073 U+E0063 U+E0074 U+E007F is emoji tag sequence for the flag
155     // of Scotland.
156     // U+1F3F4 is WAVING BLACK FLAG. This can be a tag_base character.
157     // U+E0067 is TAG LATIN SMALL LETTER G. This can be a part of tag_spec.
158     // U+E0062 is TAG LATIN SMALL LETTER B. This can be a part of tag_spec.
159     // U+E0073 is TAG LATIN SMALL LETTER S. This can be a part of tag_spec.
160     // U+E0063 is TAG LATIN SMALL LETTER C. This can be a part of tag_spec.
161     // U+E0074 is TAG LATIN SMALL LETTER T. This can be a part of tag_spec.
162     // U+E007F is CANCEL TAG. This is a tag_term character.
163     EXPECT_TRUE(IsBreak("'a' | U+1F3F4 U+E0067 U+E0062 U+E0073 U+E0063 U+E0074 U+E007F"));
164     EXPECT_FALSE(IsBreak("U+1F3F4 | U+E0067 U+E0062 U+E0073 U+E0063 U+E0074 U+E007F"));
165     EXPECT_FALSE(IsBreak("U+1F3F4 U+E0067 | U+E0062 U+E0073 U+E0063 U+E0074 U+E007F"));
166     EXPECT_FALSE(IsBreak("U+1F3F4 U+E0067 U+E0062 | U+E0073 U+E0063 U+E0074 U+E007F"));
167     EXPECT_FALSE(IsBreak("U+1F3F4 U+E0067 U+E0062 U+E0073 | U+E0063 U+E0074 U+E007F"));
168     EXPECT_FALSE(IsBreak("U+1F3F4 U+E0067 U+E0062 U+E0073 U+E0063 | U+E0074 U+E007F"));
169     EXPECT_FALSE(IsBreak("U+1F3F4 U+E0067 U+E0062 U+E0073 U+E0063 U+E0074 | U+E007F"));
170     EXPECT_TRUE(IsBreak("U+1F3F4 U+E0067 U+E0062 U+E0073 U+E0063 U+E0074 U+E007F | 'a'"));
171 }
172 
TEST(GraphemeBreak,tailoring)173 TEST(GraphemeBreak, tailoring) {
174     // control characters that we interpret as "extend"
175     EXPECT_FALSE(IsBreak("'a' | U+00AD"));   // soft hyphen
176     EXPECT_FALSE(IsBreak("'a' | U+200B"));   // zwsp
177     EXPECT_FALSE(IsBreak("'a' | U+200E"));   // lrm
178     EXPECT_FALSE(IsBreak("'a' | U+202A"));   // lre
179     EXPECT_FALSE(IsBreak("'a' | U+E0041"));  // tag character
180 
181     // UTC-approved characters for the Prepend class
182     EXPECT_FALSE(IsBreak("U+06DD | U+0661"));  // arabic subtending mark + digit one
183 
184     EXPECT_TRUE(IsBreak("U+0E01 | U+0E33"));  // Thai sara am
185 
186     // virama is not a grapheme break, but "pure killer" is
187     EXPECT_FALSE(IsBreak("U+0915 | U+094D U+0915"));  // Devanagari ka+virama+ka
188     EXPECT_FALSE(IsBreak("U+0915 U+094D | U+0915"));  // Devanagari ka+virama+ka
189     EXPECT_FALSE(IsBreak("U+0E01 | U+0E3A U+0E01"));  // thai phinthu = pure killer
190     EXPECT_TRUE(IsBreak("U+0E01 U+0E3A | U+0E01"));   // thai phinthu = pure killer
191 
192     // Repetition of above tests, but with a given advances array that implies everything
193     // became just one cluster.
194     const float conjoined[] = {1.0, 0.0, 0.0};
195     EXPECT_FALSE(IsBreakWithAdvances(conjoined,
196                                      "U+0915 | U+094D U+0915"));  // Devanagari ka+virama+ka
197     EXPECT_FALSE(IsBreakWithAdvances(conjoined,
198                                      "U+0915 U+094D | U+0915"));  // Devanagari ka+virama+ka
199     EXPECT_FALSE(IsBreakWithAdvances(conjoined,
200                                      "U+0E01 | U+0E3A U+0E01"));  // thai phinthu = pure killer
201     EXPECT_TRUE(IsBreakWithAdvances(conjoined,
202                                     "U+0E01 U+0E3A | U+0E01"));  // thai phinthu = pure killer
203 
204     // Repetition of above tests, but with a given advances array that the virama did not
205     // form a cluster with the following consonant. The difference is that there is now
206     // a grapheme break after the virama in ka+virama+ka.
207     const float separate[] = {1.0, 0.0, 1.0};
208     EXPECT_FALSE(IsBreakWithAdvances(separate,
209                                      "U+0915 | U+094D U+0915"));  // Devanagari ka+virama+ka
210     EXPECT_TRUE(IsBreakWithAdvances(separate,
211                                     "U+0915 U+094D | U+0915"));  // Devanagari ka+virama+ka
212     EXPECT_FALSE(IsBreakWithAdvances(separate,
213                                      "U+0E01 | U+0E3A U+0E01"));  // thai phinthu = pure killer
214     EXPECT_TRUE(IsBreakWithAdvances(separate,
215                                     "U+0E01 U+0E3A | U+0E01"));  // thai phinthu = pure killer
216 
217     // suppress grapheme breaks in zwj emoji sequences
218     EXPECT_FALSE(IsBreak("U+1F469 U+200D | U+2764 U+FE0F U+200D U+1F48B U+200D U+1F468"));
219     EXPECT_FALSE(IsBreak("U+1F469 U+200D U+2764 U+FE0F U+200D | U+1F48B U+200D U+1F468"));
220     EXPECT_FALSE(IsBreak("U+1F469 U+200D U+2764 U+FE0F U+200D U+1F48B U+200D | U+1F468"));
221     EXPECT_FALSE(IsBreak("U+1F468 U+200D | U+1F469 U+200D U+1F466"));
222     EXPECT_FALSE(IsBreak("U+1F468 U+200D U+1F469 U+200D | U+1F466"));
223     EXPECT_FALSE(IsBreak("U+1F469 U+200D | U+1F469 U+200D U+1F467 U+200D U+1F466"));
224     EXPECT_FALSE(IsBreak("U+1F469 U+200D U+1F469 U+200D | U+1F467 U+200D U+1F466"));
225     EXPECT_FALSE(IsBreak("U+1F469 U+200D U+1F469 U+200D U+1F467 U+200D | U+1F466"));
226     EXPECT_FALSE(IsBreak("U+1F441 U+200D | U+1F5E8"));
227 
228     // Do not break before and after zwj with all kind of emoji characters.
229     EXPECT_FALSE(IsBreak("U+1F431 | U+200D U+1F464"));
230     EXPECT_FALSE(IsBreak("U+1F431 U+200D | U+1F464"));
231 
232     // ARABIC LETTER BEH + ZWJ + heart, not a zwj emoji sequence, so we preserve the break
233     EXPECT_TRUE(IsBreak("U+0628 U+200D | U+2764"));
234 }
235 
TEST(GraphemeBreak,emojiModifiers)236 TEST(GraphemeBreak, emojiModifiers) {
237     EXPECT_FALSE(IsBreak("U+261D | U+1F3FB"));   // white up pointing index + modifier
238     EXPECT_FALSE(IsBreak("U+270C | U+1F3FB"));   // victory hand + modifier
239     EXPECT_FALSE(IsBreak("U+1F466 | U+1F3FB"));  // boy + modifier
240     EXPECT_FALSE(IsBreak("U+1F466 | U+1F3FC"));  // boy + modifier
241     EXPECT_FALSE(IsBreak("U+1F466 | U+1F3FD"));  // boy + modifier
242     EXPECT_FALSE(IsBreak("U+1F466 | U+1F3FE"));  // boy + modifier
243     EXPECT_FALSE(IsBreak("U+1F466 | U+1F3FF"));  // boy + modifier
244     EXPECT_FALSE(IsBreak("U+1F918 | U+1F3FF"));  // sign of the horns + modifier
245     EXPECT_FALSE(IsBreak("U+1F933 | U+1F3FF"));  // selfie (Unicode 9) + modifier
246     // Reptition of the tests above, with the knowledge that they are ligated.
247     const float ligated1_2[] = {1.0, 0.0, 0.0};
248     const float ligated2_2[] = {1.0, 0.0, 0.0, 0.0};
249     EXPECT_FALSE(IsBreakWithAdvances(ligated1_2, "U+261D | U+1F3FB"));
250     EXPECT_FALSE(IsBreakWithAdvances(ligated1_2, "U+270C | U+1F3FB"));
251     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F466 | U+1F3FB"));
252     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F466 | U+1F3FC"));
253     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F466 | U+1F3FD"));
254     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F466 | U+1F3FE"));
255     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F466 | U+1F3FF"));
256     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F918 | U+1F3FF"));
257     EXPECT_FALSE(IsBreakWithAdvances(ligated2_2, "U+1F933 | U+1F3FF"));
258     // Reptition of the tests above, with the knowledge that they are not ligated.
259     const float unligated1_2[] = {1.0, 1.0, 0.0};
260     const float unligated2_2[] = {1.0, 0.0, 1.0, 0.0};
261     EXPECT_TRUE(IsBreakWithAdvances(unligated1_2, "U+261D | U+1F3FB"));
262     EXPECT_TRUE(IsBreakWithAdvances(unligated1_2, "U+270C | U+1F3FB"));
263     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F466 | U+1F3FB"));
264     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F466 | U+1F3FC"));
265     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F466 | U+1F3FD"));
266     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F466 | U+1F3FE"));
267     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F466 | U+1F3FF"));
268     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F918 | U+1F3FF"));
269     EXPECT_TRUE(IsBreakWithAdvances(unligated2_2, "U+1F933 | U+1F3FF"));
270 
271     // adding extend characters between emoji base and modifier doesn't affect grapheme cluster
272     EXPECT_FALSE(IsBreak("U+270C U+FE0E | U+1F3FB"));  // victory hand + text style + modifier
273     EXPECT_FALSE(IsBreak("U+270C U+FE0F | U+1F3FB"));  // heart + emoji style + modifier
274     // Reptition of the two tests above, with the knowledge that they are ligated.
275     const float ligated1_1_2[] = {1.0, 0.0, 0.0, 0.0};
276     EXPECT_FALSE(IsBreakWithAdvances(ligated1_1_2, "U+270C U+FE0E | U+1F3FB"));
277     EXPECT_FALSE(IsBreakWithAdvances(ligated1_1_2, "U+270C U+FE0F | U+1F3FB"));
278     // Reptition of the first two tests, with the knowledge that they are not ligated.
279     const float unligated1_1_2[] = {1.0, 0.0, 1.0, 0.0};
280     EXPECT_TRUE(IsBreakWithAdvances(unligated1_1_2, "U+270C U+FE0E | U+1F3FB"));
281     EXPECT_TRUE(IsBreakWithAdvances(unligated1_1_2, "U+270C U+FE0F | U+1F3FB"));
282 
283     // rat is not an emoji modifer
284     EXPECT_TRUE(IsBreak("U+1F466 | U+1F400"));  // boy + rat
285 }
286 
TEST(GraphemeBreak,genderBalancedEmoji)287 TEST(GraphemeBreak, genderBalancedEmoji) {
288     // U+1F469 is WOMAN, U+200D is ZWJ, U+1F4BC is BRIEFCASE.
289     EXPECT_FALSE(IsBreak("U+1F469 | U+200D U+1F4BC"));
290     EXPECT_FALSE(IsBreak("U+1F469 U+200D | U+1F4BC"));
291     // The above two cases, when the ligature is not supported in the font. We now expect a break
292     // between them.
293     const float unligated2_1_2[] = {1.0, 0.0, 0.0, 1.0, 0.0};
294     EXPECT_FALSE(IsBreakWithAdvances(unligated2_1_2, "U+1F469 | U+200D U+1F4BC"));
295     EXPECT_TRUE(IsBreakWithAdvances(unligated2_1_2, "U+1F469 U+200D | U+1F4BC"));
296 
297     // U+2695 has now emoji property, so should be part of ZWJ sequence.
298     EXPECT_FALSE(IsBreak("U+1F469 | U+200D U+2695"));
299     EXPECT_FALSE(IsBreak("U+1F469 U+200D | U+2695"));
300     // The above two cases, when the ligature is not supported in the font. We now expect a break
301     // between them.
302     const float unligated2_1_1[] = {1.0, 0.0, 0.0, 1.0};
303     EXPECT_FALSE(IsBreakWithAdvances(unligated2_1_1, "U+1F469 | U+200D U+2695"));
304     EXPECT_TRUE(IsBreakWithAdvances(unligated2_1_1, "U+1F469 U+200D | U+2695"));
305 }
306 
TEST(GraphemeBreak,offsets)307 TEST(GraphemeBreak, offsets) {
308     uint16_t string[] = {0x0041, 0x06DD, 0x0045, 0x0301, 0x0049, 0x0301};
309     EXPECT_TRUE(GraphemeBreak::isGraphemeBreak(nullptr, string, 2, 3, 2));
310     EXPECT_FALSE(GraphemeBreak::isGraphemeBreak(nullptr, string, 2, 3, 3));
311     EXPECT_TRUE(GraphemeBreak::isGraphemeBreak(nullptr, string, 2, 3, 4));
312     EXPECT_TRUE(GraphemeBreak::isGraphemeBreak(nullptr, string, 2, 3, 5));
313 }
314 
TEST(GraphemeBreak,startWithZWJ)315 TEST(GraphemeBreak, startWithZWJ) {
316     // It used to be looking before the ZWJ char even if it is the start of the text.
317     IsBreak("U+200D | U+1F5E8");  // UB sanitizer will catch if minikin looks the char before ZWJ
318 }
319 
320 }  // namespace minikin
321