Treat Unicode codepoints of category "Format" as non-spacing

Commit d8594d1 updated the list of non-spacing codepoints used
for calculating display width, but in doing so inadvertently removed
some, since the script used for that commit only considered combining
characters.

For complete coverage for zero-width characters, include codepoints in
the category Cf (Format). To reflect the wider purpose, also rename files
and update comments that referred specifically to combining characters.

Some of these ranges have been missing since v12, but due to lack of
field complaints it was determined not important enough to justify adding
special-case logic the backbranches.

Kyotaro Horiguchi

Report by Pavel Stehule
Discussion: https://www.postgresql.org/message-id/flat/CAFj8pRBE8yvpQ0FSkPCoe0Ny1jAAsAQ6j3qMgVwWvkqAoaaNmQ%40mail.gmail.com

Author: j-naylor

src/common/unicode/Makefile

@@ -18,7 +18,7 @@ LIBS += $(PTHREAD_LIBS)
 # By default, do nothing.
 all:
 
-update-unicode: unicode_norm_table.h unicode_combining_table.h unicode_east_asian_fw_table.h unicode_normprops_table.h unicode_norm_hashfunc.h
+update-unicode: unicode_norm_table.h unicode_nonspacing_table.h unicode_east_asian_fw_table.h unicode_normprops_table.h unicode_norm_hashfunc.h
 	mv $^ $(top_srcdir)/src/include/common/
 	$(MAKE) normalization-check
 
@@ -35,7 +35,7 @@ unicode_norm_hashfunc.h: unicode_norm_table.h
 unicode_norm_table.h: generate-unicode_norm_table.pl UnicodeData.txt CompositionExclusions.txt
 	$(PERL) $<
 
-unicode_combining_table.h: generate-unicode_combining_table.pl UnicodeData.txt
+unicode_nonspacing_table.h: generate-unicode_nonspacing_table.pl UnicodeData.txt
 	$(PERL) $^ >$@
 
 unicode_east_asian_fw_table.h: generate-unicode_east_asian_fw_table.pl EastAsianWidth.txt

src/common/unicode/generate-unicode_combining_table.pl renamed to src/common/unicode/generate-unicode_nonspacing_table.pl

@@ -15,27 +15,29 @@
 my $count = 0;
 
 print
-  "/* generated by src/common/unicode/generate-unicode_combining_table.pl, do not edit */\n\n";
+  "/* generated by src/common/unicode/generate-unicode_nonspacing_table.pl, do not edit */\n\n";
 
-print "static const struct mbinterval combining[] = {\n";
+print "static const struct mbinterval nonspacing[] = {\n";
 
 foreach my $line (<ARGV>)
 {
 	chomp $line;
 	my @fields = split ';', $line;
 	$codepoint = hex $fields[0];
 
-	if ($fields[2] eq 'Me' || $fields[2] eq 'Mn')
+	# Me and Mn refer to combining characters
+	# Cf refers to format characters
+	if ($fields[2] eq 'Me' || $fields[2] eq 'Mn' || $fields[2] eq 'Cf')
 	{
-		# combining character, save for start of range
+		# non-spacing character, save for start of range
 		if (!defined($range_start))
 		{
 			$range_start = $codepoint;
 		}
 	}
 	else
 	{
-		# not a combining character, print out previous range if any
+		# not a non-spacing character, print out previous range if any
 		if (defined($range_start))
 		{
 			printf "\t{0x%04X, 0x%04X},\n", $range_start, $prev_codepoint;

src/common/wchar.c

@@ -620,7 +620,7 @@ mbbisearch(pg_wchar ucs, const struct mbinterval *table, int max)
  *		value of -1.
  *
  *	  - Non-spacing and enclosing combining characters (general
- *		category code Mn or Me in the Unicode database) have a
+ *		category code Mn, Me or Cf in the Unicode database) have a
  *		column width of 0.
  *
  *	  - Spacing characters in the East Asian Wide (W) or East Asian
@@ -638,7 +638,7 @@ mbbisearch(pg_wchar ucs, const struct mbinterval *table, int max)
 static int
 ucs_wcwidth(pg_wchar ucs)
 {
-#include "common/unicode_combining_table.h"
+#include "common/unicode_nonspacing_table.h"
 #include "common/unicode_east_asian_fw_table.h"
 
 	/* test for 8-bit control characters */
@@ -657,8 +657,8 @@ ucs_wcwidth(pg_wchar ucs)
 	 * factor for display width leads to the correct behavior, so do that
 	 * search first.
 	 */
-	if (mbbisearch(ucs, combining,
-				   sizeof(combining) / sizeof(struct mbinterval) - 1))
+	if (mbbisearch(ucs, nonspacing,
+				   sizeof(nonspacing) / sizeof(struct mbinterval) - 1))
 		return 0;
 
 	/* binary search in table of wide characters */

src/include/common/unicode_combining_table.h renamed to src/include/common/unicode_nonspacing_table.h

@@ -1,20 +1,24 @@
-/* generated by src/common/unicode/generate-unicode_combining_table.pl, do not edit */
+/* generated by src/common/unicode/generate-unicode_nonspacing_table.pl, do not edit */
 
-static const struct mbinterval combining[] = {
+static const struct mbinterval nonspacing[] = {
+	{0x00AD, 0x00AD},
 	{0x0300, 0x036F},
 	{0x0483, 0x0489},
 	{0x0591, 0x05BD},
 	{0x05BF, 0x05BF},
 	{0x05C1, 0x05C2},
 	{0x05C4, 0x05C5},
 	{0x05C7, 0x05C7},
+	{0x0600, 0x0605},
 	{0x0610, 0x061A},
+	{0x061C, 0x061C},
 	{0x064B, 0x065F},
 	{0x0670, 0x0670},
-	{0x06D6, 0x06DC},
+	{0x06D6, 0x06DD},
 	{0x06DF, 0x06E4},
 	{0x06E7, 0x06E8},
 	{0x06EA, 0x06ED},
+	{0x070F, 0x070F},
 	{0x0711, 0x0711},
 	{0x0730, 0x074A},
 	{0x07A6, 0x07B0},
@@ -25,9 +29,8 @@ static const struct mbinterval combining[] = {
 	{0x0825, 0x0827},
 	{0x0829, 0x082D},
 	{0x0859, 0x085B},
-	{0x0898, 0x089F},
-	{0x08CA, 0x08E1},
-	{0x08E3, 0x0902},
+	{0x0890, 0x089F},
+	{0x08CA, 0x0902},
 	{0x093A, 0x093A},
 	{0x093C, 0x093C},
 	{0x0941, 0x0948},
@@ -114,8 +117,7 @@ static const struct mbinterval combining[] = {
 	{0x17C6, 0x17C6},
 	{0x17C9, 0x17D3},
 	{0x17DD, 0x17DD},
-	{0x180B, 0x180D},
-	{0x180F, 0x180F},
+	{0x180B, 0x180F},
 	{0x1885, 0x1886},
 	{0x18A9, 0x18A9},
 	{0x1920, 0x1922},
@@ -152,6 +154,9 @@ static const struct mbinterval combining[] = {
 	{0x1CF4, 0x1CF4},
 	{0x1CF8, 0x1CF9},
 	{0x1DC0, 0x1DFF},
+	{0x200B, 0x200F},
+	{0x202A, 0x202E},
+	{0x2060, 0x206F},
 	{0x20D0, 0x20F0},
 	{0x2CEF, 0x2CF1},
 	{0x2D7F, 0x2D7F},
@@ -196,6 +201,8 @@ static const struct mbinterval combining[] = {
 	{0xFB1E, 0xFB1E},
 	{0xFE00, 0xFE0F},
 	{0xFE20, 0xFE2F},
+	{0xFEFF, 0xFEFF},
+	{0xFFF9, 0xFFFB},
 	{0x101FD, 0x101FD},
 	{0x102E0, 0x102E0},
 	{0x10376, 0x1037A},
@@ -213,7 +220,8 @@ static const struct mbinterval combining[] = {
 	{0x1107F, 0x11081},
 	{0x110B3, 0x110B6},
 	{0x110B9, 0x110BA},
-	{0x110C2, 0x110C2},
+	{0x110BD, 0x110BD},
+	{0x110C2, 0x110CD},
 	{0x11100, 0x11102},
 	{0x11127, 0x1112B},
 	{0x1112D, 0x11134},
@@ -281,15 +289,16 @@ static const struct mbinterval combining[] = {
 	{0x11D95, 0x11D95},
 	{0x11D97, 0x11D97},
 	{0x11EF3, 0x11EF4},
+	{0x13430, 0x13438},
 	{0x16AF0, 0x16AF4},
 	{0x16B30, 0x16B36},
 	{0x16F4F, 0x16F4F},
 	{0x16F8F, 0x16F92},
 	{0x16FE4, 0x16FE4},
 	{0x1BC9D, 0x1BC9E},
-	{0x1CF00, 0x1CF46},
+	{0x1BCA0, 0x1CF46},
 	{0x1D167, 0x1D169},
-	{0x1D17B, 0x1D182},
+	{0x1D173, 0x1D182},
 	{0x1D185, 0x1D18B},
 	{0x1D1AA, 0x1D1AD},
 	{0x1D242, 0x1D244},
@@ -304,5 +313,5 @@ static const struct mbinterval combining[] = {
 	{0x1E2EC, 0x1E2EF},
 	{0x1E8D0, 0x1E8D6},
 	{0x1E944, 0x1E94A},
-	{0xE0100, 0xE01EF},
+	{0xE0001, 0xE01EF},
 };