Unicode normalization test broken output

[Peter Eisentraut]

I was playing with the Unicode normalization test in 
src/common/unicode/.  I think there is something wrong with how the test 
program reports failures.  For example, if I manually edit the 
norm_test_table.h to make a failure, like

-    { 74, { 0x00A8, 0 }, { 0x0020, 0x0308, 0 } },
+    { 74, { 0x00A8, 0 }, { 0x0020, 0x0309, 0 } },
then the output from the test is

FAILURE (NormalizationTest.txt line 74):
input:  00
expected:       0003
got     0003

which doesn't make sense.

There appear to be several off-by-more-than-one errors in norm_test.c 
print_wchar_str().  Attached is a patch to fix this (and make the output 
a bit prettier).  Result afterwards:

FAILURE (NormalizationTest.txt line 74):
input:    U+00A8
expected: U+0020 U+0309
got:      U+0020 U+0308

--
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
From b9dce0b6185ce8a05780d64a5a284b3eb7c7e7ea Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <pe...@eisentraut.org>
Date: Mon, 9 Dec 2019 12:02:49 +0100
Subject: [PATCH] Fix output of Unicode normalization test

Several off-by-more-than-one errors caused the output in case of a
test failure to be unintelligible.
---
 src/common/unicode/norm_test.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/common/unicode/norm_test.c b/src/common/unicode/norm_test.c
index fee58a184a..b6d34dd22c 100644
--- a/src/common/unicode/norm_test.c
+++ b/src/common/unicode/norm_test.c
@@ -23,17 +23,17 @@ static char *
 print_wchar_str(const pg_wchar *s)
 {
 #define BUF_DIGITS 50
-       static char buf[BUF_DIGITS * 2 + 1];
+       static char buf[BUF_DIGITS * 7 + 1];
        int                     i;
 
        i = 0;
        while (*s && i < BUF_DIGITS)
        {
-               snprintf(&buf[i * 2], 3, "%04X", *s);
+               sprintf(&buf[i * 7], "U+%04X ", *s);
                i++;
                s++;
        }
-       buf[i * 2] = '\0';
+       buf[i * 7] = '\0';
        return buf;
 }
 
@@ -67,9 +67,9 @@ main(int argc, char **argv)
                if (pg_wcscmp(test->output, result) != 0)
                {
                        printf("FAILURE (NormalizationTest.txt line %d):\n", 
test->linenum);
-                       printf("input:\t%s\n", print_wchar_str(test->input));
-                       printf("expected:\t%s\n", 
print_wchar_str(test->output));
-                       printf("got\t%s\n", print_wchar_str(result));
+                       printf("input:    %s\n", print_wchar_str(test->input));
+                       printf("expected: %s\n", print_wchar_str(test->output));
+                       printf("got:      %s\n", print_wchar_str(result));
                        printf("\n");
                        exit(1);
                }
-- 
2.24.0