git/t/helper/test-json-writer.c
Jeff Hostetler 75459410ed json_writer: new routines to create JSON data
Add "struct json_writer" and a series of jw_ routines to compose JSON
data into a string buffer.  The resulting string may then be printed by
commands wanting to support a JSON-like output format.

The json_writer is limited to correctly formatting structured data for
output.  It does not attempt to build an object model of the JSON data.

We say "JSON-like" because we do not enforce the Unicode (usually UTF-8)
requirement on string fields.  Internally, Git does not necessarily have
Unicode/UTF-8 data for most fields, so it is currently unclear the best
way to enforce that requirement.  For example, on Linux pathnames can
contain arbitrary 8-bit character data, so a command like "status" would
not know how to encode the reported pathnames.  We may want to revisit
this (or double encode such strings) in the future.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: René Scharfe <l.s.r@web.de>
Helped-by: Wink Saville <wink@saville.com>
Helped-by: Ramsay Jones <ramsay@ramsayjones.plus.com>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-07-16 13:55:39 -07:00

565 lines
12 KiB
C

#include "test-tool.h"
#include "cache.h"
#include "json-writer.h"
static const char *expect_obj1 = "{\"a\":\"abc\",\"b\":42,\"c\":true}";
static const char *expect_obj2 = "{\"a\":-1,\"b\":2147483647,\"c\":0}";
static const char *expect_obj3 = "{\"a\":0,\"b\":4294967295,\"c\":9223372036854775807}";
static const char *expect_obj4 = "{\"t\":true,\"f\":false,\"n\":null}";
static const char *expect_obj5 = "{\"abc\\tdef\":\"abc\\\\def\"}";
static const char *expect_obj6 = "{\"a\":3.14}";
static const char *pretty_obj1 = ("{\n"
" \"a\": \"abc\",\n"
" \"b\": 42,\n"
" \"c\": true\n"
"}");
static const char *pretty_obj2 = ("{\n"
" \"a\": -1,\n"
" \"b\": 2147483647,\n"
" \"c\": 0\n"
"}");
static const char *pretty_obj3 = ("{\n"
" \"a\": 0,\n"
" \"b\": 4294967295,\n"
" \"c\": 9223372036854775807\n"
"}");
static const char *pretty_obj4 = ("{\n"
" \"t\": true,\n"
" \"f\": false,\n"
" \"n\": null\n"
"}");
static struct json_writer obj1 = JSON_WRITER_INIT;
static struct json_writer obj2 = JSON_WRITER_INIT;
static struct json_writer obj3 = JSON_WRITER_INIT;
static struct json_writer obj4 = JSON_WRITER_INIT;
static struct json_writer obj5 = JSON_WRITER_INIT;
static struct json_writer obj6 = JSON_WRITER_INIT;
static void make_obj1(int pretty)
{
jw_object_begin(&obj1, pretty);
{
jw_object_string(&obj1, "a", "abc");
jw_object_intmax(&obj1, "b", 42);
jw_object_true(&obj1, "c");
}
jw_end(&obj1);
}
static void make_obj2(int pretty)
{
jw_object_begin(&obj2, pretty);
{
jw_object_intmax(&obj2, "a", -1);
jw_object_intmax(&obj2, "b", 0x7fffffff);
jw_object_intmax(&obj2, "c", 0);
}
jw_end(&obj2);
}
static void make_obj3(int pretty)
{
jw_object_begin(&obj3, pretty);
{
jw_object_intmax(&obj3, "a", 0);
jw_object_intmax(&obj3, "b", 0xffffffff);
jw_object_intmax(&obj3, "c", 0x7fffffffffffffffULL);
}
jw_end(&obj3);
}
static void make_obj4(int pretty)
{
jw_object_begin(&obj4, pretty);
{
jw_object_true(&obj4, "t");
jw_object_false(&obj4, "f");
jw_object_null(&obj4, "n");
}
jw_end(&obj4);
}
static void make_obj5(int pretty)
{
jw_object_begin(&obj5, pretty);
{
jw_object_string(&obj5, "abc" "\x09" "def", "abc" "\\" "def");
}
jw_end(&obj5);
}
static void make_obj6(int pretty)
{
jw_object_begin(&obj6, pretty);
{
jw_object_double(&obj6, "a", 2, 3.14159);
}
jw_end(&obj6);
}
static const char *expect_arr1 = "[\"abc\",42,true]";
static const char *expect_arr2 = "[-1,2147483647,0]";
static const char *expect_arr3 = "[0,4294967295,9223372036854775807]";
static const char *expect_arr4 = "[true,false,null]";
static const char *pretty_arr1 = ("[\n"
" \"abc\",\n"
" 42,\n"
" true\n"
"]");
static const char *pretty_arr2 = ("[\n"
" -1,\n"
" 2147483647,\n"
" 0\n"
"]");
static const char *pretty_arr3 = ("[\n"
" 0,\n"
" 4294967295,\n"
" 9223372036854775807\n"
"]");
static const char *pretty_arr4 = ("[\n"
" true,\n"
" false,\n"
" null\n"
"]");
static struct json_writer arr1 = JSON_WRITER_INIT;
static struct json_writer arr2 = JSON_WRITER_INIT;
static struct json_writer arr3 = JSON_WRITER_INIT;
static struct json_writer arr4 = JSON_WRITER_INIT;
static void make_arr1(int pretty)
{
jw_array_begin(&arr1, pretty);
{
jw_array_string(&arr1, "abc");
jw_array_intmax(&arr1, 42);
jw_array_true(&arr1);
}
jw_end(&arr1);
}
static void make_arr2(int pretty)
{
jw_array_begin(&arr2, pretty);
{
jw_array_intmax(&arr2, -1);
jw_array_intmax(&arr2, 0x7fffffff);
jw_array_intmax(&arr2, 0);
}
jw_end(&arr2);
}
static void make_arr3(int pretty)
{
jw_array_begin(&arr3, pretty);
{
jw_array_intmax(&arr3, 0);
jw_array_intmax(&arr3, 0xffffffff);
jw_array_intmax(&arr3, 0x7fffffffffffffffULL);
}
jw_end(&arr3);
}
static void make_arr4(int pretty)
{
jw_array_begin(&arr4, pretty);
{
jw_array_true(&arr4);
jw_array_false(&arr4);
jw_array_null(&arr4);
}
jw_end(&arr4);
}
static char *expect_nest1 =
"{\"obj1\":{\"a\":\"abc\",\"b\":42,\"c\":true},\"arr1\":[\"abc\",42,true]}";
static struct json_writer nest1 = JSON_WRITER_INIT;
static void make_nest1(int pretty)
{
jw_object_begin(&nest1, pretty);
{
jw_object_sub_jw(&nest1, "obj1", &obj1);
jw_object_sub_jw(&nest1, "arr1", &arr1);
}
jw_end(&nest1);
}
static char *expect_inline1 =
"{\"obj1\":{\"a\":\"abc\",\"b\":42,\"c\":true},\"arr1\":[\"abc\",42,true]}";
static char *pretty_inline1 =
("{\n"
" \"obj1\": {\n"
" \"a\": \"abc\",\n"
" \"b\": 42,\n"
" \"c\": true\n"
" },\n"
" \"arr1\": [\n"
" \"abc\",\n"
" 42,\n"
" true\n"
" ]\n"
"}");
static struct json_writer inline1 = JSON_WRITER_INIT;
static void make_inline1(int pretty)
{
jw_object_begin(&inline1, pretty);
{
jw_object_inline_begin_object(&inline1, "obj1");
{
jw_object_string(&inline1, "a", "abc");
jw_object_intmax(&inline1, "b", 42);
jw_object_true(&inline1, "c");
}
jw_end(&inline1);
jw_object_inline_begin_array(&inline1, "arr1");
{
jw_array_string(&inline1, "abc");
jw_array_intmax(&inline1, 42);
jw_array_true(&inline1);
}
jw_end(&inline1);
}
jw_end(&inline1);
}
static char *expect_inline2 =
"[[1,2],[3,4],{\"a\":\"abc\"}]";
static char *pretty_inline2 =
("[\n"
" [\n"
" 1,\n"
" 2\n"
" ],\n"
" [\n"
" 3,\n"
" 4\n"
" ],\n"
" {\n"
" \"a\": \"abc\"\n"
" }\n"
"]");
static struct json_writer inline2 = JSON_WRITER_INIT;
static void make_inline2(int pretty)
{
jw_array_begin(&inline2, pretty);
{
jw_array_inline_begin_array(&inline2);
{
jw_array_intmax(&inline2, 1);
jw_array_intmax(&inline2, 2);
}
jw_end(&inline2);
jw_array_inline_begin_array(&inline2);
{
jw_array_intmax(&inline2, 3);
jw_array_intmax(&inline2, 4);
}
jw_end(&inline2);
jw_array_inline_begin_object(&inline2);
{
jw_object_string(&inline2, "a", "abc");
}
jw_end(&inline2);
}
jw_end(&inline2);
}
/*
* When super is compact, we expect subs to be compacted (even if originally
* pretty).
*/
static const char *expect_mixed1 =
("{\"obj1\":{\"a\":\"abc\",\"b\":42,\"c\":true},"
"\"arr1\":[\"abc\",42,true]}");
/*
* When super is pretty, a compact sub (obj1) is kept compact and a pretty
* sub (arr1) is re-indented.
*/
static const char *pretty_mixed1 =
("{\n"
" \"obj1\": {\"a\":\"abc\",\"b\":42,\"c\":true},\n"
" \"arr1\": [\n"
" \"abc\",\n"
" 42,\n"
" true\n"
" ]\n"
"}");
static struct json_writer mixed1 = JSON_WRITER_INIT;
static void make_mixed1(int pretty)
{
jw_init(&obj1);
jw_init(&arr1);
make_obj1(0); /* obj1 is compact */
make_arr1(1); /* arr1 is pretty */
jw_object_begin(&mixed1, pretty);
{
jw_object_sub_jw(&mixed1, "obj1", &obj1);
jw_object_sub_jw(&mixed1, "arr1", &arr1);
}
jw_end(&mixed1);
}
static void cmp(const char *test, const struct json_writer *jw, const char *exp)
{
if (!strcmp(jw->json.buf, exp))
return;
printf("error[%s]: observed '%s' expected '%s'\n",
test, jw->json.buf, exp);
exit(1);
}
#define t(v) do { make_##v(0); cmp(#v, &v, expect_##v); } while (0)
#define p(v) do { make_##v(1); cmp(#v, &v, pretty_##v); } while (0)
/*
* Run some basic regression tests with some known patterns.
* These tests also demonstrate how to use the jw_ API.
*/
static int unit_tests(void)
{
/* comptact (canonical) forms */
t(obj1);
t(obj2);
t(obj3);
t(obj4);
t(obj5);
t(obj6);
t(arr1);
t(arr2);
t(arr3);
t(arr4);
t(nest1);
t(inline1);
t(inline2);
jw_init(&obj1);
jw_init(&obj2);
jw_init(&obj3);
jw_init(&obj4);
jw_init(&arr1);
jw_init(&arr2);
jw_init(&arr3);
jw_init(&arr4);
jw_init(&inline1);
jw_init(&inline2);
/* pretty forms */
p(obj1);
p(obj2);
p(obj3);
p(obj4);
p(arr1);
p(arr2);
p(arr3);
p(arr4);
p(inline1);
p(inline2);
/* mixed forms */
t(mixed1);
jw_init(&mixed1);
p(mixed1);
return 0;
}
static void get_s(int line_nr, char **s_in)
{
*s_in = strtok(NULL, " ");
if (!*s_in)
die("line[%d]: expected: <s>", line_nr);
}
static void get_i(int line_nr, intmax_t *s_in)
{
char *s;
char *endptr;
get_s(line_nr, &s);
*s_in = strtol(s, &endptr, 10);
if (*endptr || errno == ERANGE)
die("line[%d]: invalid integer value", line_nr);
}
static void get_d(int line_nr, double *s_in)
{
char *s;
char *endptr;
get_s(line_nr, &s);
*s_in = strtod(s, &endptr);
if (*endptr || errno == ERANGE)
die("line[%d]: invalid float value", line_nr);
}
static int pretty;
#define MAX_LINE_LENGTH (64 * 1024)
static char *get_trimmed_line(char *buf, int buf_size)
{
int len;
if (!fgets(buf, buf_size, stdin))
return NULL;
len = strlen(buf);
while (len > 0) {
char c = buf[len - 1];
if (c == '\n' || c == '\r' || c == ' ' || c == '\t')
buf[--len] = 0;
else
break;
}
while (*buf == ' ' || *buf == '\t')
buf++;
return buf;
}
static int scripted(void)
{
struct json_writer jw = JSON_WRITER_INIT;
char buf[MAX_LINE_LENGTH];
char *line;
int line_nr = 0;
line = get_trimmed_line(buf, MAX_LINE_LENGTH);
if (!line)
return 0;
if (!strcmp(line, "object"))
jw_object_begin(&jw, pretty);
else if (!strcmp(line, "array"))
jw_array_begin(&jw, pretty);
else
die("expected first line to be 'object' or 'array'");
while ((line = get_trimmed_line(buf, MAX_LINE_LENGTH)) != NULL) {
char *verb;
char *key;
char *s_value;
intmax_t i_value;
double d_value;
line_nr++;
verb = strtok(line, " ");
if (!strcmp(verb, "end")) {
jw_end(&jw);
}
else if (!strcmp(verb, "object-string")) {
get_s(line_nr, &key);
get_s(line_nr, &s_value);
jw_object_string(&jw, key, s_value);
}
else if (!strcmp(verb, "object-int")) {
get_s(line_nr, &key);
get_i(line_nr, &i_value);
jw_object_intmax(&jw, key, i_value);
}
else if (!strcmp(verb, "object-double")) {
get_s(line_nr, &key);
get_i(line_nr, &i_value);
get_d(line_nr, &d_value);
jw_object_double(&jw, key, i_value, d_value);
}
else if (!strcmp(verb, "object-true")) {
get_s(line_nr, &key);
jw_object_true(&jw, key);
}
else if (!strcmp(verb, "object-false")) {
get_s(line_nr, &key);
jw_object_false(&jw, key);
}
else if (!strcmp(verb, "object-null")) {
get_s(line_nr, &key);
jw_object_null(&jw, key);
}
else if (!strcmp(verb, "object-object")) {
get_s(line_nr, &key);
jw_object_inline_begin_object(&jw, key);
}
else if (!strcmp(verb, "object-array")) {
get_s(line_nr, &key);
jw_object_inline_begin_array(&jw, key);
}
else if (!strcmp(verb, "array-string")) {
get_s(line_nr, &s_value);
jw_array_string(&jw, s_value);
}
else if (!strcmp(verb, "array-int")) {
get_i(line_nr, &i_value);
jw_array_intmax(&jw, i_value);
}
else if (!strcmp(verb, "array-double")) {
get_i(line_nr, &i_value);
get_d(line_nr, &d_value);
jw_array_double(&jw, i_value, d_value);
}
else if (!strcmp(verb, "array-true"))
jw_array_true(&jw);
else if (!strcmp(verb, "array-false"))
jw_array_false(&jw);
else if (!strcmp(verb, "array-null"))
jw_array_null(&jw);
else if (!strcmp(verb, "array-object"))
jw_array_inline_begin_object(&jw);
else if (!strcmp(verb, "array-array"))
jw_array_inline_begin_array(&jw);
else
die("unrecognized token: '%s'", verb);
}
if (!jw_is_terminated(&jw))
die("json not terminated: '%s'", jw.json.buf);
printf("%s\n", jw.json.buf);
strbuf_release(&jw.json);
return 0;
}
int cmd__json_writer(int argc, const char **argv)
{
argc--; /* skip over "json-writer" arg */
argv++;
if (argc > 0 && argv[0][0] == '-') {
if (!strcmp(argv[0], "-u") || !strcmp(argv[0], "--unit"))
return unit_tests();
if (!strcmp(argv[0], "-p") || !strcmp(argv[0], "--pretty"))
pretty = 1;
}
return scripted();
}